Yorkshire Water Engineering Specification
Section 03.02 CESWI
Yorkshire Water Services
Civil
CESWI
03.02
Technical Author
Chris Branigan
Engineering Specification v22
Y2203 AIN MFN ENG SP Z 0302 AP.A01
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Yorkshire Water Engineering Specification
Section 03.02 CESWI
CIVIL ENGINEERING SPECIFICATION FOR THE WATER INDUSTRY
(SEVENTH EDITION)
MARCH 2011
Published by WRc plc
Frankland Road
Blagrove
Swindon
Wiltshire
SN5 8YF
on behalf of UK Water Industry Research Ltd
1 Queen Anne’s Gate
London
SW1H 9BT
Y2203 AIN MFN ENG SP Z 0302 AP.A01
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Yorkshire Water Engineering Specification
Section 03.02 CESWI
Copyright
The contents of this document are subject to copyright and all rights are reserved. No part of this document may be
reproduced, stored in a retrieval system or transmitted, in any form or by any means electronic, mechanical,
recording or otherwise, without the prior written consent of the copyright owner.
© UK Water Industry Research Ltd, March 2011
ISBN 9781898920687
Feedback Arrangements
Technical queries should be referred to: CESWI Technical Secretary, WRc plc, Frankland Road, Blagrove, Swindon,
Wiltshire, SN5 8YF
Tel: + 44 (0) 1793 865105
Fax: + 44 (0) 1793 865001
Web: http://ceswi.wrcplc.co.uk
Further Copies
Further copies can be obtained from: WRc plc, Frankland Road, Blagrove, Swindon, Wiltshire, SN5 8YF
Tel: + 44 (0) 1793 865012
Fax: + 44 (0) 1793 514562
Email: publications@wrcplc.co.uk
Web: www.webookshop.com
Y2203 AIN MFN ENG SP Z 0302 AP.A01
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Yorkshire Water Engineering Specification
FOREWORD - SEVENTH EDITION
The Civil Engineering Specification for the Water Industry (CESWI) was first published in July 1978, followed by second,
third, fourth, fifth and sixth editions in August 1984, May 1989, October 1993, July 1998 and June 2004, respectively. It has
become the standard document for civil engineering contracts let by the Water Undertakers and Sewerage Undertakers in
England, Wales and Scotland.
In 2010, a national survey was undertaken to elicit comments on how the sixth edition of the Specification might be improved.
Announcements were subsequently made in appropriate publications and comments were invited from the Water Industry.
In redrafting CESWI, the Working Group adhered to the principles used in the earlier editions; in particular, that the document
should be performance based and that, in letting any contract for civil engineering works, the several documents that form
the Contract are to be taken as being mutually explanatory of one another. CESWI does not, therefore, repeat other nationally
accepted Specifications, rather it refers to them in the relevant Notes for Guidance and in the Appendices.
As in the previous edition, the seventh edition is generic in form and not tied to any particular form of Contract or method of
valuation.
As there is no consistent terminology across the Conditions of Contract most commonly used in the Water Industry, the term
“Client” has been adopted, as a classification independent of the specific conditions of contract, for the terms Employer,
Authority and Purchaser. Similarly, wherever possible, the seventh edition has been re-worded to remove specific reference
to the “Contractor” or “Contract Administrator”, in order to make the seventh edition more flexible with respect to the many
alliancing, joint ventures, and other contracting entities that now carry out work for the Water Industry.
There is no reference in the Specification to satisfy legislation. This follows the general principle that the Works are to be
designed and constructed to comply with all relevant Statutes. A number of Notes for Guidance have been included, where
appropriate.
As with previous editions, it is envisaged that additional Clauses will be added to provide for individual requirements and the
inclusion of such Clauses has been allowed for in the system of numbering, which should be followed when adding any
additional Clauses in order to maintain consistency of presentation. This will be further facilitated by the availability of an
electronic version (see www.wrcplc.co.uk/ceswi).
CESWI 7 is a comprehensive, universal and relevant Specification for the Water Industry. It is compatible with most nationally
produced Engineering Forms of Contract. It remains a valuable foundation document for use throughout the UK Water
Industry.
Y2203 AIN MFN ENG SP Z 0302 AP.A01
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Yorkshire Water Engineering Specification
The Specification was reviewed and redrafted by the following Working Group:
Mike Smith
(Chairman)
Santoro Salvatore
Les Gonzalez
Dominic Wall
Mick Abbott
Iain MacDonald
Mike Fairlamb
John Foster
Kate Harrison
Brian Spencer
Jack McCarey
Don Ridgers
Duncan McKinley-Bourne
Brian Spark
Stuart Lewis
Brian Smith
Sarah Wilcox
(Technical Secretary)
Bristol Water
Jo Hulance
WRc plc
Nick Orman
WRc plc
Julia Trew
WRc plc
Huw Williams
WRc plc
Anglian Water
Dŵr Cymru
Dŵr Cymru
Northumbrian Water
Scottish Water
Severn Trent Water
Severn Trent Water
South East Water
Southern Water
South West Water
Thames Water
United Utilities
Water UK
Wessex Water
Yorkshire Water
WRc plc
Cover designed by WRc plc.
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Yorkshire Water Engineering Specification
CONTENTS
Foreword
Introductory Notes
Product Specifications and Levels of Attestation
NOTE: ALL SUB-SECTIONS ARE PREFIXED BY 03.02
Section
Number
Section
Title
Clause
Number
Clause Heading
1
General
1.1
1.2
1.3
1.4
1.5
1.6
1.7
1.8
1.9
1.10
1.11
1.12
1.13
1.14
1.15
1.16
1.17
1.18
1.19
1.20
1.21
1.22
1.23
1.24
1.25 (N)
1.26 (N)
1.27 (N)
1.28 (N)
1.29 (N)
1.30 (N)
1.31 (N)
Definitions
Accommodation for the contract
Billposting and advertising
British standards and other documents
Tidiness of site
Entry onto the site
Survey of highways, properties and lands
Levels and reference points
Temporary site fencing and gates
Interference with land interests
Interference with any access to property, apparatus or service
Procedure for complaints and claims
Protection against damage
Use of herbicides and pesticides/protection of agricultural land
Works affecting watercourses
Water supply hygiene
Apparatus of statutory undertakers, highway or roads authority
and others
Traffic requirements
Emergency arrangements
Hazardous substances
Environment and sustainability
Customer care
Asset records
Training
Safety on site
Drawings
Contractor’s design
Permanent signage
Alternative / continous supplies
Supply of water
HAUC Highways Authorities Utilities Committee code of conduct
2.1
2.2
2.3
2.4
2.5
2.6
2.7
2.8
2.9
2.10
2.11
2.12
2.13
2.14
2.15
2.16
2.17
2.18
2.19
2.20
2.21
2.22
Materials in contact with potable water
Acrylonitrile-butadiene-styrene (ABS) pipes and fittings
Admixtures for concrete or grout
Aggregates for concrete
Aggregates for high strength concrete wearing screeds
Aggregates for mortar
Asphalt concrete
Biological percolating filter media
Bitumen road emulsions
Bituminous coatings
Bituminous jointing strip
Boards for panelling
Bond breaking compound for dowel bars
Bricks and blocks
Cast stone
Cement
Cement grouts
Clay puddle
Compressible filler and packing for pipelines
Concrete – general
Concrete containing PFA or GGBS
Concrete – ready-mixed
2
Materials
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2.23
2.24
2.25
2.26
2.27
2.28
2.29
2.30
2.31
2.32
2.33
2.34
2.35
2.36
2.37
2.38
2.39
2.40
2.41
2.42
2.43
2.44
2.45
2.46
2.47
2.48
2.49
2.50
2.51
2.52
2.53
2.54
2.55
2.56
2.57
2.58
2.59
2.60
2.61
2.62
2.63
2.64
2.65
2.66
2.67
2.68
2.69
2.70
2.71
2.72
2.73
2.74
2.75
2.76
2.77
2.78
2.79
2.80
2.81
2.82
2.83
2.84
2.85
2.86
2.87
2.88
2.89
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Concrete – porous no-fines
Concrete – air-entrained
Concrete – chloride content
Concrete –pipes and fittings
Connectors for timber
Coping units
Copper pipes and fittings
Cover blocks and spacers for reinforcement
Damp-proof courses
Doors, frames and linings
Dowel bars
Draw cord
Dressed natural stone kerbs, channels, quadrants and setts
Ductile iron, cast iron and steel pipes, flanges and fittings
Electrodes, filler rods and wires for welding
Expanded metal angle beads
Fertiliser
Field gates
Fixing accessories for building purposes
Fixings for metalwork
Flashings
Flexible couplings
Floor tiles
Foamed concrete
Foam swabs
Gabions and rockfill mattresses
Gaskets for flanged joints and push-fit joints
General filling materials
Glass for glazing
Glass reinforced plastics (GRP) pipes and fittings
Glass reinforced plastics products
Glazing materials
Granular sub-base material
Grass seed
Grummets
Gullies and gully cover slabs
Gully covers, gratings and frames
Handrails and balusters
Hydrants
Imported topsoil
Imported turf
Industrial flooring, walkways and stair treads
Joinery timber
Joint filler board
Joint sealing compounds and sealants
Joint seals and lubricants
Joist hangers
Ladders
Lead
Lime for mortar
Lintels
Manhole covers and frames
Manhole steps
Marker tape and marker posts
Mastic asphalt
Mechanical couplings for pipelines and fittings
Metal lathing
Metal ties
Mineral aggregates for flat roofs
Mortar
Nails
Natural stone
Non-man access chambers
Nuts, screws, washers and bolts
Packings for tunnels
Paints and painting materials for buildings
Permanent fencing
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3
Excavation,
backfilling and
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2.90
2.91
2.92
2.93
2.94
2.95
2.96
2.97
2.98
2.99
2.100
2.101
2.102
2.103
2.104
2.105
2.106
2.107
2.108
2.109
2.110
2.111
2.112
2.113
2.114
2.115
2.116
2.117
2.118
2.119
2.120
2.121
2.122
2.123
2.124
2.125
2.126
2.127
2.128
2.129
2.130
2.131
2.132
2.133
2.134
2.135
2.136
2.137
2.138
2.139
2.140
2.141
2.142
2.143 (N)
2.144 (N)
2.145 (N)
2.146 (N)
2.147 (N)
2.148 (N)
2.149 (N)
2.150 (N)
2.151 (N)
2.152 (N)
2.153 (N)
Pipe surround materials
Pipes for ducts
Pipes for land drainage and temporary drains
Plaster
Plastic chambers and rings
Plastic sheeting
Plywood
Polyethylene pipes and fittings
Precast concrete slabs and cover frame seating rings
Precast concrete flags and paving blocks
Precast concrete kerbs, channels, edgings and quadrants
Precast concrete manholes and soakaways
Precast concrete box culverts
Precast concrete segments for tunnels and shafts
Precast concrete setting blocks for pipes
Precast concrete tanks
Prestressed concrete pipes and fittings
Prestressed precast concrete floors
Profiled steel sheeting
Propylene co-polymer pressure pipes
PTFE tape
Pulverised-fuel ash
Rainwater pipes and gutters
Rolled asphalt
Roof coverings
Safety chains in sewers
Sample taps
Sands
Sewer linings
Soil, waste and ventilating pipes
Steel reinforcement
Steel sheet piles
Stiles, bridle gates and kissing gates
Structural steel
Surface boxes and guards
Synthetic resin adhesives
Timber and preservation of timber
Trees and shrubs
Tying wire
Unplasticised PVC pipes and fittings
Valves and penstocks
Vitreous enamel tanks
Vitrified clay pipes and pipeline fittings
Wall tiles
Water
Water fittings and appliances
Waterstops
Wet-mix macadam
Windows
Window sills
Wood flooring
Wood trim
Wrought aluminium and aluminium alloy
Surface hardeners to concrete floor
Dissimilar metals
Thermal insulation
Pipework
Protective coating to concrete
Ground granulated blast furnace slag
Pipework identification
Pre-cast post-tensioned concrete tanks
Storage of materials
The employer’s materials framework supplier performance
Surplus material
3.1
3.2
Excavation
Relaying turf
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restoration
3.3
3.4
3.5
3.6
3.7
3.8
3.9
3.10
3.11
3.12
3.13
3.14
3.15
3.16
3.17 (N)
3.18 (N)
3.19 (N)
3.20 (N)
3.21 (N)
3.22 (N)
3.23 (N)
3.24 (N)
Topsoil for re-use
Dealing with water
Temporary drains
Backfilling
Reinstatement of maintainable highways
Reinstatement of non-maintainable highways
Reinstatement of unpaved land
Trees
Reinstatement in highways and roads using foamed concrete
Land drains
Filling above ground
Blasting
Piling
Demolition
Hedges
Private roads
Reinstatement of defects
Reinstatement of private land
Reinstatement of surface features
Signing/lighting/guarding
Unmade roads
Walls
4
Concreting and
formwork
4.1
4.2
4.3
4.4
4.5
4.6
4.7
4.8
4.9
4.10
4.11
4.12
4.13
4.14
4.15
4.16
4.17
4.18
4.19
4.20
4.21
4.22
4.23
4.24
4.25
4.26
4.27
4.28
4.29 (N)
4.30 (N)
Supply of information
Initial testing
Identity testing
Porous no-fines concrete
Transporting, placing and compacting
Concreting in cold weather
Concrete temperature
Curing
Records of concreting
Construction of formwork
Cleaning and treatment of forms
Striking of formwork
Sloping formwork
Cutting and bending of reinforcement
Fixing of reinforcement
Surface condition of reinforcement
Laps and joints
Welding of reinforcement
Built-in items
Construction joints
Surface finishes produced without formwork
Surface finishes produced with formwork
Wearing screeds
Tie bolts for formwork
Tolerance for concrete surfaces
Grout quality control testing
Fibre reinforced concrete
Concrete repairs
Scabbling
Consistence
5
Construction of
pipelines and
ancillary works
5.1
5.2
5.3
5.4
5.5
5.6
5.7
5.8
5.9
5.10
5.11
5.12
Pipelaying generally
Pipe bedding
Concrete protection to pipes
Pipe surround
Pipelaying in headings
Thrust blocks
Pipe jointing generally
Welded joints in polyethylene pipes
Flanged joints
Ogee joints
Welded joints in steel pipes
Cement mortar joints
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5.13
Run lead joints
5.14
Protection of ferrous pipes, joints and fittings
5.15
Cutting pipes
5.16
Precast concrete manholes
5.17
Brickwork manholes and chambers
5.18
Inverts and benching
5.19
Pipes and joints adjacent to structures
5.20
Watertightness of manholes and chambers
5.21
Setting manhole covers and frames
5.22
Connections to existing sewers
5.23
Sewers and manholes to be abandoned
5.24
Junctions and laterals on sewers
5.25
Marker and indicator posts
5.26
Tolerances for pipelines
5.27
Cable ducts
5.28
Installation of valves
5.29
Washouts
5.30
Alternative pipe installation techniques
5.31
Connections to existing water supply pressure pipelines
5.32
Temporary water supply mains
5.33
Water mains to be abandoned
5.34 (N)
Street furniture
5.35 (N)
General pipe and fittings repair and installation techniques
5.36 (N)
Maintenance of electrical continuity of service pipes
5.37 (N)
Service pipe blockages
5.38 (N)
Temporary Service Connections
5.39 (N) Requirements for the Position of Fittings on Distribution Mains
(not Trunk Mains)
6
Building works
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6.1
6.2
6.3
6.4
6.5
6.6
6.7
6.8
6.9
6.10
6.11
6.12
6.13
6.14
6.15
6.16
6.17
6.18
6.19
6.20
6.21
6.22
6.23
6.24
6.25
6.26
6.27
6.28
6.29
6.30
6.31
6.32
6.33
6.34
6.35
6.36
6.37
Brickwork and blockwork generally
Brickwork and blockwork, jointing and pointing
Cavity walls
Damp-proof courses
Corbelling
Bonding to concrete
Underpinning
Centering and lagging
Bricklaying and blocklaying in cold weather
Preparation for plastering
Fixing of plasterboard
Plastering
Plastering in cold weather
Concrete floor finishes
Floor tiling
Terrazzo floor finishes
External rendering
Wall tiling
Carpentry and joinery
Structural steelwork
Roofs
Timber floors
Door frames
Windows
Glazing
Painting
Slating and tiling
Lightweight concrete roof screeds
Asphalt roofing
Bitumen felt roofing
Plumbing
Openings in walls, floors and ceilings
Tolerances for building works
Electrical installations
Profiled steel cladding
Precast concrete floors
Composite floors
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7
Testing and
disinfection
6.38 (N)
Ironmongery
7.1
7.2
7.3
7.4
7.5
7.6
7.7
7.8
7.9
7.10
7.11
7.12
7.13
7.14
7.15
7.16
7.17
7.18
7.19 (N)
7.20 (N)
7.21 (N)
7.22 (N)
7.23 (N)
7.24 (N)
7.25 (N)
Cleansing and swabbing of pipelines
Precautions prior to testing pipelines
Testing method programme and notification
Testing non-pressure pipelines
Water test for non-pressure pipelines
Air test for non-pressure pipelines
CCTV inspection of pipelines
Infiltration
Testing of ductile iron, PVC, GRP and steel pressure pipelines
Testing of polyethylene pressure pipelines
Disinfection of water mains
Cleansing of structures
Testing of concrete roofs
Testing of concrete structures designed to retain an aqueous liquid
Disinfection of structures for potable water
Water for testing, swabbing and disinfection
Disposal of water from cleansing, testing or disinfection
Testing of non-concrete structures for retaining aqueous liquids
Testing and disinfection of service connections and pipes
Disinfection, sampling and operation of water mains
Sampling from standpipes, filling of potable water containers from
standpipes
The use of potable water containers
Disinfection, filling and use of bowsers
Pressure testing of service pipes
Regulatory potable water sample points
8
Roadworks
8.1
8.2
8.3
8.4
8.5
8.6
8.7
8.8
8.9
8.10
8.11
8.12
8.13
8.14
8.15
8.16
8.17
Road formations
Sub-base construction
Wet-mix macadam construction
Lean concrete construction
Laying coated macadam
Laying hot rolled asphalt
Waterproof underlay for concrete carriageways
Reinforcement of concrete carriageways
Laying concrete carriageways
Laying kerbs and channels
Foundations for footways
Laying concrete paving flags
Laying paving blocks
Tolerances for finished carriageway surfaces
Fixing of gullies
Lining and signage
Concrete footways
9
Sewer renovation
9.1
9.2
9.3
9.4
9.5
9.6
9.7
9.8
9.9
9.10
9.11
9.12
9.13
9.14
9.15
9.16
9.17
9.18
9.19
Isolation of flows
Preparatory survey
Preparation of sewers
Jointing generally
Connections
Chambers
Release of curing water
Annulus grouting generally
Inspection after grouting
Lining through flow control devices
Inspection after renovation
Lining template
Lining design
Tolerances for preformed linings
Cutting and protection of linings
Man-entry preformed GRP and GRC units
Cured-in-place lining systems
Rendering and local repairs
Patch repairs
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9.20
9.21
9.22 (N)
Styrene fumes
Spray lining
Sewer Handover
10
Water mains
rehabilitation
10.1
10.2
10.3
10.4
10.5
10.6
10.7
10.8
10.9 (N)
10.10 (N)
10.11 (N)
10.12 (N)
Preparatory survey
Preparation of water mains
In-situ linings
Sliplining and replacement moling
Connections
Lining through valves
Inspection after in-situ re-lining
Bringing rehabilitated water mains into service
Rapid setting polymeric lining
Sliplining and close fit lining
Air scouring
Liners to pipes in dams
11
Tunnelling and shaft
sinking works
11.1
11.2
11.3
11.4
11.5
11.6
11.7
11.8
11.9
11.10
11.11
11.12
11.13
11.14
11.15
11.16
11.17
11.18
Headings, tunnels and shafts
Shafts
Openings in shafts and tunnels
Segmental shaft and tunnel linings
Unbolted concrete tunnel segments
Bolted concrete segmental linings
Grouting of segments
Caulking
Pointing of joints
Secondary linings to segments
Watertightness of shafts and tunnels
Control of groundwater
Pipe jacking
Microtunnelling
Ventilation of tunnels and shafts
Work in compressed air
Recording of information
Tolerances for shafts, tunnels and pipe jacks
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INTRODUCTORY NOTES
1.
The Foreword, Product Specifications and Levels of Attestation, Notes for Guidance and Appendices are not part of
the Specification and do not affect the interpretation either of the Specification or of any other Contract documents.
2.
The following principles, which reflect current engineering practice within the Water Industry, have been followed in
drafting this substantially revised edition of the Specification:
(i)
The Specification is written primarily in terms of the performance required, leaving the Constructor, so far as
possible, free to decide his method of working.
(ii)
The document is intended for use with most engineering types of Contract within the Water Industry for the
construction of civil engineering works. As such, it is not associated with any particular Conditions of Contract.
(iii)
The Specification is generic in nature and is intended for use in conjunction with whatever method of valuation
is used.
(iv)
There is no reference in the Specification either to the method of assessing payment or to who should bear
specific costs. These matters are left for inclusion in the relevant Contract.
(v)
Wherever other explicit and relevant documents are available, they are referred to rather than repeated in the
Specification.
(vi)
References to Acts of UK Parliament and Statutory Instruments are generally omitted from the main text
(though not from the Notes for Guidance), since compliance with Statute is a general legal requirement.
(vii) Traditional requirements which are desirable but impossible to achieve in a literal sense have been omitted
(e.g., “pipes to be laid true to line and level”).
(viii) All actions are to be carried out by the Constructor unless otherwise stated in the Specification.
3.
Notes for Guidance are printed in the margins beside the text to which they refer and are designed primarily to assist
those preparing Contract documents. One of their main purposes is to explain apparent omissions from the text, such
as those referred to in Note 2 above, and to cross-refer to other documents where such matters are covered.
4.
Acts of Parliament, Statutory Instruments and other documents quoted in the Notes for Guidance and the Appendices
are those in force at the time of publication.
5.
Reference to Clause Numbers in the main text and in the Notes for Guidance relate to Clause Numbers of this
Specification.
6.
It is recommended that the boundaries and limitations of the Works included in the Contract are described at the
beginning of the Specification for the particular Contract, and should include items such as:
7.
(i)
The Site and access; drawing reference showing boundaries.
(ii)
Sections of the Works; full description.
(iii)
Other Contracts; lists of work content, areas and timings.
(iv)
Operational restrictions; Site rules and requirements.
(v)
Client-supplied materials; list of what, when and from whom.
(vi)
Constructor design; definition of the parts that the Constructor is to design and the standard(s) required.
All Works should be carried out with the objective of causing a minimum amount of disturbance to the environment,
especially where there is a large environmental interface.
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PRODUCT SPECIFICATIONS AND LEVELS OF ATTESTATION
The Utilities Directive (2004/17/EC) on the Procurement Procedures of Entities Operating in the Water, Energy, Transport
and Postal Services Sectors came into force on 30 March 2004. Article 34 of this Directive details the requirements of this
Directive regarding the use of Standards.
When specifying the requirements of any product, the following procedure is used:
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A relevant EN is any EN covering the subject in question which is in force in the EU. In the UK, ENs are published as
BS ENs. A Water Industry Specification may be used where there is no relevant EN, BS or equivalent available.
A European Standard, British Standard or equivalent will not normally be available in the case of newly-developed
products but this is not to be seen as inhibiting the use of such products. Water Industry Specifications, issued by the
Water UK Standards Board, deal with products such as these and are called up in the Specification. However, in the
case of any innovatory product for which no European Standard, British Standard or Water Industry Specification (or
the equivalent of either) exists, care should be taken to ensure that the product is fit for purpose. This might be achieved
by using products which have been assessed by an independent body. The British Board of Agrément (BBA) is
authorised to issue European Technical Approvals under the provisions of the Construction Products Directive
(89/106/EEC).
Under the provisions of the Construction Products Directive (89/106/EEC), the European Commission decides the
appropriate level of attestation when a harmonised European Specification is published under a mandate given in
connection with that Directive. The Specification, therefore, now provides for Levels of Attestation less stringent than
full Third Party Certification, where so decided by the Commission.
Where the product is also covered by a Mandate under the provisions of the Construction Products Directive
(89/106/EEC), the relevant system of conformity attestation chosen by the Commission of the European Community
(CEC), and leading to the use of the CE mark for a product, applies to those elements of the product specification which
relate to the Mandate. Third Party Certification is recommended as a cost-effective means of ensuring compliance with
Standards. However, Water Industry policy is for individual purchasers to determine where Third Party Certification is
required.
Additional quality assurance requirements, including Third Party Certification, may be sought by the purchaser as a
cost-effective means of ensuring compliance with Standards. BSi Kitemarking is an example of Third Party Certification.
Currently, where European Standards refer to requirements for the effect of materials on potable water quality, National
Regulations apply. Before accepting any material which will come into contact with potable water or water to be used
for potable supply, the Client will have regard to the provisions of:
a) For England:
Water Supply (Water Quality) Regulations 2010 (SI 2010 No. 994 (W.99)).
(b) For Scotland:
Water Supply (Water Quality) (Scotland) Regulations 2001 (SI 2001/207).
(c) For Northern Ireland:
Water Supply (Water Quality) Regulations (Northern Ireland) 2002 (SR 2002/331).
Reference should be made to the current list of approved substances prepared by the Drinking Water Inspectorate.
Reference should also be made to the ‘Water Fittings and Materials Directory’, published by the Water Regulations
Advisory Scheme Ltd on its website (www.wras.co.uk/dorectory).
Requirements for the testing of materials for use in contact with potable water are dealt with in:
i)
DD 256 for metallic materials.
ii)
BS 6920-1 for non-metallic materials.
Due consideration should be given to selecting materials which promote sustainability and minimise environmental
impact.
Y2203 AIN MFN ENG SP Z 0302 AP.A01
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Y2203 AIN MFN ENG SP Z 0302 AP.A01
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Yorkshire Water Engineering Specification
Section 1 - General
SECTION 1
GENERAL
The Notes for Guidance are not part of the
Specification
1.1 DEFINITIONS
(i) The Contract could be a construction agreement
e.g., NEC or IChemE, or an adoption agreement, e.g.,
Self Laying of Water Mains and Services.
1. This Specification is written on the assumption that the
Party entering into a Contract that includes this
Specification will be bound by the Specification terms and
be responsible for following its provisions.
2. “Party” means a company, contractor, alliance, joint
venture, consortium, etc.
3. “Client” means the person or persons, firm, company or
other body for whom the Works are to be constructed and
includes the Client’s
personal representatives,
successors and permitted assignees.
4. “Environmental Regulator” means in England and
Wales, the Environment Agency (EA), in Scotland, the
Scottish Environmental Protection Agency (SEPA) and in
Northern Ireland, the Northern Ireland Environment
Agency (NIEA).
5. “River Authority” means in England and Wales, the
Environment Agency (EA), in Scotland, the Scottish
Environmental Protection Agency (SEPA) and in Northern
Ireland, the Department for Agriculture and Rural
Development.
6. The “Highway Reinstatement Specification” means in
England, ’Specification for the Reinstatement of Openings
in Highways’, Department for Transport and published by
HAUC. In Scotland it means the ‘Specification for the
Reinstatement of Openings in Roads’ the Scottish
Government. In Wales it means ’The Specification for the
Reinstatement of Openings in Highways (2nd Edition),
Welsh Assembly Government.
Yorkshire Water Services Ltd:
1.1.3 (S)
The “Client” means the Employer who is
Yorkshire Water Services and includes the
Employer’s personal representatives and
permitted assignees.
The Employer’s
contact is named in the Contract Data.
1.1.7 (A)
All Clauses that require notice to be given,
Contractors
shall
require
the
Representative to give notice to the
Employer via the NEC Project Manager or
other permitted assignee.
1.1.8 (A)
The “Constructor and Contractor” means
the Contractor to whom the Contract has
been awarded by the Employer and
includes the Contractor’s representatives
and permitted assignees. The Contractor
is named in the Contract Data.
1.1.9 (A)
“Particular Specification” means the
specification prepared by the Contractor as
part of the Works Information for the
Contractor’s design, to detail the
Employer’s requirements for the design,
construction and testing of the Works.
additional (A), new (N) or substitute (S) clauses.
Yorkshire Water Services Ltd additional, new or
substitute clauses.
CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
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Section 1 - General
1.2 ACCOMMODATION FOR THE CONTRACT
(i) Consent of the Local Planning Authority may be
required for Site accommodation.
(ii)
BS
6767-1
deals
accommodation units.
with
transportable
(iii) Reinstatement is covered in Clause 3.9.
(iv) Details of accommodation and disposal of all
domestic types of waste should be stated in the
Contract.
(v) Any special insurance requirements should be a
Special Condition of Contract.
1. Until the completion of the Works, accommodation and
parking facilities, as described in the Contract, shall be
equipped and maintained. Accommodation shall be
erected, furnished, equipped, fully serviced and ready for
use within 7 days of the work commencing on Site.
2. Where movable offices are required by the Contract,
these shall be relocated as directed under the terms of the
Contract.
3. Where the Contract requires telephone facilities to be
provided, such facilities shall have separate connections
with privacy of conversation.
(vi) The siting and availability of all accomodation
should be stated in the Contract.
4. All Site accommodation, services and parking shall be
removed upon completion of the Works or at such other
date as directed under the terms of the Contract.
Yorkshire Water Services Ltd additional, new or
substitute clauses.
1.2.5 (A)
Planning approval for accommodation, not
related to the facilities provided by the
Employer, shall be obtained by the
Contractor.
1.3 BILLPOSTING AND ADVERTISING
(i) Notice boards or scheme signboards required by
the Client should be detailed in the Contract.
1. Billposting or advertising of any kind shall not be
undertaken, unless otherwise stated in the Contract.
(ii) Notice boards and signboards should be erected
and maintained by the Contractor at a location and in
the form, layout and number as specified in
accordance with the Contract.
(iii) Consent of the Local Planning Authority may be
required for notice boards or signboards.
Yorkshire Water Services Ltd additional, new or
substitute clauses.
1.3.2 (A)
Scheme signboards shall be erected and
maintained by the Contractor at a location
and in the form, layout and number as
required by the Employer. All signboards
shall be in accordance with Yorkshire
Water Services Identity Guidelines.
1.4 BRITISH STANDARDS AND OTHER DOCUMENTS
(i) Any particular requirements should be described in
the Contract after taking due account of the guidance
in the Product Specifications and Level of Attestation
at the front of CESWI.
(ii) Where appropriate, use should be made of any
technical and advisory services offered by
manufacturers.
1. British Standards and other documents referred to in
the Contract shall be deemed to be those current 28 days
prior to the date for return of Tenders.
2. Any reference in the Contract to a Standard published
by the British Standards Institution, or to the Specification
of another body, shall be construed equally as reference
to an equivalent one.
1.5 TIDINESS OF SITE
(i) Special storage requirements should be described
in the Contract.
1. Materials, plant and equipment shall be positioned,
stored and stacked in an orderly manner.
2. All pipes and fittings shall be stored off the ground, in a
clean environment to prevent any contamination of
materials prior to their use.
3. All Site waste and surplus shall be removed from Site.
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Section 1 - General
4. Pipe end caps shall be fitted at either end of the pipe,
until the pipe is used in the Works, to prevent vermin
entering.
Yorkshire Water Services Ltd additional, new or
substitute clauses.
Yorkshire Water Services Ltd additional, new or
substitute clauses.
1.5.5 (A)
The Contractor shall ensure that the
appearance of the site is at all times clean
and tidy. All debris, deposits and staining
shall be removed immediately following the
work activity. The clean-up may include for
the use of a jet washer or road sweeper.
1.5.6 (A)
Site housekeeping shall at all times
consider safety and security. In particular
the Contractor shall ensure perimeters are
kept secure, climbing aides and ladders
are stored appropriately, and items of high
value or which are otherwise attractive to
thieves or trespassers are kept out of site.
Further details on site security can be
found in Section 03.07 of the Engineering
Specification.
1.6 ENTRY ONTO THE SITE
(i) The Contract should prescribe the extent of the
Site, including working areas, accesses and the
periods for which they will be available. Reference
should be made to any known hazards.
(ii) The Client may have to obtain planning permission
where an access from a classified road or street is
specified.
(iii) It should be assumed that formal entry notices
have already been served by the Client, and owners
and occupiers have been alerted to impending entry.
(iv) The Contract should describe any Code of
Practice or other relevant documentation in
connection with pipelaying on private land.
(v) Any requirements for entry on third party land,
including any notice required, should be specified in
the Contract.
1. The Client shall, at all reasonable times, have access
to the Works and to the Site and to all workshops and
places where work is being prepared or from where
materials, manufactured articles and machinery are
obtained for the Works, and every facility for, and every
assistance in, obtaining such access or the right to such
access shall be afforded.
2. Records shall be kept of the dates of the entry onto and
departure from all property and lands of each owner and
occupier.
3. Records shall be kept of the dates of the erection and
removal of all enclosures.
4. Copies of these records shall be provided as specified
in the Contract. Copies of similar records in respect of
roads, footpaths and thoroughfares shall be kept.
5. No part of the Site shall either be entered or used for
any purpose unconnected with the Works.
Yorkshire Water Services Ltd additional, new or
substitute clauses.
1.6.2 (S)
Where work is to be undertaken on a
private road or street the Contractor shall
identify and communicate the nature of the
work to all owners and occupiers of the
land and properties which front upon it.
Communication shall be established with
the parish council, or with the district
council (where there is no parish council)
where there is likely to be public interest or
involvement. Notices for private streets
are issued to the street manager and all
affected house holders with a copy set to
the local Street Authority to be held on their
street works register.
Yorkshire Water Services Ltd additional, new or
substitute clauses.
1.6.6 (A)
The Contractor shall adhere to the
procedures for land entry as advised by the
Employers Land and Planning Department
and as laid out in the document "Exercise
CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
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Section 1 - General
of Pipelaying Powers on Private Land
LENS Land Entry Notices Database and
Guidance booklet".
The Land Entry
Notices Database (LENS) shall be used by
all parties requiring entry onto private land.
1.6.7 (A)
Arrangements shall be made by the
Contractor to move parked vehicles
obstructing access to the planned areas of
work.
1.6.8 (A)
Where works require the removal of any
existing physical barrier to prevent persons
and/or animals (Pets / Livestock) from
entering Roads (High and Low Speed),
Waterways, Network Rail Property and/or
any other place of danger, this shall be
done with the agreement of the barrier
owner and all necessary steps shall be
taken to ensure the safety of the public,
until such time as the permanent barrier
can be replaced.
1.6.9 (A)
The Contractor shall assess his obligations
in respect of entry onto private land in
accordance with the requirements set out
in Volumes 1-3 of the Engineering
Specification. The Contractor shall comply
with the YWS Guidance Notes for
Construction Activity in Agricultural
Land/Countryside and the Code of
Practice for the Exercise of Pipelaying
Powers on Private Land (CoP). Both these
documents are available from Yorkshire
Water’s Programme Team, Land, Property
and Planning, Western House, Bradford
1.7 SURVEY OF HIGHWAYS, PROPERTIES AND
LAND
(i) The composition and extent of the survey should be
detailed in the Contract and may include photographs,
video recordings, sketches and professional reports.
(ii) The Contract should describe any special
requirements for land used for organic farming.
(iii) The format of the survey record photographs
should be stated in the Contract.
1. Prior to entry, and where appropriate, surveys shall be
carried out of the condition of highways, properties, lands
including trees, boundaries, crops and any other features
which may be affected by the Works.
2. The survey shall be carried out with the responsible
Highway Authority and owners or occupiers.
3. A representative selection of photographs shall be
provided in a digital format (CD or DVD) for the purpose
of the survey record. Each photograph shall be uniquely
numbered and dated.
4. All photographs/records shall be signed by the
landowner as a true record of the condition of the property
and land, prior to the commencement of the Works.
Yorkshire Water Services Ltd additional, new or
substitute clauses.
CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
1.7.3 (S)
A representative selection of photographs
shall be provided in a digital format (CD or
DVD) for the purpose of the survey record.
Each photograph shall be uniquely
numbered and dated, in colour and of
sufficient resolution to ensure clarity.
1.7.4 (S)
Where required by the Contract,
photographs/records shall be signed by
the landowner or landowner’s agent as a
true record of the condition of the property
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Section 1 - General
and land, prior to the commencement of
the Works.
1.8 LEVELS AND REFERENCE POINTS
(i) The Contract should prescribe the datum level for
the Works, together with any master benchmarks.
Precise reference of the Works to existing features or
to the Ordnance Survey National Grid should be
shown.
1. Details shall be provided of the level and location of the
temporary benchmarks and reference points which are
proposed to be used.
(ii) Local differences can arise between GPS and OS
coordinates.
Yorkshire Water Services Ltd additional, new or
substitute clauses.
1.9 TEMPORARY SITE FENCING AND GATES
(i) The location and type of fencing including access
and gates, should be detailed in the Contract.
1. The Site shall be adequately fenced.
2. Where the type and locations of temporary site fencing
and gates are described in the Contract, such fencing and
gates shall be erected before commencing any other work
in that portion of the Site.
3. All Site fencing and gates shall be regularly inspected
and maintained, and any defects made good without
delay. Access shall be provided in temporary Site fencing
and gates, as necessary, for the use of the occupiers of
adjacent lands.
4. Temporary Site fencing and gates shall remain in
position until either they are replaced with permanent
fencing and gates, or the Works are sufficiently completed
to enable that portion of the Site to be brought into use.
Yorkshire Water Services Ltd additional, new or
substitute clauses.
1.9.5 (A)
The
Contractor
shall
liaise
with
Landowners and Occupiers along the
pipeline route/ area of the Works in order
to determine the requirements for
temporary site fencing.
1.9.6 (A)
Unless agreed otherwise with the
Landowner, Occupier or Employer,
temporary site fencing for pipeline
installations shall be erected on all sites in
line with the following acceptable
standards.
Type of Land
Acceptable Standard
Arable Land
Post and Wire (Four
Strand)
Stock Land
Post and Rail or
Post and Wire (Four
Strand or Mesh) +
electric
Urban Land or Site Works
(excluding roadways)
1.9.7 (A)
CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
Page 20 of 192
Heras type Fencing
Where possible the Contractor should try
and negotiate with the landowner or tenant
to forego the fences and stock-proof
fencing and move his stock to another field
that is not being disturbed by the works.
This may result in a payment to the
landowner or tenant but will be better value
Version 20 – April 2020
Yorkshire Water Engineering Specification
Section 1 - General
than constructing and removing gates and
fences.
1.10 INTERFERENCE WITH LAND INTERESTS
(i) All land required for the Works should be prescribed
in the Contract. Additional land or interests found
necessary to carry out the Works may need to be
obtained, including any associated planning consent.
1. Constructional operations shall be confined within the
Site, or such other areas of land as may be negotiated.
No trespass or breach of any rights, bye-laws or
regulations shall take place.
(ii) The Contract should describe any special
precautions necessary to comply with the Client’s
obligations.
2. Subject to any unavoidable disturbance which may be
necessitated by the execution of the Contract, any rights
which may be enjoyed on or near the Site shall not be
interfered with.
(iii) The availability and location of accommodation
and storage areas outside the Site should be stated in
the Contract.
3. Before exercising any right negotiated in connection
with wayleaves, easements or accommodation outside
the Site, written notification of such arrangements shall be
provided prior to entry.
1.11
INTERFERENCE WITH ANY ACCESS TO
PROPERTY, APPARATUS OR SERVICE
1. The access requirements shall be identified in the
Contract and provided in advance of any property,
apparatus or service being affected by the Works.
Alternative arrangements shall be provided before
interfering with any access to property, apparatus or
service. Affected owners and occupiers shall be notified,
in writing, 14 days in advance of any such interference
and it shall be confirmed that alternative arrangements
have been agreed.
2. Should it become impractical to maintain vehicular
access to any property, apparatus or service at any time
during the construction of the Works, alternative
arrangements shall be provided and maintained. Every
assistance shall be provided to the owner/occupier or
tenant affected by the Works to enable them to undertake
all aspects of their normal activity.
3. The access and service requirements of those with
special needs shall be taken into account.
4. Work in the highway shall be planned and carried out
to minimise the disruption to access for local residents.
Safe pedestrian access to all properties shall be
maintained at all times.
Yorkshire Water Services Ltd additional, new or
substitute clauses.
CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
1.11.1 (S)
The access requirements shall be
identified in the Contract and provided in
advance of any property, apparatus or
service being affected by the Works.
Alternative arrangements shall be provided
before interfering with any access to
property, apparatus or service. Affected
owners and occupiers shall be notified of
all planned works in writing 14 days in
advance of any such interference.
Confirmation of alternative arrangements
shall be agreed and recorded in the
Employers
Information
Technology
Systems.
1.11.5 (A)
Before interfering with access to any
property, apparatus
or service, the
Contractor shall discuss the works with the
occupier and any other parties affected to
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Section 1 - General
ensure their requirements are met and any
appropriate access notices are given.
Confirmation
that
such
alternative
arrangements have been agreed with the
occupier or others shall be recorded with
the job in the Information Technology
Systems.
1.12 PROCEDURE FOR COMPLAINTS AND CLAIMS
(i) The Contract should define the meaning of
“promptly” in accordance with the service objectives of
the Client.
1. Immediately following any damage or injury arising from
the execution of the Works, written notification shall be
provided without delay to the Client.
(ii) The Contract should define any specific
requirements for logging and dealing with complaints
and correspondence, in line with Regulatory
requirements.
2. Details of all complaints, claims or warnings of intended
claims received from third parties shall be notified without
delay to the Client.
Yorkshire Water Services Ltd additional, new or
substitute clauses.
1.12.4 (A)
The Contractor shall comply with the
Employer’s
complaints
and
claims
procedures.
1.12.5 (A)
The Contractor shall comply with the
Employer’s 3rd party claims procedure.
3. Any complaints, claims, damage or injury by owners or
occupiers shall be dealt with promptly.
1.13 PROTECTION AGAINST DAMAGE
(i) Any permanent support known to be required
should be described in the Contract.
(ii) NJUG (National Joint Utilities Group) Publication
Volume 4 ‘Guidelines for the Planning, Installation and
Maintenance of Utility Services in Proximity to Trees’
gives guidance on working near trees.
1. All necessary precautions shall be taken to avoid
causing any unwarranted damage to highways, roads,
properties, lands, trees, roots, crops, boundaries and any
other features, and the apparatus of Statutory
Undertakers, the Highway or Roads Authority and other
parties.
2. Where any portion of the Works is close to, across or
under any existing apparatus of Statutory Undertakers,
the Highway or Roads Authority or other parties,
temporary support shall be provided and work carried out
around, under or adjacent to all apparatus in a manner
designed to avoid damage, leakage or danger, and to
ensure uninterrupted operation.
3. The Client and the Statutory Undertaker, Highway or
Roads Authority or owner concerned, as appropriate,
shall be notified should any leakages or damage to
existing services, highways or roads be discovered, and
every facility shall be afforded for the repair or
replacement of the apparatus affected.
Yorkshire Water Services Ltd additional, new or
substitute clauses.
CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
1.13.4 (A)
The Contractor shall comply with NJUG
publication volume 4 ‘Guidelines For The
Planning, Installation And Maintenance Of
Utility Services In Proximity To Trees’
together with BS 5837:2005 Trees in
Relation to Construction. Where conflict
arises refer to the British Standard.
1.13.5 (A)
In accordance with clauses 1.13.1, 1.13.2
and 1.13.3 Yorkshire Water Services Ltd.
shall also be regarded as a Statutory
Undertaker and as such shall be afforded
all rights and protections under the above
clauses.
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1.13.6 (A)
The Contractor shall fully comply with The
Hedgerow Regulations 1997 and all its
amendments.
1.13.7 (A)
The Contractor shall give a minimum of 14
days’ notice of his intention to remove a
tree or vegetation and shall not proceed
with the removal of trees or vegetation
without the permission of the Employer.
1.13.8 (A)
The Contractor shall ensure that any water
supplies, drainage systems or other
services affected by the Works shall be
maintained, or an equivalent provided,
throughout the period of the Works.
1.13.9 (A)
The Contractor shall bear the cost of the
repair and making good of any damage
caused by his Works. Any damage caused
to private or public property shall normally
be repaired immediately and in all cases
within a maximum of 7 days.
1.14
USE
OF
HERBICIDES
AND
PESTICIDES/PROTECTION OF AGRICULTURAL LAND
(i) Where necessary, the Contract should detail the
requirements to prevent the spread of agricultural,
animal and poultry diseases, including any restrictions
on movement of materials.
(ii) The document ‘Every Drop Counts – Keeping
Water Clean’ by the Crop Protection Association gives
guidelines on the use of pesticides.
Yorkshire Water Services Ltd additional, new or
substitute clauses.
1. Details of all herbicides and pesticides proposed for use
shall be submitted to the Client for approval.
2. All pesticides shall be selected from the list of approved
pesticides published by DEFRA, the Scottish Government
and the Welsh Assembly.
1.14.3 (A)
DEFRA must be consulted where there
may be a risk of the spread of agricultural,
animal and poultry diseases.
1.14.4 (A)
Reference should be made to the DEFRA
Code of Good Agricultural Practice
‘Protecting our Water, Soil and Air
1.15 WORKS AFFECTING WATERCOURSES
(iii) The following Statutory provisions may also be
relevant:
(a) Impeding Flow in a Watercourse: Water
Resources Act 1991, Section 107, and Land Drainage
Act 1994,
(b) Pollution of a Watercourse or Underground Strata:
Water Resources Act 1991, Sections 85, 86 and 90,
Salmon and Fresh Water Fisheries Act 1975, Section
4;
(c) Environmental Protection
Environment Act 1995; and
Act
1990
and
(d) Wildlife and Countryside Act 1981.
(iv) It should be noted that the requirements of the
Environment Agency or SEPA for temporary and/or
permanent Works could have implications for the
programme.
1. Written notification shall be provided 14 days in
advance of any intention to start any part of the Works
affecting a watercourse, canal, lake, reservoir, borehole,
aquifer or catchment area.
2. Watercourses including land and/or road drainage
within the Site shall be maintained in effective working
condition at all times.
3. All practicable measures shall be taken to prevent the
deposition of silt or other material in, and the pollution of,
or damage to, any existing watercourse, canal, lake,
reservoir, borehole, aquifer or catchment area arising
from operations and acts of vandalism.
4. Unless otherwise specified, approval shall be obtained
for all temporary discharges, crossings or diversions to
watercourses from the appropriate Environment
Regulator or River Authority and the work shall comply in
all respects with their requirements.
(vi) Useful guidance can also be found in the following
documents, CIRIA C650 handbook ‘Environmental
Good Practice on Site’ and CIRIA C649 and C648
CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
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‘Control of Water Pollution from Linear Construction
Projects’.
(vii) The Environment Agency, SEPA and NIEA
provide advice to industry and the public on their legal
responsibilities and good environmental practice.
5. Any construction equipment and vehicles which present
a risk of affecting a watercourse shall be removed from
Site.
(www.gov.uk/government/organisations/environmentagency).
Yorkshire Water Services Ltd additional, new or
substitute clauses.
1.15.6 (A)
The Contractor shall ensure that any
containers
of
potentially
polluting
substances are leak-proof and kept in a
safe and secure building or compound
from which they cannot leak, spill or be
open to vandalism, protected by temporary
impermeable bunds with a capacity of
110% of the maximum stored volume.
Areas for transfer of potentially polluting
substances shall be similarly protected.
Stores should be kept a minimum of 10m
from surface water drains or watercourses.
1.15.7 (A)
Only Equipment and vehicles free of all
oil/fuel leaks will be permitted on Site.
1.15.8 (A)
The Contractor shall obtain all requisite
permits, licences, consents and approvals
prior to commencing work.
1.15.9 (A)
Water containing solids, iron, manganese
or high levels of chlorine, PAH, or high
levels of pH or any other contaminant shall
be either treated before discharge, piped to
foul sewer or tankered to a suitable
disposal point – subject to permission.
1.15.10 (A)
The Contactor shall comply with the
Employers Guidance for applying for an
environmental permit and the Procedure
for Contractors Discharging to the
Employer’s Assets.
Change to any
consents, permits or licenses must be
agreed with the Employer.
1.16 WATER SUPPLY HYGIENE
(i) The use of the term “pathogenic organism test” has
been avoided since other tests will be involved.
(ii) If any particular requirements or local provisions
apply to any requirements in connection with Clause
1.16.4, then these should be detailed in the Contract.
(iii) Areas of the Works which are defined Areas of
Restricted Operations should be detailed in the
Contract.
(iv) Particular water supply hygiene requirements of
the Client may be included in the Contract.
1. All Works relating to the installation of water mains
and/or services shall be carried out in accordance with the
Water Undertaker’s Drinking Water Hygiene Code and
Water UK’s ‘Principles of Water Supply Hygiene and
Technical Guidance Notes (www.water.org.uk).
2. Any person engaged in work which is defined by Water
UK’s ‘Principles of Water Supply Hygiene: Technical
Guidance Notes’ as “Restricted Operations” shall be
registered by the National Water Hygiene Scheme
administered
by
Energy
and
Utility
Skills
(www.eusr.co.uk) and carry a National Water Hygiene
Card.
3. Any person engaged in work which is defined by Water
UK’s ‘Principles of Water Supply Hygiene: Technical
Guidance Notes’ as a “Restricted Area” shall be informed
of the need for personal hygiene and risk of
contamination, and be issued with the Water Undertaker’s
Drinking Water Hygiene Code.
CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
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4. As required by the Water Undertaker’s Drinking Water
Hygiene Code, written notification shall be provided to the
Water Undertaker of personnel working on “Restricted
Operations” who develop symptoms of certain infectious
diseases.
1.17 APPARATUS OF STATUTORY UNDERTAKERS,
HIGHWAY OR ROADS AUTHORITY AND OTHERS
(i) The Contract may indicate what is believed to be
the details of the apparatus of Statutory Undertakers,
Highway or Roads Authorities and others close to the
Works. If these details are indicated then no warranty
is given as to the accuracy or completeness of this
information.
(ii) Water UK and British Gas (currently Transco) have
agreed a ‘Model Consultative Procedure for Pipeline
Construction Involving Deep Excavation', published in
1993.
(iii) The information given under Clause 1.17.1 would
not normally include connections to and from
premises and street furniture.
(iv) Responsibility for carrying out diversion or removal
of apparatus should be detailed in the Contract.
(v) Any requirements of Statutory Undertakers or
public bodies should be described in the Contract,
together with contact names, locations, telephone and
fax numbers.
1. Before designing (where relevant) or commencing any
excavations, liaison with all relevant Statutory
Undertakers, the Highway or Roads Authority and other
owners of apparatus shall take place to ensure
satisfaction as to the exact position of existing apparatus
which may affect, or be affected by, the construction of the
Works.
2. Written notification shall be provided in advance of any
diversion or removal of apparatus which may be required
for convenience or because of the proposed method of
working.
3. A drawing of all services and apparatus encountered
shall be provided to the Client. It shall highlight any
differences with the information provided by the Statutory
Undertaker and Highway or Roads Authority.
4. The HSE Guidance Notes, Statutory Undertakers and
private company requirements shall be fully complied with
when working in the vicinity of their apparatus.
(vi) For Works likely to affect other apparatus in a
street or road see the New Roads and Street Works
Act 1991, or the Street Works (Northern Ireland) Order
1995.
Yorkshire Water Services Ltd additional, new or
substitute clauses.
CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
1.17.5 (A)
Apparatus information (if supplied by the
Statutory Undertakers, Highway or Roads
Authority) is available for inspection.
1.17.6 (A)
The Contractor shall comply fully with HSE
Guidance Note HSG 47 ‘Avoiding Danger
from Underground Services’ and HSE
Guidance Note General Series 6 (4th
Edition) GS6 - ‘Avoidance of Danger from
Overhead Electric Lines’.
1.17.7 (A)
Any excavation within 1m of the
Employer’s aqueducts shall be carried out
under the inspection of the Employer’s
staff. Seven days’ notice will be required as
will a Permit to Work.
1.17.8 (A)
The Contractor shall interrogate systems to
identify the location of high pressure
pipelines in the vicinity of the works. The
Contractor shall contact the pipeline owner
and make all necessary arrangements to
obtain access to the water network, prior to
work commencing.
1.17.9 (A)
Prior to breaking into an assumed water
main the Contractor shall tap the main to
ensure that it is in fact a water main. This
shall be done with the main still live and
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proof shall be the evidence of clean
pressurised water coming from the ferrule.
CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
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Section 1 - General
1.18 TRAFFIC REQUIREMENTS
(i) Chapter 8 of the ‘Traffic Signs Manual’ covers many
aspects which are sometimes found in Specifications,
such as traffic signals and signs, one-way working and
minimum carriageway widths.
(ii) The Contract should state who is responsible for:
(a) road closures;
(b) road diversions;
(c) New Roads and Street Works Act notices;
(d) temporary traffic control measures - including
noticeboards; and
(e) any local New Roads and Street Works Act
requirements.
(iii) For general requirements relating to road closures
and diversions, see Paragraph 8.53 of Chapter 8 of
the ‘Traffic Signs Manual’.
(iv) Arrangements made with the Highway or Roads
and Police Authorities may include provisions for
essential users, such as buses and refuse collection.
(v) Consultation and coordination with the Highway
Authority may require specific timescales for planning
and coordination. Details should be provided in the
Contract.
(vi) Direction 34(1)(b) of the ‘Traffic Signs Regulations
and General Directions 1994 No. 1519’ and the
’Specification for Portable Traffic Signal Control
Equipment for use at Roadworks TR 2502’ should be
referred to.
1. There shall be full compliance with the Code of Practice
‘Safety at Street Works and Road Works’ issued by the
Secretaries of State for Transport, Scotland and Wales
under Sections 65 and 124 of the New Roads and Street
Works Act 1991 as amended by the Traffic Management
Act 2004, and the Department of Environment (Northern
Ireland) under Article 25 of the Street Works (Northern
Ireland) Order 1995. Additionally, there shall be full
compliance with the relevant provisions of the Traffic
Safety Measures for Road Works, as contained in
Chapter
8
of
the
‘Traffic
Signs
Manual’
(http://www.dft.gov.uk/).
2. Before any work in, or affecting the use of, any highway
or road is commenced, the proposed method of working,
including any special traffic requirements, shall be agreed
with, and confirmed in writing to, the Client, the Highway
or Roads and Police Authorities.
3. All construction concerning Works in, or access to, the
highway or road shall be carried out in co-operation with
the Highway or Roads and Police Authorities.
4. Where the diversion or closure of any existing
carriageway, footway or public right of way is temporarily
necessitated by the Works, then an alternative shall be
provided and maintained which shall be operational
before any interference with the existing way takes place.
5. Where ramps are required, they shall be provided and
maintained to a standard suitable in all respects for the
class or classes of traffic or pedestrians requiring to use
them.
6. All reasonable steps shall be taken to prevent vehicles
entering and leaving the Site depositing mud or other
debris on the surface of adjacent roads or footways, and
any materials so deposited shall be removed
expeditiously.
7. An up-to-date list of supervisors and operatives who
have achieved accreditation in the relevant activities
specified in the New Roads and Street Works Act 1991 as
amended by the Traffic Management Act 2004 or the
Street Works (Northern Ireland) Order 1995 shall be
maintained on Site.
8. Emergency vehicle access to all properties shall be
maintained at all times.
9. The Works shall be planned and executed to ensure
that all relevant notices are submitted within the required
times, and such that relevant coordination activities with
the Highway Authority can be carried out.
10. Where restricted working hours apply, all excavations
in the section of highway to which the restriction applies
shall be backfilled and reinstated to an interim standard or
covered with a road plate where the Highway Authority
permits.
11. Applications shall be submitted to the appropriate
Highway Authority for approval to use portable traffic
signal equipment, as necessary, on each occasion.
Yorkshire Water Services Ltd additional, new or
substitute clauses.
CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
1.18.5 (S)
Page 27 of 192
Where ramps or temporary diversions are
required, they shall be provided and
maintained to a standard suitable in all
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Section 1 - General
respects for the class or classes of traffic
or pedestrians requiring to use them.
Yorkshire Water Services Ltd additional, new or
substitute clauses.
1.18.12 (A)
The Contractor is responsible for
organising
“Specialist
Traffic
Management” contractors, as required.
1.18.13 (A)
The Contractor shall, during the planning
and execution of the Works, regularly
assess and minimise the impact of portable
traffic signals on traffic and pedestrian
movements. This shall include, but is not
limited to:
1
Planning operations to run
sequentially and immediately after
each other:
2
Work duration planning and
monitoring to ensure that the time of
deployment is minimised:
3
Manual operation of the traffic light
sequencing during peak traffic flow
periods and where there is evidence
of traffic congestion:
4
Removal of portable traffic lights
during peak traffic flow periods.
1.18.14 (A)
The Contractor shall undertake a traffic
and
pedestrian
movement
impact
assessment before work commences and
take any necessary actions to ensure the
expeditious movement of traffic and
pedestrians during the Works.
1.18.15 (A)
The Contractor shall comply with the
following:
(i)
TR2502 ‘Specification for Portable
Traffic Signal Control Equipment for
use at Roadworks’.
(ii) TAL 02/11 ‘Portable Traffic Signals for
the Control of Vehicular Traffic’.
CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
1.18.16 (A)
The Contractor shall comply with the Street
Authority’s requirements with regard to
being informed of the use of traffic lights.
These will in general be by the use of a
form sent to the Street Authority prior to
works commencing. In the event of an
emergency use of traffic lights the Street
Authority shall be informed by telephone
followed up by a completed form.
1.18.17 (A)
All invoices and notices relating to
NRSWA/TMA fines and charges will be
received by the Employer, recorded and
issued to the Contractor upon receipt for
comment.
1.18.18 (A)
The Contractor must respond to the
Employer within ten working days
providing evidence to support any
challenges to the proposed fines and
charges.
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Section 1 - General
1.18.19 (A)
Challenges to proposed charges shall be
reviewed by the Employer and pursued
with the relevant Highway Authority if
deemed to be justified (if necessary using
the YHAUC Conciliation and Arbitration
Process).
1.19 EMERGENCY ARRANGEMENTS
(i) The Contract should indicate the responsibility for
Site security.
1. Arrangements shall be maintained whereby labour,
materials and equipment can quickly be called out,
outside normal working hours, to carry out any work
needed for an emergency associated with the Works. An
up-to-date list of addresses and telephone numbers of the
staff who are currently responsible for organising
emergency work shall be maintained.
2. Employees shall be made aware of any relevant
arrangements, including those of the Client, which are in
existence for dealing with emergencies.
Yorkshire Water Services Ltd additional, new or
substitute clauses.
1.19.3 (A)
The Contractor shall identify appropriately
qualified staff at management level, who
will take part in a formal rota to manage
and co-ordinate any developing situation
which may otherwise result in large scale
Customer disruption, or to assist The
Employer in the minimisation of the effects
of a significant incident. Standby rota
details and subsequent updates must be
made available to the Employer.
1.19.4 (A)
The Contractor must fully acquaint himself
with The Employer's Incident Management
Policy and plan (a copy of which is
available for inspection by arrangement
with the Employer) to understand the
escalation process, command and control
structure and any local arrangements
regarding emergencies and ensure that
personnel under his charge are also
acquainted with them. .
1.19.5 (A)
The Employer’s Regional Operations
Control Centre will provide a 24 hour
watching brief on operational activities with
regard to emergency matters.
1.19.6 (A)
All
personnel
involved
in
the
incident/emergency situation shall keep
their own log of actions and events. The
Contractor shall collate information for the
purpose of forming a report, which shall be
submitted to the Employer prior to the
formal de-briefing session. The Contractor
shall provide the Employer’s Control
Centre with status reports on request
1.19.7 (A)
Where necessary the Contractor shall
inform his insurance manager immediately
of details of the incident and the
Contractor’s insurance manager shall
attend the Site as soon as possible.
1.20 HAZARDOUS SUBSTANCES
(i) The following Statutory and other provisions are
also relevant:
CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
1. Hazardous substances shall not be brought onto the
Site, used for any purposes or incorporated into the Works
without the prior written consent of the Site owner, unless
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Section 1 - General
specified in the Contract. All necessary licences shall be
obtained.
• The Control of Explosives Regulations 2014
• Petroleum (Consolidation) Regulations 2014
2. The location of each explosives magazine and store of
any other hazardous substance on the Site shall be
approved in writing.
• The Dangerous Substances and Explosive
Atmospheres Regulations 2002 and The Dangerous
Substances and Explosive Atmospheres Regulations
(Northern Ireland) 2003;
• Control of substances
regulations 2002
3. The storage of blasting explosives shall be in
accordance with the conditions (if any) of the Statutory
licence obtained and the relevant provisions of BS 5607.
hazardous to health
• The Planning (Hazardous Substances) Regulations
1992 (as amended for England, Scotland and
Northern Ireland);
• The Planning (Control of Major-Accident Hazards)
Regulations 1999, the Planning (Control of MajorAccident Hazards) Regulations (Northern Ireland)
2000, the Planning (Control of Major-Accident
Hazards) Regulations (Scotland) 2009; and
• The Control of Pollution (Oil Storage) (England)
Regulations 2001 and the Control of Pollution (Oil
Storage) (Northern Ireland) Regulations 2010.
Yorkshire Water Services Ltd additional, new or
substitute clauses.
1.20.4 (A)
Where the Contract requires the handling
or use of bulk chemicals such as chlorine
or sulphur dioxide or work to be carried out
on, or immediately adjacent to, any existing
or proposed bulk chemical installation, the
Contractor shall comply with the
appropriate safety regulations:
‘Dangerous Substances and Explosive
Atmospheres Regulations’ 2002.
1.20.5 (A)
All petroleum and inflammable materials
shall be stored in fireproof buildings. No
petroleum spirit within the meaning of the
Petroleum (Consolidation) Regulations
2014 shall be stored on the Site until the
necessary licences under the regulations
have been obtained.
1.20.6 (A)
Safety data sheets must be provided for all
hazardous materials brought onto site
together with COSHH assessments
detailing usage and storage arrangements.
1.21 ENVIRONMENT AND SUSTAINABILITY
1. Design and construction of the Works shall be carried
out in accordance with any environmental mitigation
measures specified in the Contract.
2. All Site operations shall be managed to minimise waste
of construction materials and maximise the recycling of
waste.
3. The Contractor shall make his Site staff and contractors
fully aware of any specific environmental practices
relevant to the Site, including the process for reporting
environmental incidents specified in the Contract.
CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
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Section 1 - General
1.22 CUSTOMER CARE
(i) Copies of the Client's policy should be included in
the Contract.
1. All construction operations shall be carried out with due
regard for the customer care policy specified in the
Contract.
Yorkshire Water Services Ltd additional, new or
substitute clauses.
1.22.1 (S)
The Contractor shall comply with the
Employer’s Customer Charter.
1.23 ASSET RECORDS
(i) Details of the Client's requirements should be
included in the Contract.
1. As-built records of all Works constructed, and existing
services encountered during the construction of the
Works, shall be submitted in accordance with the Contract
Yorkshire Water Services Ltd additional, new or
substitute clauses.
1.23.1 (S)
As-built records of all Works constructed,
and existing services encountered during
the construction of the Works, shall be
submitted in accordance with the
Engineering Specification Section 9.
1.24 TRAINING
(i) Details of the Client's requirements should be
included in the Contract.
CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
1. The Client’s staff, or appointed representatives, shall
be trained in the operational and maintenance
requirements for any new installation. This training shall
be provided just prior to take over and at times to suit the
Client’s staff availability.
Page 31 of 192
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Section 1 - General
Yorkshire Water Services Ltd additional, new or
substitute clauses.
CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
1.24.2 (A)
The Contractor must be able to
demonstrate from the beginning of the
contract and maintain at all times and in all
circumstances training and the deployment
of resources structured such that each and
every individual is trained to adequate
standards, formally certified where
appropriate, and are competent in all tasks,
existing and new techniques and
workmanship in all areas of work being
undertaken.
1.24.3 (A)
For works in potable water and water and
sewerage assets, the Contractor shall
establish and maintain detailed individual
employee training and competency profiles
in the form of a “skills library”. The library
shall cover all skills, competencies and
training undertaken and required to
undertake the tasks assigned to a
particular individual. The Contractor shall
also establish and maintain an individuals
“Passport to Work” or equivalent booklet
containing skills, competencies and
training achieved, the date they were
achieved and the accrediting body which
issued them. The records shall incorporate
any statutory training requirements. The
Employer, will from time to time, audit both
the Skills Library and Passport to Work
systems and documents.
1.24.4 (A)
The Contractor shall establish and
maintain
an
individual
employee
development / training plan to ensure that
the individuals potential is maximized.
1.24.5 (A)
Where Services are provided for
Developers for supply of potable water on
their sites, the Contractor will be required
to be either accredited, or be working
towards being accredited, through the
Water Industry Registration Scheme
(WIRS) operated by Lloyd’s Register for
the undertaking of Water Mains and
Service Laying Services on Development
sites.
1.24.6 (A)
The Contractor shall demonstrate through
the term of the contract that a
comprehensive program of Tool Box Talk,
or equivalent, training is in place. The
program shall cover all aspects of the
services, including but not limited to, health
and safety, customer care, protecting the
public from harm, operational best
practice, resource and waste management
and ‘hot topics’.
1.24.7 (A)
Where
contractors
need
to
interact/interface with customers / their
property the Contractor shall demonstrate
individual interpersonal skills in ‘customer
care’, the ability to deal with all types of
customers, including how to interact with
customer and managing difficult situations.
Evidence that staff have completed the
training to a suitable level shall be
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Yorkshire Water Engineering Specification
Section 1 - General
presented to the Employer as part of the
Contractor’s training records.
The
Contractor shall, or working towards being,
a member of the Institute of Customer
Services. The Contractor’s staff, as a
undertake
First
basic
minimum,
Impressions training.
CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
1.24.8 (A)
For Distribution and Sewerage Assets
only. The Contractor shall appoint, for the
duration of the Contract or as otherwise
agreed by the Employer, ‘Coaches’ whose
role will be to provide support to
administration and operational employees.
Each coach should have adequate
qualifications and be able to demonstrate
skills
which
drive
“Coaching
for
Excellence”.
1.24.9 (A)
The Contractor shall ensure that all
relevant personnel engaged on the
Contract are fully conversant with the
requirements of street works legislation
and they shall be fully trained and
accredited for the role an individual is
undertaking. The Contractor shall furnish
the Employer and keep up to date records
of all personnel engaged in street work
activities that indicate their NRSWA/TMA
accreditation details. Site operatives shall
carry
their
NRSWA
accreditation
documentation and make available for
inspection by either the Employer or Street
Authority. Planning staff will be required to
undergone
and
successfully
have
completed a street works administration
course which will qualify them to operate
under a Noticing and Permit Scheme.
1.24.10 (A)
Supervisors / Site Managers / Agents shall
be adequately trained, qualified and
experienced as agreed by the Employer.
1.24.11 (A)
The Contractor shall appoint a competent
safety supervisor to ensure that adequate
safety training, inspections and reporting is
carried out.
1.24.12 (A)
The Contractor shall ensure that sufficient
numbers of resources are trained in
Emergency First Aid. During the first year
of the contract, the Contractor shall ensure
that 100% of its operational resource is
trained to this standard.
1.24.13 (A)
The Contractor shall ensure that during the
first year of the contract all operational
resources have received training in manual
handling.
1.24.14 (A)
Before the undertaking of activities the
Contractor shall ensure that new starters
training and accreditation is checked and
verified. Training and accreditation shall
be entered onto the Contractor’s skills
register.
1.24.15 (A)
The Contractor shall ensure that staff
responding or making Customer calls have
been adequately trained in telephone
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Section 1 - General
conversation
demonstrate
behaviors.
skills and are able to
caring and responsive
Yorkshire Water Services Ltd additional, new or
substitute clauses
1.28 (N)
PERMANENT SIGNAGE
1.28.1
Permanent signs shall be in accordance
with the Employer’s Identity Guidelines.
Further details can be obtained from YWS
Communications.
Yorkshire Water Services Ltd additional, new or
substitute clauses
1.29 (N)
ALTERNATIVE / CONTINOUS SUPPLIES
1.29.1
The Contractor shall provide and erect as
required by the Employer, such temporary
by-pass pipe work of a type and condition
suitable for the conveyance of pressurised
water, necessary to provide the continuity
of service.
1.29.2
Any by-pass arrangements shall
designed to deal with existing flows.
1.29.3
All by-pass pipe must be restrained as
necessary and adequately signed and lit
for protection of pedestrians and road
users. Ramps shall be provided at point of
public access.
1.29.4
As a minimum where the planned
interruption to supply is expected to last 5
hours or more, or where two or more
interruptions to supply (in any 48 hour
period) when aggregated are expected to
last 5 hours or more, the Contractor shall
make an alternative water supply available
to affected customers either by bowsers
appropriately located in the area or by
bottled water delivered to customers’
properties.
1.29.5
The Contractor shall provide bottled water
to known special needs customers if
instructed to do so irrespective of the
length of interruption to supply.
1.30 (N)
SUPPLY OF WATER
1.30.1
The Contractor shall only use approved
stand-pipes issued by the Employer under
license and only draw water from the
Employer’s distribution network from
designated points. The Contractor shall be
required to pay for each licensed standpipe.
1.31 (N)
HAUC
HIGHWAYS
AUTHORITIES
UTILITIES COMMITTEE CODE OF
CONDUCT
1.31.1
The Contractor will adhere to the latest
version of the HAUC ‘Highways Authorities
Utilities Committee’ code of conduct.
CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
Page 34 of 192
be
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Section 2 - Materials
SECTION 2
MATERIALS
The Notes for Guidance are not part of
the Specification.
(i) The use, installation, application or
fixing of materials and components
should be in accordance with the
manufacturer’s recommendations.
2.1 MATERIALS IN CONTACT WITH POTABLE WATER
(i) Where possible, all fittings used as
part of the supply of treated water for
domestic purposes in premises should
be approved by WRAS.
(ii) See the ‘Principles of Water Supply
Hygiene: Technical Guidance Notes’
published
by
Water
UK
(www.water.org.uk).
(iii) When planning, designing and
constructing water mains and/or
services in brownfield sites, reference
should be made to the UKWIR
document “Guidance for the Selection
of Water Supply Pipes to be used in
Brownfield Sites”.
Yorkshire
Water
Services
Ltd
additional, new or substitute clauses.
1. All materials, substances and products in contact with potable water shall
comply in all respects, for England, with the Water Supply (Water Quality)
Regulations; for Scotland, with the Water Supply (Water Quality) (Scotland)
Regulations; for Northern Ireland, with the Water Supply (Water Quality)
Regulations (Northern Ireland); and for Wales, with the Water Supply (Water
Quality) Regulations (Wales).
2. Where a European Standard (EN) exists in respect of any chemicals used
in connection with the preparation or conveyance of public water supplies, the
provisions shall be complied with.
2.1.1 (S)
The Contractor shall supply only substances and products that
comply with the requirements of Regulation 31 of The Water
Supply (Water Quality) Regulations 2000 (as amended) for use
in circumstances where the substance or product will be or
could be in contact with water under preparation or
conveyance for public water supply.
The Employer’s normal minimum requirements for substance
or product approval in accordance with Regulation 31 vary with
the extent of contact, or possible contact.
For interpretation of the extent of trivial/low or high contact,
guidance is available from the Employer’s Quality Regulation
Department and examples are as listed in the Guidance Notes
for the Engineering Specification and Particular Specification
in Clause 2.0. Examples shown are as cited in Advice Sheet
8 – “Products permitted to be used under Regulation 31 (4)(b)
For trivial/low contact situations, the Committee on Products
and Processes (CPP) advises that water companies may use
unapproved products if the water company is satisfied that the
product “is unlikely to affect adversely the quality of the water
supplied”. Although approval is not required for the products
listed in Annex 1, the Drinking Water Inspectorate (DWI) has
advised that non-metallic products should conform to the test
requirements of BS6920:2000 or an equivalent European
technical specification. Products that conform to these
requirements are listed in the Water Fittings and Materials
Directory, published bi-annually by the WRAS.
For high contact situations, approval in accordance with 2(N)
(i) below is required or in exceptional circumstances the
Employer may use a specific product or substance in
accordance with 2(N) (ii).
CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
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Section 2 - Materials
The Contractor shall:
(i)
Produce documentary evidence that the substance or
product has been specifically approved for purpose under
regulation 31(4a), or
(ii) Obtain written approval from the Employer prior to use of
the substance in the Works.
Yorkshire
Water
Services
Ltd
additional, new or substitute clauses.
2.1.3 (A)
The alternative approvals for a substance or product in
accordance with Regulation 31 for use in the works are:
(i) that it has been specifically approved by the Secretary of
State under Regulation 31 of The Water Supply (Water
Quality) Regulations 2000 for the type of use proposed;
(ii) that the substance or product is to be applied or introduced
solely for the purposes of testing or research, and the
water undertaker has given notice to the Secretary of State
not less than 3 months’ notice in writing of its intention so
to apply or introduce the substance or product.
2.1.4 (A)
The Contractor shall identify and list in a schedule in the
Particular Specification every substance and product that is to
be supplied under the Contract and which will be or could be
in contact with water under preparation or conveyance for
public water supply. The Contractor shall identify in the
schedule whether the extent of contact is trivial, low or high (in
accordance with DWI guidance) and how the substance or
product complies with the Regulations.
Copies of the schedule shall be submitted to and approved by
the Employer prior to commencement of Site operations.
The Contractor shall maintain the required schedule
throughout the Contract such that it is always an accurate
record of materials that have been supplied or are proposed
for supply, for use in the works. Where required by conditions
of use, Site Logs shall be kept of curing conditions
(temperature, cure time and whether cured according to cure
curves.).
2.1.5 (A)
No substance or product may be used in the works which will
be or could be in contact with water under preparation or
conveyance for public water supply if its use has been
prohibited, or approval under Regulation 31 has been refused,
by the Secretary of State.
2.1.6 (A)
All sampling and testing of materials for compliance shall be
performed when requested.
2.1.7 (A)
In using the approved substances and products the Contractor
shall strictly comply with any Conditions of Approval issued by
the Secretary State together with the Manufacturer’s
Instructions.
2.1.8 (A)
All fittings shall comply with the Water Supply (Water Fittings)
Regulations 1999. Products that conform to these
requirements currently carrying approval are published in
Section 1 on the Water Regulations Advisory Scheme (WRAS)
‘Directory of Fittings, Materials and Appliances’ for use on the
UK Water Supply System. The Water Regulations Advisory
Scheme (WRAS) ‘Directory of Fittings, Materials and
Appliances’ is published on the WRAS website
(http://www.wras.co.uk/directory).
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Section 2 - Materials
2.2 ACRYLONITRILE-BUTADIENE-STYRENE (ABS) PIPES AND FITTINGS
1. Acrylonitrile-butadiene-styrene (ABS) pressure pipes and fittings shall
comply with the relevant provisions of BS 5391-1 and BS 5392-1,
respectively.
2.3 ADMIXTURES FOR CONCRETE OR GROUT
(i) Clause 5.2.1 of BS EN 206-1
prohibits the use of air-entraining
admixtures in standardised prescribed
concrete. BS 8500-2 restricts the use of
admixtures in designated concrete.
1. Admixtures for use in concrete or grout shall comply with the relevant
provisions of BS EN 934-2.
2. Admixtures containing chlorides shall not be used in reinforced concrete
designed to retain an aqueous liquid.
(ii) The use of accelerators, water
retaining agents, etc., is not good
practice in bedding to manhole covers.
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additional, new or substitute clauses.
2.3.3 (A)
Admixtures shall not be used for potable water systems without
prior approval. A request for approval shall be accompanied
by the manufacturers' full technical specification. When in
contact with potable or raw water, only those components
listed in Appendix 2.4 of current Drinking Water Inspectorate
list of approved products and processes (List of Authorised
Cement Admixtures) are acceptable. Their approval for use is
subject to compliance with the manufacturer’s recommended
dose. Records of use must be retained for inspection.
2.4 AGGREGATES FOR CONCRETE
(i) Any restrictions on the source, type
or group classification of aggregates
should be described in the Contract.
1. Aggregates for concrete shall comply with the relevant provisions of the
appropriate Standard, as set out below:
Type of
Aggregate
(ii) Concrete designed to retain an
aqueous liquid should be described as
such in the Contract.
Natural
aggregates
Air-cooled
blastfurnace
slag
aggregate and
other
manufactured,
normal weight
aggregate
(iii) Aggregates should also comply with
the requirements of Clause 4.3 of BS
8500-2:2006.
iv) For the limitation of total chloride ion
content of the concrete mix see Clause
2.25.British Standards no longer contain
specific chloride limits for aggregates.
Designated
Designed
Standardised
Prescribed
BS EN
12620 and
PD 6682-1
BS EN
12620 and
PD 6682-1
BS EN 12620
and PD 66821
Lightweight
aggregates
Prescribed
BS EN
12620 and
PD 6682-1
BS EN
13055-1
and PD
6682-4
BS EN
13055-1
and PD
6682-4
Coarse,
recycled
concrete
aggregate
BS 8500-2
BS 8500-2
BS 8500-2
Coarse,
recycled
aggregates
BS 8500-2
BS 8500-2
BS 8500-2
2. The water absorption of aggregates for concrete designed to retain an
aqueous liquid shall not exceed 3% when measured in accordance with
BS EN 1097-6.
3. The proportion of coarse, recycled aggregate and coarse, recycled
concrete aggregate shall not exceed 20% by mass of the total coarse
aggregate in concrete. Fine, recycled aggregate or fine, recycled concrete
aggregate shall not be used in concrete.
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4. Recycled aggregates and recycled, concrete aggregates shall only be
used in contact with raw or potable water where it is has been
demonstrated that they are suitable for this application.
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2.4.5 (A)
The use of ‘all-in’ aggregates shall not be permitted.
2.5 AGGREGATES FOR HIGH STRENGTH CONCRETE WEARING
SCREEDS
1. Aggregates for high strength concrete wearing screeds (granolithic
finish) shall comply with BS EN 12620 and PD 6682-1, and be 10 mm
nominal size, graded in accordance with Table E.1 of PD 6682-1:2009
and shall have a Los Angeles Coefficient of no greater than 30.
2.6 AGGREGATES FOR MORTAR
1. Fine aggregates for mortar shall be washed natural sand or crushed
natural stone and shall comply with BS EN 13139 and PD 6682-3.
2.7 ASPHALT CONCRETE
1. Asphalt concrete and porous asphalt for roads and other paved
surfaces shall comply with the relevant provisions of BS EN 13108-1 and
BS EN 13108-7, respectively.
2. The binder shall be bitumen containing no cut back agent.
3. Wearing course shall have an aggregate abrasion value (AAV) of 16
and a minimum polished stone value (PSV) of 50. Limestone aggregate
shall not be used in a wearing course.
2.8 BIOLOGICAL PERCOLATING FILTER MEDIA
(i) The type of media and its nominal
size and grading should be described in
the Contract.
(ii) Appendix E6 of BS 1438:2004 gives
recommendations for the placing of
filter media.
(iii) An additional specification will be
required for a filter media other than
those covered by BS 1438.
1. Media for use in biological percolating filters from natural sources or
derived from the reduction of iron ore in a blast furnace, shall comply with
the relevant provisions of BS 1438. All media for filter beds shall be
washed, graded and screened.
2. Grading of crushed rock (e.g., granite) or blast furnace slag filter media
shall be either 75-40 mm or 63-40 mm. A further screening at 20 mm mesh
size shall be undertaken on Site as the media is placed. Material passing
through this screen shall not be used.
3. Structured modular crossflow media (PVC or polypropylene) products
shall be specifically designed for wastewater treatment. Media assembled
from sheets where the edges have been heat flanged shall not be used.
4. The media product shall be designed in such a way that it is:
(a) resistant to degradation from rot, fungi, and other forms of attack;
(b) chemically resistant to normal sewage, normally
concentrations of acids, alkalis and organic compounds;
expected
(c) self-extinguishing and compounded to be totally stable under the
action of UV light.
5. Media modules shall be designed to:
(a) be 100% crossflow media with no vertical or horizontal corrugations;
(b) have a specific surface area of 150 m2/m3 with 25,000 mixing points
per cubic metre as a minimum and with a minimum 97% void to volume
ratio;
(c) provide a minimum of 70% open area at the pack to pack interface.
Horizontal surfaces shall not exceed a width of 2 mm. The media shall not
allow a drop of water to free fall more than 150 mm;
(d) be capable of redistributing wastewater horizontally a minimum of
300mm per 300 mm of media depth;
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Section 2 - Materials
(e) allow the media to be structurally self-supporting with a minimum
bearing capacity of 1.5 kN/m2.
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additional, new or substitute clauses.
2.8.1 (S)
Mineral media for use in new biological percolating filters
shall be sourced from the reduction of iron ore in a blast
furnace, and shall comply with the relevant provisions of
BS 1438 and shall be washed, graded and screened.
2.8.2 (S)
Grading of crushed rock (e.g., granite) or blast furnace slag
filter media shall be as set out in the YW Mineral Media
Filter Asset Standard. A further screening at 20 mm mesh
size shall be undertaken on site as the media is placed.
Material passing through this screen shall not be used.
2.8.3 (S)
Plastic media for use in new biological plastic percolating
filters shall be structured modular cross flow media (PVC
or polypropylene. Random plastic filter media shall not be
used.
2.8.4 (S)
For tertiary nitrification applications, the specific surface
area of the structured media shall be a minimum of 190
m2/m3.
2.8.5 (S)
Refer to YWS Plastic Media Filter Asset Standard for
additional design details.
2.8.6 (S)
Refer to YWS Plastic Media Filter Asset Standard for
additional design details.
2.9 BITUMEN ROAD EMULSIONS
1. Bitumen road emulsions shall comply with the relevant provisions of BS
434-1.
2.10 BITUMINOUS COATINGS
1. Bituminous coatings shall comply with BS 3416.
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additional, new or substitute clauses.
2.10.2 (A)
The final coating for all previously uncoated ferrous pipe
and fittings surfaces where compliance with Clause 2.1 is
not required shall be a thixotropic mineral filled bitumen
based barrier coating containing hard natural bitumen. The
coating shall be black with resistance to degradation from
UV light improved by inclusion of mica in the formulation.
The volume of solids –shall be approximately 43% with a
covering capacity of 3-4 sq.m/litre. Application shall be by
brush, roller or airless spray.
2.11 BITUMINOUS JOINTING STRIP
1. Jointing strip for precast concrete tunnel and shaft segments shall be
bitumen based, 3 mm minimum thickness and be suitable for the size and
type of segments with which it is to be used. Where bolt holes are
required, they shall accurately match, in size and position, the
corresponding holes in the segments.
2.12 BOARDS FOR PANELLING
(i) The required type, grade and
thickness of board should be described
in the Contract.
1. Boards for panelling shall comply with the relevant provisions of the
appropriate Standard, as set out in the following table:
(ii) Rigid urethane foam boards should
be CFC free.
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Section 2 - Materials
Board Type
Standard
Fibre building board – hard board
Fibre building board – medium board
Fibre building board – soft board
Fibre building board – MDF
BS EN 622-1 and -2
BS EN 622-1 and -3
BS EN 622-1 and -4
BS EN 622-1 and -5
Gypsum plasterboard
BS EN 520
Expanded polystyrene boards -expandable
beads
BS 3837-1
Expanded polystyrene boards – extruded
boards
BS EN 13164
Rigid urethane foam - laminated board for
building purposes
BS 4841-1
Rigid urethane foam - laminated board for use
as a wall and ceiling insulation
BS 4841-2
Decorated laminated plastics sheet veneered
boards and panels
BS 4965
Particleboard
BS EN 634-1 and -2
2.13 BOND BREAKING COMPOUND FOR DOWEL BARS
1. For water-retaining structures, bond breaking compound for dowel bars
shall not contain materials likely to adversely affect potable water
contained within the structure. The compound shall be constituted such
that it will perform effectively for the design life of the concrete. It shall in
no way retard or otherwise affect the setting of concrete.
2.14 BRICKS AND BLOCKS
(i) The type, class and grade of all new
and recycled bricks and blocks should
be described in the Contract.
1. Clay bricks, calcium silicate bricks and precast concrete masonry units
shall comply with the relevant provisions of BS EN 771-1, BS EN 771-2
and BS EN 771-3, respectively.
(ii) Particular requirements for air bricks
and gratings from the options listed in
Appendix A of BS 493:1995 should be
described in the Contract.
2. Bricks to be used for manholes and chambers shall be solid Class B
engineering bricks to BS EN 771-1.
(iii) Bricks used in bedding to manhole
covers should be bonded using high
strength mortar (such as polyester
resin).
3. The shapes and dimensions of special bricks shall comply with the
relevant provisions of BS 4729.
4. Air bricks and gratings for wall ventilation shall comply with the relevant
provisions of BS 493 and shall match any surrounding bricks.
5. Precast concrete blocks to be used below damp-proof courses shall
comply with Table 12 in BS 5628-3:2005.
6. All bricks shall have freeze/thaw designation F2.
7. All bricks shall have active soluble salts content designation S2.
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additional, new or substitute clauses.
2.14.8 (A)
Contractors will undertake the construction and
reinstatement of Access Chambers and Frames in the
Highway including the use of C32/40 Concrete or Solid
Class B Engineering Bricks, in accordance with the
Specification for the Reinstatement of Openings in the
Highway (SROH) including, but not exclusively, the
following sections:
S2.3 Fixed Features
S11.5 Ironwork and Apparatus
2.15 CAST STONE
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(i) The type, constituent material and
colour of cast stone should be
described in the Contract.
Section 2 - Materials
1. Cast stone shall comply with the relevant provisions of BS 1217.
2. Reconstructed stone masonry units shall comply with the relevant
provisions of BS 1217 and BS EN 771-5.
2.16 CEMENT
(i) The permitted type(s) of cement
should be described in the Contract.
1. Cement shall either:
(a) be factory-produced by the cement manufacturer and comply with the
provisions of the appropriate Standard, as set out below.
or
(b) be combinations, complying with BS 8500-1 Annex A, of CEM 1
cement conforming to BS EN 197-1 and fly ash conforming to BS EN 4501 or blast furnace slag conforming to BS EN 15167-1.
(ii) PFA (pulverised fly ash) in Portlandfly ash cement and Pozzolanic cement
and in combinations, should be siliceous
only. Pozzolana used in Portlandpozzolana cement should be metakaolin
only.
(iii) Cement for annulus grouts should
comply with either BS EN 197-1 (CEM
1, 42.5 or 52.5) or BS 4027.
Cement Type
Standard
Portland cement (CEM I)
BS EN 197-1
Portland-silica fume cement (CEM II/A-D)
BS EN 197-1
Portland-limestone cement (CEM II/A-L; CEM
II/A-LL)
BS EN 197-1
Portland-pozzolana cement (CEM II/A-Q; CEM
II/A-Q)
BS EN 197-1
Portland-slag cement (CEM II/A-S; CEM II/B-S)
BS EN 197-1
Portland-fly ash cement (CEM II/A-V; CEM II/BV)
BS EN 197-1
Blastfurnace cement (CEM III/A; CEM III/B)
BS EN 197-1 or -4
Pozzolanic cement (CEM IV/B)
BS EN 197-1
Sulphate-resisting Portland cement
BS 4027
Pozzolanic pulverised-fuel ash cement
BS 6610
Masonry cement
BS EN 413-1
2. White and coloured Portland cement shall comply with the chemical and
physical requirements of BS EN 197-1. Added pigments shall comply with BS
EN 12878 and shall be mixed with the cement in accordance with the
manufacturer’s instructions. The amount of added pigments shall not exceed
10% of cement by mass, except for carbon black where the limit shall be 2%.
3. Blast furnace slag cement for the in-situ lining of water mains shall comply
with WIS 4-13-01.
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additional, new or substitute clauses.
2.16.1 (S)
Cement shall:
(a) be manufactured by BSI registered companies of assessed
capability and comply with the provisions of the appropriate
Standard, as set out below. Manufacturers Average Daily
Test Certificates shall be obtained by the Contractor’s
Representative. The Certificates shall state alkali content.
Cement type
CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
Standards
Portland (CEM I)
BS EN 197-1
Portland-silica fume (CEM II/A-D)
BS EN 197-1
Portland-limestone (CEM II/A-L; CEM II/A-LL)
BS EN 197-1
Portland-pozzolana (CEM II/A-Q; CEM II/B-Q)
BS EN 197-1
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Section 2 - Materials
Portland-slag (CEM II/A-S; CEM II/B-S)
BS EN 197-1
Portland-fly ash (CEM II/A-V; CEM II/B-V)
BS EN 197-1
Blast furnace (CEM III/A; CEM III/B)
BS EN 197-1
Pozzolanic (CEM IV-B)
BS EN 197-1
Sulphate-resisting Portland
BS 4027 or BSEN 197-1
Blast furnace slag
BS EN 197-1
Pozzolanic pulverized-fuel ash
BS 6610
Masonry
BS EN 413-1
Or
(b) consist of a combination of Portland (CEM I) cement
complying with the relevant provisions of BS EN 197-1:2000
and ggbs or fly ash in accordance with the following, to be
included as part of the concrete mix by simultaneously
combining them with the other concrete materials at the
concrete mixer:
Use of
concrete
British Standard to
be complied with
Percentage by
mass of
cementitious
content
Ggbs
Any
BS 6699 or BS EN
15167-1
6 – 80
Fly ash
Any
Cementitious
component
other than
cement
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additional, new or substitute clauses.
2.16.4 (A)
BS EN 450-1
6 - 55
All cementitious materials shall be delivered and stored in
suitable sealed packaging or approved bulk containers.
Protection shall be made against contamination and ingress of
moisture. The storage method shall facilitate the use of the oldest
material first. Materials that appear contaminated or partially
hydrated shall not be used in the works.
2.17 CEMENT GROUTS
(i) The required class of grout, together
with the type of cement and any
admixture should be described in the
Contract.
1. Cement grout shall be mixed in the relevant proportions indicated in the
following table, using the minimum quantity of water to ensure the necessary
fluidity and to render it capable of penetrating the work.
Class
Nominal Mix by Mass
Cement
Sand
Pfa
G1
1
-
-
G2
1
3
-
G3
1
10
-
G4
1
-
10
G5
1
-
4
G6
1
-
0.5
2. Cement grout shall be used within one hour of mixing, except where
containing a grout retardant admixture.
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3. Cement for fixing inserts and below plant bases shall include an approved
expanding additive.
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CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
2.17.4 (A)
An additional class G7 thixotropic grout may be required. The
grout is a cement/PFA (fly ash) mix of minimum cement content
of 1/3 with a thixotropic additive. Specific mix details are in
accordance with the manufacturers’ instructions and are to be
varied to suit the particular circumstances encountered. (See
Table )
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Section 2 - Materials
2.17.5 (A)
The compiler should specify the grout Class, water/solids ratio
and 28 day compressive strength for the requirements of the
Particular Specification and for the testing needs in Section 4
Clause 4.26. As an alternative, the grout strength should be
quoted and the grout mix left to the discretion of the Contractor.
As an indication a neat cement grout with a water/solids ratio
of 0.45 would be expected to reach the following strengths:1 day
7 days
28 days
18 N/mm2
40 N/mm2
55 N/mm2
Typical grout strengths that depend upon the water/solids ratio
are indicated below for mixes that include fly ash.
Fly ash:
Cement
Ratio
Water/Solids
Ratio
1:1
2:1
3:1
5:1
7:1
10:1
15:1
20:1
2.17.6 (A)
Compressive Strength Development
(N/mm2)
7 days
28 days
0.40
17.9
31.7
0.45
14.0
26.0
0.50
10.3
20.0
0.40
8.7
17.5
0.45
6.2
13.2
0.50
5.4
12.1
0.40
4.5
10.4
0.45
3.3
8.3
0.50
2.7
7.2
0.40
2.2
5.1
0.45
1.6
4.4
0.50
1.4
4.0
0.40
2.2
5.5
0.45
1.6
4.6
0.50
1.4
2.9
0.40
1.5
2.3
0.45
0.8
1.9
0.50
0.7
1.8
0.40
1.0
2.3
0.45
0.6
1.7
0.50
0.6
1.2
0.40
0.7
1.5
0.45
0.5
1.4
0.50
0.5
0.8
Mixes for neat cement grout shall contain sulphate-resisting
Portland cement to BS 4027 or BS EN 197-1.
2.18 CLAY PUDDLE
1. Clay puddle shall be impervious to water and be free from sand, grit, stones
and other deleterious matter.
2. The clay on being dug shall be exposed to the air for at least 24 hours and,
thereafter, shall be worked with water into a consistency suitable for punning.
A roll of clay, 300 mm long and 40 mm in diameter, shall support its own weight
when suspended vertically from one end.
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2.19 COMPRESSIBLE FILLER AND PACKING FOR PIPELINES
1. Compressible filler for interrupting concrete protection to pipelines shall
consist of bitumen-impregnated insulating board to BS EN 622-1 and BSEN
622-4. The thickness of compressible filler shall be as follows:
Nominal Bore of Pipe (mm)
Thickness of Compressible Filler (mm)
Less than 450
18
450 – 1200
36
Exceeding 1200
54
2. Compressible packing for use between pipes and precast concrete setting
blocks shall consist of bitumen damp-proof sheeting, complying with BS 6398.
3. Bituminous materials shall not be put into contact with plastics pipes.
2.20 CONCRETE – GENERAL
(i) The characteristic compressive
strength described in the Contract should
be selected, where possible, to achieve
the required minimum cementitious
content. If the relevant information is not
available, initial testing may be required
to establish the required characteristic
strength. If aggregates to be used are too
weak to produce the characteristic
strength needed for high grade concrete,
an alternative basis of assessing the
cementitious content may be required.
(ii) Where it is important that concrete
should
attain
its
maximum
impermeability within 6 months of
placing, a maximum free water/
cementitious ratio less than 0.6 would be
required and should be described in the
Contract.
1. Concrete shall be produced, transported and accessed in accordance with
BS 8500-2.
2. The cementitious content of concrete designed to retain an aqueous liquid
shall be between 325-400 kg/m3 with a maximum free water/ cementitious
ratio of 0.55.
3. The maximum size of aggregate in any structural member shall not exceed
25% of the minimum thickness of the member.
4. Conformity control and criteria shall be undertaken in accordance with
BSEN 206-1:2013 Clause 8.
5. Where identity testing is specified as defined in BS 8500-1, Annex B for
strength, it shall be undertaken in accordance with BS EN 206-1:2013, Annex
B as follows:
Type of Structure
Sample to Represent a
Volume of (m3)
Critical structures
10
Intermediate structures
50
Heavy concrete construction
100
(iii) See Clause 2.21 for concrete mixes
containing PFA or GGBS.
(iv) Where the Contract requires
aggregates of nominal size other than 20
mm to be used, the minimum
cementitious content should be modified
in
accordance
with
BS
85001:2015+A1:2016 Table A7.
(v) Where there is the likelihood of
unacceptable damage from alkali- silica
reaction, specific precautions to minimise
it should be described in the Contract in
accordance with the recommendations of
BRE Digest 330. Guidance relating to
alkali-silica reaction is contained in BS
8500-2:2006 Section 5.2.
(vi) Examples of the type of structure in
2.20.5 are:
Critical structures:
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Section 2 - Materials
- cantilevers, columns, suspended slabs;
Intermediate structures:
- beams, ground slabs, bridge decks,
walls;
Heavy concrete construction:
- foundations, solid rafts.
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CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
2.20.6 (A) Unless otherwise described in the Contract, and except where
Designated Concrete mixes are otherwise indicated in Table
2.20 below, all concretes shall be Designed Concretes supplied
in accordance with the relevant clauses of BS 8500-1, and BS
8500-2, for the appropriate environmental conditions and
intended working life as provided in the Design Life table in
Section 03.01.
2.20.7 (A)
The Contractor shall submit his mix design proposals for
acceptance, in accordance with the Contract, at least 7 days
before the concrete is to be incorporated into the works, for
each of the types of concrete proposed for use in the works,
and as shown on the drawings or otherwise directed.
2.20.8 (A)
The Yorkshire Water Standard Mixes shown in Table 2.20
below are standard references for concrete mixes from which a
selection may be made at the design stage, as being
appropriate for the purpose and for the particular conditions
stated in the Guide Notes to Table 2.20.
2.20.9 (A)
The Designer shall give guidance to the Constructor on the
designated “type of structure” in relation to sampling rates for
identity testing in the table in Clause 2.20.5. Alternatively, the
Designer shall specify the rate of sampling in terms of the
volume of concrete or the number of truckloads.
2.20.10 (A)
BRE SD1 and BS 8500-1 provide for classification of sulphate
resistance
(including
Thaumasite)
requirements
by
specification of Design Chemical Class (DC) and, in some
cases, Additional Protective Measures (APM). The Particular
Specification shall specify the permissible options for Design
Chemical Class and Additional Protective Measures required in
accordance with SD1 and BS 8500-1. The intended working
life of the structure shall be as indicated in the Asset Design
Life table in Section 03.01.
2.20.11 (A)
CSOs and associated tanks on the sewerage system do not
need to be designed to water retaining standards.
2.20.12 (A)
Before use in the works, the Contractor shall submit full details
of the proposed chemical curing agent for approval.
2.20.13(A)
During production of designed concrete the Contractor shall
advise the Contractor’s Representative of any proposed
changes in the source or nature of any constituent materials,
and of proposed changes in concrete composition. Where,
however, the proposed change includes a reduction in the
cement content from that last approved, the Contractor shall resubmit under Clause 4.1.2(A), details of the new proposals with
supporting evidence for the change, to the Contractor’s
Representative for approval.
2.20.14 (A)
All compounds shall be pigmented to indicate effective
coverage.
2.20.15 (A)
When chemical curing agents are used on flat slabs, agents
containing reflective aluminium pigment shall be used.
2.20.16 (A)
Compounds shall have an efficiency rating of at least 90%
when tested in accordance with Clause 1027 of the Department
of Transport Specification for Highway Works.
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2.20.17 (A)
Where used in contact with water under preparation or
conveyance for public water supply the curing agent shall
comply with Clause 2.1 of this specification.
2.20.18 (A) Before use, the Contractor shall submit full details of the proposed
formwork release agent for approval.
2.20.19 (A)
Where used in contact with water under preparation or
conveyance for public water supply the formwork release agent
shall comply with Clause 2.1 of this Specification.
2.20.20 (A)
Refer to 2.21 for specific requirements for concrete containing
PFA or GGBS.
Yorkshire Water Standard Mixes
YW Concrete
Reference
WR2
WR3
WR4
Designated
Concrete
Reference
Freeze/
thaw XF3
resistant
SMIL
SMOD
UMB
KMF
RHS 1
RC25/3
0
RC30/3
7
GEN 3
GEN 1
PAV 2
RHS 2
Design
Strength Class
C28/35
C35/45
C35/45
C25/ 30
C30/ 37
C16/
20
C8/10
C28/35
C28/35
Design
Chemical Class
DC-2
DC-3
DC-4
DC-1
DC-1
DC-1
N/A
N/A
N/A
Nominal
Maximum Size
of Aggregate
(mm)
20
20
20
20
20
20
20
20
20
20
Freezethaw
resisting
Freezethaw
resisting
Freezethaw
resisting
CEMI,
CIIB-V or
CIIIA
CEM 111A
Type of
aggregate
Cement Types
and
Combinations
Minimum
Cementitious
Content, kg/m³
Maximum
Cementitious
Content, kg/m³
Maximum Free
Water/Cement
Ratio
CIIB-V + SR
(min 25% pfa),
CIIIA + SR
Where the
recommendatio
ns given for DC2 to DC-4m
control the
concrete
specification,
the DC-Class
should be
specified and
not the limiting
values.“ Clause
A.4.4 BS85001:2015.
CIVB-V or
CIIIB
Where the
recommendati
ons given for
DC-2 to DC4m control the
concrete
specification,
the DC-Class
should be
specified and
not the limiting
values.“
Clause A.4.4
BS85001:2015.
CIIB-V + SR
(min 25% pfa),
CIIIA + SR
Where the
recommendati
ons given for
DC-2 to DC4m control the
concrete
specification,
the DC-Class
should be
specified and
not the limiting
values.“
Clause A.4.4
BS85001:2015.
C40/50
Table
A.14
BS8500
-1:2015
Table
A.14
BS8500
-1:2015
Excl.
IVB-V
Table
A.14
BS850
01:2015
Table
A.14
BS8500
-1:2015
CEMI,
CIIB-V or
CIIIA
260
300
220
180
300
340
360
-
-
-
-
-
-
450
0.65
0.55
-
-
0.55
0.5
0.45
3.5
3.5
None
Minimum
entrained air
Content
Volume, %
Alternative
is
CEM 11BV, or CEM
11B-S or
CEM 1
NOTES:
1.
2.
3.
4.
Designated concrete GEN 0 to BS 8500-2 may be used instead of concrete KMF.
Freeze-thaw resisting aggregates must be used wherever air-entrainment is specified.
RHS 1 should not be used when the structure is subjected to de-icing agents in accordance with Table A.3
BS8500-1:2015. Where de-icing agents are used, RHS 2 should be used.
Lowest nominal cover for base slabs cast against blinding to be in accordance with Table A.9 of BS8500-1:2015.
CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
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GUIDE TO CONCRETE REFERENCES
Yorkshire Water Standard Concrete
These are standard concrete mixes from which a selection shall be made at the
design stage, as being appropriate to the works to be included in the Particular
Specification and for structures with an intended working life of at least 50 years.
Structures with 100 yr. intended working life shall be Designed mixes.
WR2
Standard concrete for water retaining structures and other structural
reinforced concrete with 30mm minimum (40mm nominal)
reinforcement cover, in severe (XC3/4 + XF1) exposure condition, see
BS 8500-1. Meets requirements of Design Chemical Class DC-2 of
BRE SD1 and BS 8500-1, suitable for use in AC-2 ground conditions.
WR3
As "WR2" but meets requirements of design chemical class DC-3 of
BRE SD1 and BS 8500-1, suitable for use in AC-3 ground conditions
when combined with the appropriate number of Additional Protective
Measures. Suitable for use in sections greater than 450mm thickness
in AC-4 ground conditions (except where very high concentrations of
magnesium are present) when combined with the appropriate number
of Additional Protective Measures. (Suitable with 40mm minimum
(50mm nominal) reinforcement cover for very severe (XD3/XS3)
exposure condition, see BS 8500-1, provided air-entrainment is used).
Where XF4 exposure class applies, refer to BS 8500-1. The minimum
strength class requirement will not necessarily ensure compliance for
minimum cement content or maximum free water/cement ratio.
WR4
As “WR2” but meets requirements of design chemical class DC-4 of
BRE SD1 and BS 8500-1, suitable for use in AC-4 and AC-5 ground
conditions when combined with the appropriate number of Additional
Protective Measures (except where very high concentrations of
magnesium are present) (Suitable for very severe (XD3/XS3)
exposure, see BS 8500-1, with 40mm (50mm nominal) reinforcement
cover provided air-entrainment used). Where XF4 exposure class
applies, refer to BS 8500-1. The minimum strength class requirement
has been increased to meet the requirements of very severe exposure
(air-entrained) but will not necessarily ensure compliance for minimum
cement cover or maximum free water/cement ratio.
SMIL
Standard concrete for structural reinforced concrete with minimum
reinforcement cover of 25mm (35mm nominal cover), other than water
retaining structures, in mild (XC2) exposure condition.
SMOD As "SMIL" but suitable with minimum reinforcement cover of 25mm
(35mm nominal) for moderate (XC3/4) exposure non-aggressive
conditions.
UMB
Standard concrete for unreinforced mass concrete sections and
blinding to water retaining structures. If sulphate resistance to Design
Chemical Class DC-2, of BRE SD1 and BS 8500-1, or above is
required, a higher grade from above must be used.
KMF
Appropriate for kerb backing and mass fill, or blinding to "SMOD" or
other non-water retaining structures.
RHS 2
Suitable for concrete roads and hard standings which are exposed to
abrasive action and are subject to severe freezing conditions whilst wet
and to the application of de-icing salts. (XD3 + XF4), see BS 8500-1.
CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
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Section 2 - Materials
2.21 CONCRETE CONTAINING PFA OR GGBS
1. For concrete mixes containing PFA or GGBS, the proportion of replacement
shall be set out as in the table below:
(i) Normal combinations of cement
can be used in suitable concrete to
provide resistance to sulphate
attack under Design Chemical
classes DC-1 and DC-2. Special
combinations can be used in
suitable concrete to provide
resistance to Design Chemical
classes 3 and 4 using additional
protective measures as appropiate.
See Table A.6 and A.11 of BS
8500-1:2015+A1:2016. For further
guidance see BRE Special Digest
No.1 ‘Concrete In Aggressive
Ground’.
(ii) Where high replacement levels
are used, special care will be
required in striking formwork and
with curing.
Cementitious
Component Other
than Cement
Use of Concrete
Percentage by Mass of
Cementitious Content
Normal
Special
15 – 35
25 – 40
PFA
Any
GGBS
Concrete designed
to retain an
aqueous liquid
0-50
70-90
GGBS
Other
0-65
70-90
2. For concrete designed to retain an aqueous liquid, the maximum cementitious
content for mixes containing PFA shall be 450 kg/m³ and the maximum free
water: cementitious ratio shall be 0.50.
(iii) The use of concrete mixes with
high replacement levels may not be
appropriate in areas subject to
abrasion.
2.22 CONCRETE - READY-MIXED
(i) Any restrictions on the use of
ready-mixed concrete in the Works
should be described in the
Contract.
(ii) A coded description for the
concrete, to obviate unnecessary
repetition of items upon delivery
tickets, may be acceptable.
(iii) Any requirements for information concerning the taking of test
cubes
or
slump
or
other
consistence determinations, should
be described in the Contract.
(iv) Any restrictions on the use of
admixtures in the Works should be
described in the Contract.
Yorkshire Water
additional, new
clauses.
Services Ltd
or substitute
1. Where concrete is to be obtained from a ready-mix supplier, the supplying
plant shall be approved by a Third Party Certification body accredited by the
United Kingdom Accreditation Service (UKAS) for product conformity.
2. The delivery ticket required for each load of ready-mixed concrete shall, in
addition to the information prescribed under BS EN 206-1:2013 Clause 7.3,
detail:
(a) the type of aggregate;
(b) the actual cementitious content and the percentage of any PFA or GGBS
included; and
(c) The position of the concrete in the Works (details to be inserted at the point
of discharge).
3. All delivery tickets shall be kept at the Site and shall be made available for
inspection
2.22.4 (A)
The delivery ticket required for each load of ready-mixed concrete
shall, in addition to the information prescribed under BS EN
206:2013+A1:2016 clause 7.3 detail:
(a) the type of aggregate
(b) the actual cementitious content and the percentage of fly ash
or ggbs included.
(c) the position of the concrete in the Works. (details to be
inserted at the point of discharge)
(d) any admixtures used
2.22.5 (A)
CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
If the use of a super-plasticizer is required, it must be approved
before use.
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Section 2 - Materials
2.23 CONCRETE - POROUS NO-FINES
1. Porous no-fines concrete shall contain CEM 1 cement to BS EN 197-1, and
20-10 mm aggregate complying with BS EN 12620 and PD 6682-1, in a
proportion of 1:10 by mass.
2. The concrete shall be mixed to a uniform colour and consistency, with the
addition of water sufficient only to coat all of the aggregate without forming excess
grout.
Yorkshire Water
additional, new
clauses.
Services Ltd
or substitute
2.23.3 (A)
Designers shall take account of site groundwater conditions and
surrounding geology when considering the use of a porous no
fines drainage layer in order to avoid the build-up of high pH
drainage water over time and its associated Health, Safety and
Environmental implications, including burns and discharge onto
the site or into waterways.
2.24 CONCRETE - AIR-ENTRAINED
(i) Air-entraining admixtures used in
conjunction with PFA can give rise
to very variable air content.
1. Air-entrained concrete shall have a minimum air content by volume of the fresh
concrete at the time of placing, in accordance with BS 8500-1:2015+A1:2016
Table A.8.
2.25 CONCRETE - CHLORIDE CONTENT
1. Chloride content of fresh concrete shall be determined in accordance with BS
EN 206-1:2013 Clause 5.2.7.
2. Methods for determining the chloride contents of constituent materials shall be
in accordance with BS 8500-2.
2.26 CONCRETE - PIPES AND FITTINGS
(i) Particular requirements from the
options listed in BS EN 1916 and
BS 5911-1 should be described in
the Contract.
(ii) Additional protective measures
required by BRE Special Digest
No.1 to provide resistance to the
actual ACEC (Aggressive Chemical
Environment for Concrete class)
should be described in the
Contract.
1. Unreinforced and reinforced concrete pipes and fittings shall comply with the
relevant provisions of BS EN 1916 and BS 5911-1.
2. All pipes and fittings shall have gasket-type joints of spigot and socket or
rebated form.
3. Unreinforced and reinforced concrete jacking pipes shall comply with the
relevant provisions of BS EN 1916 and BS 5911-1. Pipes shall withstand the
jacking loads to which they will be subjected during installation, without cracking
or spalling. A certificate shall be supplied to the Client, confirming that the pipes
are suitable for jacking and stating the distributed jacking loads for which they
were designed.
Yorkshire Water
additional, new
clauses.
Services Ltd
or substitute
2.26.1 (S)
Unreinforced and reinforced concrete pipes and fittings shall
comply with the relevant provisions of BS EN 1916 and BS 5911:
Part 1.
Yorkshire Water
additional, new
clauses.
Services Ltd
or substitute
2.26.4 (A)
All concrete pipes and fittings shall be manufactured using either
Sulphate Resisting Cement or a blend of (Ordinary) Portland
Cement (CEM I) and Fly Ash or Ground Granulated Blast furnace
Slag to satisfy the requirements of Design Chemical Class DC-4,
unless otherwise stated in the Particular Specification. Additional
Protective Measures shall be provided as required by BRE
SD1and BS 8500-1 to provide resistance to the actual Design
Sulphate Class. . The compiler of the Particular Specification shall
check their requirements and specify accordingly, especially for
extremely aggressive environments. The Intended Working Life
for each asset is specified in Section 3.1.
2.26.5 (A)
Concrete pipes and fittings shall not be utilised for buried
pressurised water pipelines without the express consent of the
Employer.
2.26.6 (A)
Test results and certificates are available from the supplier on
request, and these should be inspected from time to time to ensure
compliance with the required standards. Inspections should be
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Section 2 - Materials
made randomly and at least once annually, once for every job, and
on change of supplier.
2.26.7 (A)
Where grouting is required in the Contract concrete jacking pipes
shall include sufficient grout holes to facilitate grouting.
2.27 CONNECTORS FOR TIMBER
1. Connectors for timber shall comply with the relevant provisions of BS EN 912.
2.28 COPING UNITS
(i) The required type of cement for
cast coping units should be
described in the Contract.
1. Precast concrete, cast stone, clayware, natural stone and slate coping units
shall comply with the relevant provisions of BS 5642-2. Slate coping units shall
be Type B.
(ii) In areas of high air pollution,
Type A slate coping units may be
required.
2.29 COPPER PIPES AND FITTINGS
1. Copper pipe for use with potable water shall comply with the relevant
provisions of BS EN 1057.
2. Copper and copper alloy compression fittings for polyethylene pipes shall
comply with the relevant provisions of BS EN 1254-3.
2.30 COVER BLOCKS AND SPACERS FOR REINFORCEMENT
1. Cover blocks and spacers shall comply with BS 7973-1. To maintain the correct
clear cover of concrete over steel reinforcement they shall be as small as
possible, consistent with their purpose.
2. Concrete cover blocks shall be manufactured with a 10 mm maximum
aggregate size and otherwise produced to the same specification as the
surrounding concrete. Wire cast in the block for the purpose of tying it to the
reinforcement shall comply with Clause 2.128.
3. Spacers shall be of rust-proof material and shall not produce staining or
otherwise be detrimental to the concrete or steel.
Yorkshire Water
additional, new
clauses.
Services Ltd
or substitute
2.30.4 (A)
All cover blocks and spacers shall be manufactured by a proprietary
manufacturer. Site made spacers will not be acceptable.
2.31 DAMP-PROOF COURSES
(i) Detailed requirements for dampproof courses should be described
in the Contract.
1. Damp-proof course materials shall comply with the requirements of the
Standards, as set out below:
Material
Yorkshire Water
additional, new
clauses.
Services Ltd
or substitute
Standard
Bitumen
BS 6398
Polyethylene
BS 6515
Other
BS 743
2.31.1 (S)
CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
Sheet damp proof courses shall consist of sheets complying with
BS 743:1970 plus the 1978 amendments or BS 8215: 1991.
Polythene damp proof membranes shall have a minimum nominal
thickness of 460 microns.
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Section 2 - Materials
2.32 DOORS, FRAMES AND LININGS
(i) Detailed requirements for doors
should be described in the
Contract.
1. Dimensions and tolerances for wood door sets, door leaves and frames shall
be in accordance with the relevant provisions of BS 4787-1. Match boarded doors
shall comply with the relevant provisions of BS 459.
(ii) Particular requirements for wood
door frames and linings (except
those for fire-check flush doors)
should be described in the
Contract.
2. Dimensions and tolerances for non-wood door sets, door leaves and frames
shall be in accordance with the relevant provisions of BS 4787.
3. Steel doors in wooden frames shall comply with BS 1245.
2.33 DOWEL BARS
(i) Stainless steel should be
specified in the Contract when
chlorides are present.
1. Dowel bars for expansion joints in concrete shall consist of mild steel
complying with the provisions of BS EN 13877-3.
2.34 DRAW CORD
1. Draw cord for duct threading shall be 8 mm diameter, 3-strand hawser laid
polypropylene rope, complying with BS EN ISO 9554 and BS EN ISO 1346.
2.35 DRESSED NATURAL STONE KERBS, CHANNELS, QUADRANTS AND
SETTS
(i) The required size and type of
setts should be described in the
Contract.
1. New dressed granite and whinstone kerbs, channels, quadrants and setts shall
comply with the relevant provisions of BS EN 1342 and BS EN 1343.
2. Second-hand stone kerbs, channels, quadrants and setts shall not be
excessively weathered, worn or chipped and shall be free from all bedding and
jointing materials. Faces which are to remain exposed on completion shall be free
from stains.
2.36 DUCTILE IRON, CAST IRON AND STEEL PIPES, FLANGES AND
FITTINGS
(i) IGN 4-21-01 deals with ductile
iron pipes and fittings.
1. Ductile iron pipes, fittings and joints shall comply with BS EN 545 for potable
water pipelines, BS EN 598 for sewerage applications and BS EN 969 for gas.
(ii) The type and class of pipes,
joints, fittings, gaskets, nuts, bolts
and washers should be detailed in
the Contract.
2. Cast iron pipes, fittings and joints for rainwater and soil drainage shall comply
with BS EN 877.
(iii) The required grade and
thickness of steel, together with the
type and strength of pipe, should be
described in the Contract.
(iv) Dimensions are specified in BS
EN 545 for integral flanges on
ductile iron pipe. Flange facings
can either be flat or raised face.
Flanges in accordance with BS EN
545 and BS EN 598 are
dimensionally compatible with BS
EN 1092-1 and BS EN 1092-2.
(v) The nominal bar pressure rating
for the pipes and flanges should be
selected to meet the duty
requirements and should be
described in the Contract.
(vi) The type of anti-corrosion
(barrier) coatings for ductile iron
pipes and fittings should be detailed
in the Contract, taking into account
the requirements of BS EN 545 and
BS EN 598. In the UK, three
systems of external corrosion
3. Steel pipes and fittings shall conform to BS EN 10224-L275 Option 1:S or
SAW. Joints shall conform to BS EN 10311.
4. Flanges for pipes and pipeline fittings shall comply with BS EN 1092-1 for steel
and BS EN 1092-2 for ductile and cast iron.
5. Factory-applied coatings shall be in accordance with BS ISO 8179-1. Where
external zinc spray and a bituminous finishing layer are applied, this shall be in
accordance with BS EN 545.
6. Factory-applied and Site-applied (tubular) polyethylene sleeving shall be in
accordance with BS 6076.
7. Cement mortar linings for potable water pipelines shall comply with the
requirements of BS EN 545. Where a seal coat is required, it shall comply with
the requirements of BS ISO 16132 and the complete system shall be approved
under the Water Supply (Water Quality) Regulations 2000. In addition, the
Instructions for Use issued by the Drinking Water Inspectorate as part of the
approval shall be followed.
8. Tubular polyethylene film for use as a loose protective sleeving for buried iron
pipes and fittings shall comply with the relevant provisions of BS 6076, except
that the nominal lay flat width shall be 280 mm for use with 80 mm and 100 mm
nominal internal diameter pipelines incorporating push-in flexible joints, and 400
mm for 150 mm nominal internal diameter pipelines. Sleeving for pipes for belowground use for potable water shall be coloured blue and all other sleeving black.
Joints in sleeving shall be taped so as to form a continuous barrier and any
damage to the sleeving shall be repaired prior to backfilling.
9. Bituminous coatings shall comply with BS 3416.
CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
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Section 2 - Materials
protection are employed: zinc spray
with bituminous finishing layer with
or
without
overwrapping
of
polyethylene sleeving, or zinc (or
zinc/aluminium) spray with epoxy
finishing layer. IGN 4-51-01 deals
with external zinc coating of ductile
iron pipe which is required on all
pipes in the diameter range 801600 mm. WIS 4-52-01 and IGN 452-02 deal with polymeric anticorrosion (barrier) coatings.
(vii) Any additional external
protection for pipes laid in
contaminated land should be
described in the Contract.
(viii) Any requirement for coatings
to steel pipes should be described
in the Contract.
(ix) The thickness of polymeric anticorrosion (barrier) coatings should
be such that the chemical
resistance test in BS EN 598:2007
Section 5.6 is met.
(x) In the UK, ductile iron pipes lined
with cement mortar may require an
epoxy or acrylic seal coat over the
cement to prevent lime leaching
with certain potable waters. This
should be described in the
Contract.
(xi) The use of polyethylene factoryapplied sleeving as an alternative to
loose sleeving should be stated in
the Contract. IGN 4-50-03 gives
operational guidelines for the
transportation, handling and laying
of ductile iron pipes with factoryapplied polyethylene sleeving.
Yorkshire Water
additional, new
clauses.
Services Ltd
or substitute
2.36.4 (S)
The nominal flange rating to be utilised shall be NP16 unless
otherwise described in the Particular Specification. For
applications with a working pressure greater than 16 Bar the
Contractor shall select the nominal flange pressure rating
appropriate to the selected application.
2.36.5 (S)
Factory-applied coatings shall be in accordance with BS ISO
8179-1 and BS ISO 8179-2. Where external zinc spray and a
bituminous finishing layer are applied, this shall be in accordance
with BS EN 545:2010 Clause 4.4.2. Other factory applied
coatings can be used for appropriate external environments and
these shall comply with the following standards: 400g/m2 80/20
zinc/aluminium alloy or pseudo alloy with an polymeric top coat in
accordance with BS EN 545:2010, External cement mortar
coating in accordance with BSEN 15542:2008, External
Polyurethane coating for pipes in accordance with BSEN
15189:2006, Internal and external epoxy coating of fittings in
accordance with BS EN 14901:2014, External Polyethylene
coating for pipes and fittings in accordance with BSEN 14628:
2005.
CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
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Yorkshire Water
additional, new
clauses
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or substitute
Section 2 - Materials
2.36.10 (A)
Any pipe supplied to convey water for public water supply before
or after preparation, that has approval under Regulation 31, 1 (a)
with only a cement mortar lining, shall require specific approval
from the Employer’s Manager of Water Quality prior to
specification, purchase or use. Pipe fittings may be supplied with
cement mortar linings or thermoplastic coatings inside and out in
accordance with WIS 4-52-01 or BS EN 14901:2014.
2.36.11 (A)
External corrosion protection systems for ductile iron pipe shall be
chosen according to the soil types, level of water table and soil
resistivity through which the main shall be laid. This shall be
evaluated at regular intervals along the proposed pipeline route at
a frequency determined by changes in elevation, land use, soil
moisture content and other visual indicators that changes in
relevant factors may occur. These measurements shall be taken
wherever practical at the proposed depth of pipe burial as
conditions can vary significantly with depth. The appropriate
means of external protection shall then be selected in accordance
with the Guidance in Annex D of BS EN 545." The minimum level
of protection that will be permitted on pipe in accordance with
BSEN 545 or 598 shall be 400 grams per square metre of an 80/20
alloy/pseudo alloy of zinc aluminium with a finishing layer of
bituminous or resin paint. Where required by the site conditions
higher levels of protection may be utilised. It is possible for
reasons of performance and economy that a higher level of
protection may be required by the YWS Procurement Framework
specification and that specification shall be applied in all cases
where practicable when procuring pipe.
2.36.12 (A)
Fittings supplied with polymeric internal and external coatings
shall comply with Water Industry Standard 4-52-01 or BS EN
14901:2014. All internal and external surfaces shall be coated to
Class B as a minimum.
2.36.13 (A)
Where pipes, flanges and fittings are to be immersed in water
under preparation or conveyance for public water supply, the
external coating shall comply with clause 2.1 of this specification
and provide adequate corrosion protection for this application.
2.36.14 (A)
Bitumen lining is not acceptable.
2.36.15 (A)
Ferrous pipes of less than 50mm may be joined by threaded joints
to BS 21 (BS EN 10226-1:2004) or welding.
2.36.16 (A)
Where mating faces are to be protected, the coating shall be
uniform and even. Such coating shall be checked before jointing
and any unevenness removed.
2.36.17 (A)
Steel pipe for water under preparation or conveyance for public
water supply applications shall be internally coated with solventfree epoxy to a minimum thickness of 500 microns. The pipe lining
and method of application shall comply with Clause 2.1.
2.36.18 (A)
Steel pipe for water under preparation or conveyance for public
water supply applications shall be externally coated by one of the
following methods:
a) three layer extruded polyethylene (PE) or polypropylene (PP)
coating consisting of initial fusion bonded epoxy layer, PE/PP
adhesive layer and minimum 2.75mm thick PE/PP hot
extruded coating.
b) minimum 3mm thick hot applied bitumen enamel wrap in
accordance with BS 534.
2.36.19 (A)
Steel pipe for sewerage shall be internally coated in accordance
with WIMES 4.01 and/or clause 2.36 and externally coated as
detailed in the Particular Specification.
2.36.20 (A)
Stainless steel pipe shall be of an approved grade of Stainless
Steel, fabricated by an approved entity – CPP listed.
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2.37 ELECTRODES, FILLER RODS AND WIRES FOR WELDING
(i) BS EN 1011-3 applies to the arc
welding of stainless steel, but not to
the welding of stainless steel tubes
or to sections greater than 6 mm
thick.
1. Electrodes, filler rods and wires for welding shall be compatible with the grade
of steel to be welded.
2. Electrodes for the manual metal-arc welding of carbon and carbon manganese
steel and stainless steel shall comply with the relevant provisions of BS EN ISO
2560 and BS EN 1600, respectively.
3. Electrode wires and fluxes for the submerged arc welding of carbon steel and
medium tensile steel shall comply with the relevant provisions of BS EN ISO
14171.
4. Filler rods and wires for gas-shielded arc welding shall conform to the
Standards in the table below:
Metal
Standard
Non alloy and fine grained steels
BS EN ISO 14341
Stainless and heat resisting steels
BS EN ISO 14343
Aluminium and aluminium alloys
BS EN ISO 18273
5. Manual welding of stainless steel shall be by the inert-gas tungsten-arc
process.
Yorkshire Water
additional, new
clauses
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or substitute
2.37.1 (S)
Replaces all clauses 1 to 5.
Electrodes, filler rods and wires for welding shall be in accordance
with the requirements of Clause 6.20.
2.38 EXPANDED METAL ANGLE BEADS
1. Expanded metal angle beads shall conform to BS EN 13658-1 for internal
plastering and BS EN 13658-2 for external rendering.
2.39 FERTILISER
(i) The general purpose compound
should be used as a single
application, prior to seeding, where
good root establishment but slow
growth is required. The pre-seeding
and
post-establishment
compounds require application
both before and after germination,
respectively, and will promote good
root establishment followed by
rapid growth.
1. Fertilisers shall consist of compounds containing urea nitrogen, phosphoric
acid and potash in the proportions by mass, as set out below:
Chemical
General
Purpose
Pre-seeding
Postestablish
ment
Urea nitrogen
5%
-
46%
Phosphoric acid
15%
21%
-
Potash
15%
12%
-
(ii) The compounds are not
intended for use on agricultural
land,
where
the
farmer's
requirements
should
be
ascertained.
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2.39.2 (A)
Details of all fertilisers proposed for use shall be submitted for
approval.
2.40 FIELD GATES
(i) Fittings and dimensions for
gates should be described in the
Contract.
1. Steel field gates, fittings and posts shall be hot dip galvanised in accordance
with BS EN ISO 1461.
2. Timber field gates and posts shall comply with the requirements of BS 3470.
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2.41 FIXING ACCESSORIES FOR BUILDING PURPOSES
1. Fixings for sheet, roof and wall coverings shall comply with the relevant
provisions of BS 1494-1.
2.42 FIXINGS FOR METALWORK
(i) Sizes and types of fixings should
be described in the Contract,
together
with
minimum
requirements for edge distances,
centres of fixings and embedments.
(ii) For guidance on the selection
and use of fixings in concrete and
masonry, see CIRIA Technical
Note TN137.
(iii)
BS
6180
recommendations
for
protective barriers.
gives
fixing
(iv) BS 5080-1 does not give
recommendations on the interpretation of the results of tests for
the purposes of design, selection or
use of fixings. CIRIA Technical
Note TN75 deals with loading tests
on fixings in concrete.
1. Mild steel bolts and nuts shall be hot dip galvanised in accordance with BS EN
ISO 1461. Mild and high tensile steel proprietary fixings shall be protected in
accordance with the relevant provisions of the appropriate Standard, as set out
below:
Type of Protection
Type of Fitting
Cast-in, Having
No Machined
Thread
Cast-in/Expanding, Basic Major
Diameter of Machined Thread
Hot dip galvanised
BS EN ISO
1461
-
-
Electroplated zinc
BS EN ISO
2081
Zn 10
BS 7371-12
BS EN ISO
2081
Zn 10
(v) Where described in the
Contract, axial and shear loading
tests on structural fixings in
concrete or masonry should be
carried out in accordance with the
provisions of BS 5080-1 and BS
5080-2, respectively. The safe
working load should be as
described in the Contract.
2. Stainless steel proprietary fixings, bolts and nuts shall be manufactured from
Grade X5 CrNiMo 17-12-1 steel complying with BS EN 10088.
Yorkshire Water
additional, new
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2.42.2 (S)
Stainless steel proprietary fixings, bolts and nuts shall be
manufactured from Grade X5 CrNiMo 17-2-2 steel complying with
BS EN 10088, and shall comply with BS EN ISO 3506
2.42.3 (S)
Where dissimilar metal are used in a connection refer to clause
2.146 for isolation requirements.
2.42.4 (A)
Where contact with water under preparation or conveyance for
public water supply occurs all bolts, nuts, washers and fixings shall
be of stainless steel.
2.42.5 (A)
The grades of hardness of stainless steel used in bolts and
associated fixings shall be such as to avoid seizing problems. An
anti-seize lubricant shall be used that complies with Clause 2.1.
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Services Ltd
or substitute
3. Where fixings are metallurgically incompatible with the material being fixed,
suitable isolating washers and sleeves shall be used.
2.43 FLASHINGS
(i) Any requirement for a different
material or thickness of sheet
should be described in the
Contract.
1. Flashings shall comprise milled lead strip complying with BS EN 12588.
2.44 FLEXIBLE COUPLINGS
1. Flexible couplings for gravity sewerage and drainage pipes shall comply with
the provisions of BS EN 16397 – 1&2 2014 and BS EN 295-4.
2.45 FLOOR TILES
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(i) Facial sizes, thickness, colour
and, in the case of floor quarries,
category, should be described in
the Contract.
(ii) Requirements for slip resistance
should be described in the
Contract.
Section 2 - Materials
1. Floor tiles shall comply with the relevant provisions of the appropriate Standard,
as set out in the following table:
Type
Standard
Ceramic
BS EN 14411
Thermoplastics
BS EN 649
Semi-flexible PVC
BS EN 654
Unbacked flexible PVC
BS EN 649
Terrazzo – internal use
BS EN 13748-1
Terrazzo – external use
BS EN 13748-2
2.46 FOAMED CONCRETE
(i) The Contract should indicate
where foamed concrete may be
used in reinstatement.
1. Foamed concrete used in the reinstatement of roads, streets and highways
shall comply with the requirements of the relevant Highway Reinstatement
Specification.
2.47 FOAM SWABS
(i) The ratio of swab length to
diameter and the diameter of the
swabs for different pipe sizes
should be detailed in the Contract.
1. Swabs for cleaning water mains shall be solid, cylindrical polyurethane foam,
in accordance with BS EN ISO 5999.
(ii) The swab density and
coarseness should be detailed in
the Contract for each application.
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additional, new
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2.47.1 (S)
Refer to YWS IMS Distribution Infrastructure for Swabbing
Requirements.
2.48 GABIONS AND ROCKFILL MATTRESSES
(i) The design of the units (e.g.,
weld or woven mesh divided by
partition
panels),
including
additional protection, should be
stated in the Contract.
(ii) The method, type and grading of
the fill material should be stated in
the Contract.
1. All gabion boxes and mattresses shall be formed from 4 mm steel wire. All wire
shall be in accordance with BS 1052 and hot dip galvanised with a zinc coating
to BS EN 10244-2.
2. Units shall be filled with hard, durable and clean rock, The stone shall be well
graded between 100 mm and 150 mm. The units shall be assembled and filled in
accordance with the manufacturer’s instructions.
2.49 GASKETS FOR FLANGED AND PUSH-FITJOINTS
(i) Requirements for full face or
inside-bolt-circle
type
gaskets
should be described in the
Contract.
(ii) Gasket material and type of ring
should be selected for the intended
duty and be stated in the Contract.
1. Gaskets for flanged pipe joints shall be either of the inside-bolt-circle type or
full face type.
2. Gaskets shall be manufactured from material complying with the provisions of
BS EN 681-1 or BS EN 681-2, as appropriate.
3. For potable water, gaskets shall be Type WA with a hardness range of 76-84.
4. For sewerage, gaskets shall be Type WC or WG with a hardness range of 7090.
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Yorkshire Water
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2.49.1 (S)
Gaskets shall be of the double lugged inside bolt circle or full face
type for flange diameters up to and including DN 250mm and for
flange diameters greater than this they shall be of the full face type
only. This is to ensure correct gasket location and secure retention
in service. All gaskets for jointing of ferrous to ferrous flange joints
shall be of the full face gasket type. All gaskets except reinforced
materials shall be of the full face type e.g. steel cored EPDM. The
dimensions of gaskets shall comply with BS 4865: Part 1. Gaskets
shall be manufactured from 3mm thickness 80deg shore hardness
EPDM sheet to BS EN 681, Type WA and meet the
biodeterioration test performance criteria contained in the previous
BS 2494 when tested against BS 7874.
Yorkshire Water
additional, new
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Services Ltd
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2.49.5 (A)
All gaskets for metric flanged pipe joints shall comply with the
dimensions contained within BS EN 1514 Part 1 except that they
shall be “tru-bore” i.e. the bore of the gasket shall be equal to the
nominal bore of the pipe sizing they are jointing.
2.49.6 (A)
Proprietary gasket types with stiffening components that are of the
inside bolt circle type may also be utilised, providing they meet fully
with the standards contained in this clause.
2.49.7 (A)
For jointing PE stub flanges up to and including 10bar operating
pressure full face “true bore” gaskets shall be used i.e. gaskets cut
with an inner diameter approximating to the inner diameter of SDR
17 PE100 pipe. For jointing PE stub flanges with an operating
pressure in excess of 10bar reinforced gaskets shall be used in
accordance with the fittings manufacturers’ instructions. All bolt
sets should be installed with a torque wrench following the
fittings manufactures instructions, and sequencing. All bolt
sets should be re-checked prior to back filling and
reinstatement..
2.50 GENERAL FILLING MATERIALS
(i) BRE Digest 276 deals with
hardcore.
1. Hardcore shall consist of clean, hard, durable material, uniformly graded from
200 mm to 20 mm and be free from extraneous matter.
2. Selected fill, whether from locally excavated material or imported, shall consist
of uniform, readily-compactible material. Fill shall be free from vegetable matter,
building rubbish and frozen material or materials susceptible to spontaneous
combustion. It shall exclude clay of liquid limit greater than 80 and/or plastic limit
greater than 55, and materials of excessively high moisture content. Clay lumps
and stones retained on 75 mm and 37.5 mm sieves, respectively, shall be
excluded from the fill material.
3. Quarry scalpings shall consist of hardstone passing a 38 mm screen and shall
contain sufficient dust to enable the material to bind together when consolidated
with water and rolled. The clay fraction shall not exceed 10%.
2.51 GLASS FOR GLAZING
(i) BS EN 952-2 deals with
terminology for work on glass.
1. Glass for glazing shall comply with the relevant provisions of BS EN952.
(ii) Requirements for glass should
be described in the Contract.
2.52 GLASS REINFORCED PLASTICS (GRP) PIPES AND FITTINGS
(i) The pressure rating and loading
of pipes and fittings should be
stated in the Contract.
1. Glass reinforced plastics (GRP) pipes and fittings shall comply with the relevant
provisions of BS EN 14364 for sewage and drainage applications or BS EN 1796
for water supply.
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Yorkshire Water
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Section 2 - Materials
2.52.2 (A)
GRP pipe and fittings shall only be utilised with prior written
consent (specific to a scheme) from the Employer. This will apply
from feasibility and initial design stage and through all stages of
the procurement process, up to and including installation. This
consent will only be provided once the pipe and fittings
specification has been sanctioned by the Employer as being
appropriate for all aspects of the specific pipeline’s installation,
operating conditions and service life. Additional performance,
materials and test requirements will form part of the agreed
specification.
2.53 GLASS REINFORCED PLASTICS PRODUCTS
(i) Finish colour for GRP products
should be stated in the Contract.
1. GRP vessels and tanks shall be designed and manufactured in accordance
with BS EN 13923 and BS EN 13121-3.
2. GRP pultruded profiles shall be manufactured in accordance with BS EN
13706-2 and BS EN 13706-3. The material shall be a composite of thermosetting
resin reinforced to a minimum content of 25% with continuous glass fibre
complying with BS EN 14020-2 and BS EN 14020-3, with an equal number of
layers in each direction. The material shall incorporate UV inhibition. The glass
content shall not exceed 40% by weight. Orthophthalic polyester shall not be used
on wastewater applications in aggressive environments or where frequent
handling is likely.
3. Finished surfaces shall be smooth and uniform, and fibres shall be fully
embedded. The top layer of reinforcement shall have sufficient resin cover to
provide maximum stiffness and prevent resin chipping from unreinforced edges.
There shall be no evidence of fibre orientation irregularities, inter-laminar voids,
resin-rich or resin-starved areas. Fabrications shall be protected and sealed
against penetration of water and dirt. Cut edges of mouldings or pultruded
sections shall be fully sealed with a suitably compatible resin. The finished
material shall have a minimum Barcol hardness of 35 when tested in accordance
with BS 2782-10.
2.54 GLAZING MATERIALS
(i) Special requirements may be
necessary for putty or other
materials for use with double
glazing.
1. Linseed oil putty for use in glazing wooden frames shall comply with BS 544.
2. Material for use in glazing metal frames shall be a non-setting, synthetic
compound of oils, plasticisers and polymers, for gun, knife or strip application,
and shall contain an agent to produce a surface skin to minimise dirt retention.
2.55 GRANULAR SUB-BASE MATERIAL
(i) The use of recycled material
should be encouraged and should
be described in the Contract.
(ii) Recycled material for use in subbases is defined in the Highway
Agency’s ‘Specification for Highway
Works’, Series 800 Clause 807
“Type 4 (Asphalt Arisings) Unbound
Mixture”.
(iii) IGN 4-08-01 gives guidance on
pipe bedding materials.
1. Granular sub-base material shall be natural sands, gravels, crushed rock,
crushed slag, crushed concrete or well burnt non-plastic shale. The material shall
be well graded and lie within the following grading limits:
BS 410-1 and BS 410-2
Test Sieve
Percentage by Mass Passing
Type 1
Type 2
100
100
37.5 mm
85-100
85-100
20 mm
60-100
60-100
10 mm
40-70
45-100
5 mm
25-45
25-85
600 µm
8-22
8-45
75 µm
0-10
0-10
75 mm
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2. Where granular sub-base material is to be used within 450 mm of the surface
of any road, the material shall have a heave not greater than 15 mm when tested
in accordance with BS 812-124.
3. Natural sands and gravels shall be permitted in Type 2 material. Natural sands
up to 12% only shall be permitted in Type 1 material.
4. The particle size shall be determined by the washing and sieving method of BS
EN 933-1. The material passing a 425 µm BS sieve, when tested in accordance
with BS 1377-2, shall be non-plastic for Type 1 and have a Plasticity Index of less
than 6 for Type 2.
5. With the exception of well burnt non-plastic shale, the material shall have a
“ten per cent fines” value of 50 kN or more when tested in accordance with BS
812-111.
6. Type 1 material shall be delivered to Site with a moisture content within + 1%
and – 2% of optimum as determined in accordance with BS 5835-1, and shall be
protected, so as to be maintained within this range, until its incorporation into the
Works.
7. Recycled materials shall comply with all relevant Standards and Clause 2.55.
8. Type 4 granular material shall be a crushed waste concrete product. The
material shall lie within the grading envelope of Table 8/5 of the ‘Specification for
Highway Works’, and not be gap graded.
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2.55.9 (A)
Material for sub-base shall be Type 1.
2.55.10 (A)
All recycled granular sub-base material shall be approved by
YHAUC and conform to the relevant specification.
2.56 GRASS SEED
(i) The required grass seed mixture
should be described in the
Contract.
1. Grass seed shall be a tested blend of named varieties, and certificates of purity
and germination shall be provided. The blend shall consist of one of the following
mixtures:
(ii) The four mixtures given are
available nationally, examples of
their individual application being as
follows:
Mixture
Application
General application which
will give satisfactory
germination on a wide
variety of soils
2
Variety
Percentage by Mass
Mixture 1
Mixture 2
Mixture 3
Mixture 4
Dwarf Leafy Perennial
Ryegrass
20-30
-
-
-
Heavy soils and wet
areas
Smooth-stalked Meadow
Grass
25-35
-
20-30
0-15
3
Drier, less fertile soils
Rough-stalked Meadow
Grass
-
15-25
-
-
4
Soils with very low
fertility, low pH or sandy
soils
Creeping Red Fescue
30-40
40-50
35-45
20-50
Fine Leaved Sheep’s
Fescue
-
-
10-20
10-40
Chewings Fescue
-
-
-
10-40
5-15
5
1
5
5-15
0-10
Crested Dogstail
-
-
5-15
-
Timothy
-
2
0
-
-
1
(iii) All mixtures have been selected
to provide slow-growing grass with
a low maintenance requirement.
Mixture 1 will give the most rapid
cover after germination but will
require more maintenance than
Mixtures 2, 3 and 4.
(iv) The mixtures are not intended
for use on agricultural land or other
landwhich may have special
requirements. In these cases, the
Browntop Bent
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owner’s
and/or
occupier’s
requirements
should
be
ascertained.
3
0
White Clover
-
-
-
0-10
(v) For guidance on the use of grass
in hydraulic engineering practice,
see CIRIA Report R116.
(vi) In view of the requirements of
the Wildlife and Countryside Act
1981, consideration should be
given, where appropriate, to the
inclusion of an approved wild flower
mix with the grass seed.
2.57 GRUMMETS
1. Grummets shall be of gel-impregnated hemp or plastic and have a thickness
before compression of not less than 10 mm. Grummets shall be a tight fit on and
shall have an external diameter at least 25 mm greater than the bolts on to which
they are fitted.
2.58 GULLIES AND GULLY COVER SLABS
1. Precast concrete gullies and gully cover slabs shall comply with the relevant
provisions of BS 5911-6.
2. Vitrified clay gullies shall comply with the relevant provisions of BS 65.
3. PVC-U gullies shall comply with BS 4660.
2.59 GULLY COVERS, GRATINGS AND FRAMES
(i) Some Highway and Roads
Authorities demand a particular slot
configuration for gully gratings,
depending upon the road gradient.
1. Gully covers, gratings and frames shall comply with the relevant provisions of
BS EN 124, BS 7903 and ‘Highways Agency Guidance Document HA 104/09’.
(ii) BS EN 124 is a minimum
performance standard only.
2.60 HANDRAILS AND BALUSTERS
(i) Where stainless steel tubes are
to be bent to very small radii, it may
be necessary to describe their
condition as GKM(S) instead of KM.
(ii) BS 6180 deals with permanent
protective barriers designed to
resist vehicular impacts.
1. Protective barriers shall conform to BS 6180 with loading determined from
Table NA.8 from the UK National Annex to BS EN 1991-1-1:2006.
2. Metal handrails and balusters shall be manufactured from materials conforming
to the appropriate Standard as set out below:
Standard
Grade
Mild steel – solid
BS EN 10025-2
S275
(iii) BS EN ISO 14122-3 gives
guidance on the construction of
guardrails.
Mild steel – tubular
BS EN 10255
HFW2
Stainless steel – solid
BS EN 10088-3
1.4401
(iv) Aluminium handrails and
balusters should not be used in
sewers, sewer manholes, sewage
pumping stations or confined
spaces in sewage treatment works.
Stainless steel – tubular
BS EN 10296-2
LW17KM
Aluminium – solid
BS EN 1559-1 and
BS EN 1559-4
EN AW 6082
Aluminium – tubular
BS EN 573-3
EN AW 6082
(v) Any requirements for toeboards
and infill panels should be
described in the Contract.
3. GRP handrails and balusters shall be manufactured from pultruded sections
conforming to BS EN 13706-2 and BS EN 13706-3. The surface shall be smooth
with fibres embedded and sealed against penetration from dirt and water. The
Barcol hardness of the sections shall be at least 35 when tested in accordance
with BS 2782-10.
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4. After manufacture, mild steel handrails and balusters shall be hot dip
galvanised in accordance with BS EN ISO 1461.
5. After manufacture, aluminium handrails and balusters shall be anodised in
accordance with BS EN ISO 7599, Grade AA25.
2.61 HYDRANTS
(i) Fire hydrants should be
compatible with the requirements of
the local Fire Authority.
1. Hydrants, surface box frames and covers shall comply with the relevant
provisions of BS 750 and BS EN 14339. Fire hydrants shall be of the screw down
type (Type 2) and close in a clockwise direction.
(ii) The required type of hydrant,
dimensions of surface box frames
and covers, and size, type and
material of hydrant indicator plates
should be described in the
Contract.
2. Hydrant box covers shall be provided with recesses for lifting keys.
(iii) Screw-down type hydrants with
loose valve plungers may not
permit the passage of swabs.
3. Hydrant indicator plates shall comply with the relevant provisions of BS 3251.
4. The surfaces of all the hydrant components shall be protected from corrosion
either by the nature of their material of construction or by coating in accordance
with WIS 4-52-01. Internal water-wetted surfaces shall be coated to Class A
standard; all other surfaces shall be coated to Class B.
5. All fasteners used in the assembly of hydrants shall be protected in accordance
with Clause 2.86.
(iv) The direction of closure should
be stated in the Contract.
6. The frame and cover shall be Grade A to BS 750 and BS EN 14339 and have
a clear opening of not less than 380 x 230 mm.
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additional, new
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2.61.2 (S)
Hydrant box covers shall be provided with recesses for lifting keys.
The cover shall be of such a design that it is capable of being lifted
by the application of a single chisel ended lever, without risk of
falling into the chamber.
Yorkshire Water
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2.61.7 (A)
Hydrants shall have a screwed outlet constructed of gunmetal or
stainless steel in accordance with the requirements of BS 750.
2.61.8 (A)
Hydrants shall be fitted with a frost plug of the blank plug type
although automatic drain plus will be accepted. The spindle cap
shall be secured by a non-corrodible fastener on to stem.
2.61.9 (A)
All hydrant installations shall be adjusted by means of riser pipes
such that the top of their threaded outlet is no deeper than 300mm
below the upper surface of the cover.
All hydrants shall be installed in a chamber with its foundation slab
above the tee off the main or the duckfoot bend. The chamber
shall have minimum internal dimensions of 430mm x 280mm clear
opening. The frame and cover shall be Grade A to BS 750 and
have a clear opening of not less the 380 x 230mm.The Contractor
shall ensure that the hydrant is vertical and that a standpipe can
be fixed to the outlet and operating key utilised without being
impeded by the frame or chamber walls.
2.61.10 (A)
2.61.11 (A)
All hydrants installed as washouts and fire hydrants shall be of the
“throughbore” type and be acquired through the YWS
Procurement framework.
All hydrants for permanent installation on YWS networks shall be
“kitemarked” by BSi Product Services (or 3rd party certified by
another accredited certification body to BS750 agreed with the
Employer).
2.62 IMPORTED TOPSOIL
(i) For the definition of in-situ topsoil
see Clause 3.3.
(ii) Any requirements for testing for
club root and eelworm should be
described in the Contract.
1. Imported topsoil shall comply with BS 3882 and be of light or medium texture,
having a pH value of between 6.0 and 7.5. Imported topsoil shall not contain
stones greater than 20 mm in size nor have a total stone content exceeding 10%
by mass.
2. Organic topsoil shall be imported from an organic land estate having a soil
composition from a similar soil series. Details of the source and composition of
the topsoil shall be provided, unless stated in the Contract.
(iii) Attention is drawn to Section
14.2 of the Wildlife and Countryside
Act
1981,
which
prohibits
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deposition of any plant material
from any non-native invasive
species listed in Part 2 of Schedule
9 of the Act (e.g. Giant Hogweed or
Japanese Knotweed).
(iv) Organic land is defined as land
cultivated without the addition of
artificial fertiliser or use of
pesticides or herbicides for at least
the previous five years, as certified
by the Soil Association, or other
equivalent body.
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2.62.3 (A)
The source of imported topsoil should, as far as can be
ascertained, be free of chemical contaminants and of banned or
controlled weeds.
2.63 IMPORTED TURF
(i) For in-situ turf for relaying, see
Clauses 3.2 and 3.9.
(ii) BS 3969:1998 Clause 3 permits
up to 50% of Dwarf Leafy Perennial
Ryegrass.
1. Imported turf shall comply with BS 3969 and be delivered to the Site within 24
hours of lifting (18 hours in spring and summer). Constituent grasses and their
proportions shall comply with the provisions of BS 3969:1998, Clause 3.
2.64 INDUSTRIAL FLOORING, WALKWAYS AND STAIR TREADS
(i) The information required by
Clause 4 of the relevant Part of BS
4592 should be described in the
Contract.
1. Open type and plate flooring shall comply with BS 4592-0 and the relevant part
of BS 4592, set out in the table below:
(ii) BS EN ISO 14122-2 and BS EN
ISO 14122-3 give guidance on the
construction of walkways and
stairs.
Material and Type
(iii) The weight of galvanising
should be described in the Contract
to suit the resistance to the
corrosiveness encountered. BS EN
ISO
14713-1
gives
coating
thickness/weight
for
typical
environment classifications.
(iv) Cut openings and edges of
open type floor panels should be
resealed to prevent water ingress.
All straight edges, and where the
shape allows, should be fully and
neatly trimmed with a full depth
binding-bar.
(v) Reference should be made to
the Manual Handling Operations
Regulations.
Yorkshire Water
additional, new
clauses
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or substitute
BS 4592 Part
Metal open bar
1
Expanded metal
2
Cold formed metal planks
3
GRP open bar
4
Metal and GRP solid plates
5
Moulded GRP open mesh
6
2. After manufacture mild steel flooring, walkways and stair treads shall be hot
dip galvanised, in accordance with BS EN ISO 1461.
3. Individual floor panels shall be bolted down to prevent unauthorised removal
and shall be prevented from sliding sideways when adjacent panels are removed
by means of permanent steelwork or non-removable locating studs. Panels that
require frequent lifting shall be hinged and be readily lifted by one man.
Removable floor panels and support beams shall be stamped with reference
numbers to ensure correct replacement.
4. Where bolting is metallurgically incompatible with the material being fixed, the
contact areas shall be isolated either by painting with an approved silicon sealant
(and allowed to dry before tightening together) or with suitable isolating washers
and sleeves.
2.64.5 (A)
Industrial open type metal flooring panels shall be manufactured
so that when fitted the load bearing bars and transverse bars are
aligned with adjacent panels where possible.
2.64.6 (A)
Where contact with water under preparation or conveyance for
public water supply occurs only solid stainless steel flooring,
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walkways, stair treads and platforms shall be used, complying
with clause 2.1 of this specification. The stainless steel shall be
Grade 1.4401 and comply with the British Standards as detailed
in the table in YWS Eng Specification Section 04 Mechanical.
2.64.7 (A)
Panels and support beams shall be stamped with a reference to
allow correct placement.
2.65 JOINERY TIMBER
1. Timber for joinery shall comply with the relevant provisions of BS EN 942.
2. The sizes of sawn and processed softwood and hardwoods shall comply with
the relevant provisions of BS EN 1313-1 and BS EN 1313-2, respectively.
2.66 JOINT FILLER BOARD
1. Filler board for joints in concrete (other than softwood) shall comply with the
requirements and tests in Clause 1015 of the ‘Specification for Highway Works’.
Knot-free softwood, preserved in accordance with Clause 2.126, may be used
for joints in concrete carriageways.
2. Holes in preformed joint filler to accommodate dowel bars shall be accurately
bored or punched out to produce a sliding fit on the dowel bars.
3. The material comprising the joint filler shall be of such quality that it can be
satisfactorily installed in position at the joint.
4. Adhesives used to retain preformed joint fillers in place during construction
shall have no harmful effects on concrete and, except for those used in
connection with softwood fillers, shall be obtained from the same manufacturer
as the joint filler.
5. Preformed filler for joints in structures to retain aqueous liquids shall have a
maximum water absorption of 0.3% by volume and a non-recovered
compression set of 20% of the original thickness, both when tested in
accordance with ASTM D3575-08.
2.67 JOINT SEALING COMPOUNDS AND SEALANTS
(i) Fuel-resistant types of sealants
to BS EN 14188-1 or BS 5212-1
may be required where concrete
surfaces are subject to regular fuel
spillage.
(ii) There are no current British
Standards for the cold-applied,
non-curing and heat-softened,
hand-applied types of sealant,
though various such materials are
available in proprietary form.
1. Joint sealing compounds shall be impermeable ductile materials of a type
suitable for the conditions of exposure in which they are to be placed and
capable of providing a durable, flexible and watertight seal by adhesion to the
concrete throughout the range of joint movement.
2. Hot poured joint sealants shall comply with BS EN 14188-1 Type N1 sealant.
3. Cold poured polymer-based joint sealants shall comply with BS 5212-1
Normal Type N sealant.
4. Primers for use with joint sealants shall be compatible with, and obtained from
the same manufacturer as, the adjacent sealant. Primers shall have no harmful
effects on concrete.
(iii) BS 6213 gives guidance on the
selection of constructional sealants.
5. Sealants and primers which will be in contact with sewage or sewage sludge
shall be resistant to biodegradation.
(iv) In certain circumstances,
polyurethane-based sealants (for
which there are no current British
Standards) may be more resistant
to biodegradation than polysulphide-based ones.
6. Two-part polyurethane joint sealants shall comply with the requirements of BS
EN ISO 11600.
(v) CIRIA Technical Notes TN128
and TN144 deal with civil
engineering sealants in wet
conditions.
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2.68 JOINT SEALS AND LUBRICANTS
(i) BS EN 681-1 does not contain a
microbiological test requirement for
elastomeric seals.
1. Elastomeric joint seals shall be obtained from the pipe manufacturers and
shall comply with the provisions of BS EN 681-1. For water mains, the seals shall
be Type WA and for drainage purposes they shall be either Type WC or WG.
2. Seals shall be tested in accordance with BS 7874 and shall comply with the
following:
•
the average loss in mass (Z) of the test pieces shall not exceed 3.5%;
and
•
there shall be no greater release of carbon black or other fillers from the
test set than from the control set when the surface of the specimens is
lightly rubbed.
In the case of composite seals, the requirements apply only to those components
exposed to the contents of the pipeline or pipework.
3. Joint lubricants for sliding joints shall have no deleterious effects on either the
joint rings or pipes and shall be unaffected by the liquid to be conveyed.
Lubricants to be used for jointing water mains shall not impart to water, taste,
colour or any effect known to be injurious to health, and shall be resistant to
bacterial growth.
2.69 JOIST HANGERS
(i) The material and protection
requirements shall be selected from
BS EN 845-1:2003 Table A.1 and
stated in the Contract.
1. Joist hangers for building into masonry walls or the inner skin of cavity walls
shall comply with the provisions of BS EN 845-1.
2.70 LADDERS
(i) BS EN ISO 14122-4 gives
guidance on the construction of
ladders.
1. Ladders, other than those in manholes, shall conform to BS 4211. Ladders in
manholes shall conform to BS EN 14396 with width of rung of 400 mm and two
stringers.
(ii) The weight of the galvanising
should be described in the Contract
to suit the resistance to the
corrosiveness encountered. BS EN
ISO
14713-1
gives
coating
thickness/weight
for
typical
environment classification.
2. Mild steel ladders for vertical fixing shall be fabricated from steel conforming
to BS EN 10025-2. After fabrication, low carbon steel ladders shall be hot dip
galvanised in accordance with BS EN ISO 1461.
3. Stainless steel ladders for vertical fixing shall be fabricated from Grade
X5CrNiMo 17-12-2 steel conforming to BS EN 10088-3.
4. Aluminium ladders for vertical fixing shall be fabricated from Grade EN AW6082 aluminium conforming to BS EN 573-3. After fabrication they shall be
anodised in accordance with BS EN ISO 7599 Grade AA25.
5. GRP ladders shall be manufactured from pultruded sections conforming to BS
EN 13706-2 and BS EN 13706-3. The surface shall be smooth with fibres
embedded and sealed against penetration from dirt and water. The Barcol
hardness of the sections shall be at least 35 when tested in accordance with BS
2782-10.
Yorkshire Water
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clauses
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2.70.6 (A)
After fabrication, aluminium ladders shall be anodised in
accordance with BS EN ISO 7599:2010 Grade AA25
2.70 7 (A)
Rungs shall be welded to the stringers and shall be non-slip.
Safety hoops shall either be bolted or welded to the stringers.
2.70.8 (A)
Access openings from platforms, walkways shall be protected by
hinged gates and not chains. Gates shall be inward opening and
self-closing.
2.70.9 (A)
Where contact with water under preparation or conveyance for
public water supply occurs only stainless steel ladders complying
with Clause 2.1 of this specification shall be used.
2.70.10 (A)
There is a hierarchy regarding access systems. Reference should
be made to YW Safeguard database, Workplace (Health, Safety
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& Welfare) Regulations 1992 and YWS Decking, Handrailing and
Supports (and Access) Asset Standard.
2.71 LEAD
1. The chemical composition of all lead to be used for jointing or caulking shall
comply with the provisions of BS EN 12588.
2. Lead wool shall be extruded to produce strands of triangular cross-section.
2.72 LIME FOR MORTAR
1. Lime for mortar shall be in the form of lime putty, complying with the relevant
provisions of BS EN 459-1.
2.73 LINTELS
(i) The required type and size of
lintel should be described in the
Contract.
1. Concrete, steel or timber prefabricated lintels shall comply with the relevant
provisions of BS EN 845-2.
(ii) BS 5977-1 gives a method for
assessment of the load carried by
lintels in masonry.
2.74 MANHOLE COVERS AND FRAMES
(i) The shape and size of the
opening should be described in the
Contract.
1. Manhole covers and frames shall comply with the relevant provisions of
BS EN 124, BS 7903 and the Highway Agency’s ‘Chamber Tops and Gully Tops
for Road Drainage and Services: Installation and Maintenance’ HA 104/09.
(ii) The Contract should indicate
any requirements for locking
devices.
2. All manhole covers shall have closed keyways.
3. Chamber access covers with a clear opening exceeding 1 m shall conform to
BS 9124.
(iii)
The
responsibilities
for
supplying manhole lifting keys
should be detailed in the Contract.
(iv) BS EN 124 is a minimum
performance standard only.
(v) The maximum weight of
components of covers should be
specified in the Contract. The
specifier should have regard to the
Manual
Handling
Operations
Regulations.
(vi) Covers and frames should be
described in the Contract.
(vii) Covers and frames to
manholes containing air valves on
water mains should be of a
ventilated type.
(viii) The information required by BS
9124:2008 Annex A should be
stated in the Contract.
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2.74.4 (A)
CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
All standard manhole details should show 600 x 600mm
‘Yorkshire Water’ badged manhole cover and frames for all
manhole surface access points. Covers and frames with minimum
clear openings outside the ranges in BS EN124 shall comply with
the provisions of that Standard where applicable. All manhole
covers shall have large keyways and prising slots in accordance
with BS 5834.
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2.74.5 (A)
Standard inspection chamber details should show 600 x 450mm
cover and frames for surface access points.
2.74.6 (A)
All fabricated steel access covers outside the scope of BS EN 124
shall comply with the requirements of BS 9124.
2.75 MANHOLE STEPS
(i) For all manholes, the size and
spacings and type of manhole steps
should be described in the
Contract.
1. Steps for manholes and other chambers shall be Type D Class 1, complying
with the requirements of BS EN 13101.
(ii) Unprotected aluminium steps
should not be used.
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2.75.2 (A)
All standard manhole details should show single double width
step irons as the means for access for man entry.
2.75.3 (A)
Standard manhole details for manholes over 6m depth should
show a secondary surface access point located over the main
sewer channel. This access point to be used for the delivery and
removal of materials and equipment only. The other access to be
in line with the step irons for man entry and the intermediate
landings to be arranged with access holes directly beneath each
other and the surface opening to facilitate the use of a man riding
winch.
2.75.4 (A)
The use of ladders and/or non 600 x 600mm manhole covers and
frames to be classed as non-standard and will only be considered
if warranted by a specific Site need.
2.76 MARKER TAPE AND MARKER POSTS
(i) Consideration should be given to
the use of a marker tape and any
requirements described in the
Contract.
1. Marker tape for buried water mains shall be blue PVC or polyethylene ribbon
at least 150 mm wide, incorporating a corrosion-resistant tracing system and
shall be printed with the words “WATER MAIN” in bold capital letters throughout
its length and at intervals not exceeding 700 mm.
(ii) In the case of fire hydrants, the
requirements of the Fire Authority
should be established and included
in the Contract.
2. Marker tape for buried cables shall be yellow PVC or polyethylene ribbon at
least 150 mm wide and shall be printed with the words “ELECTRIC CABLE” in
bold capital letters throughout its length and at intervals not exceeding 700 mm.
(iii) Appropriate marker tapes for
other buried services, such as fibreoptic cables, should be described in
the Contract.
(iv) Polyethylene mesh should only
be used as a tracing system, and
placed beneath the pipework to
reduce the risk of future damage to
the mesh from excavation.
(v) Where other types of material for
marker posts are required, details
should be given in the Contract.
Yorkshire Water
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3. Marker tape for buried wastewater pipes or pumping mains shall be red PVC
or heavy gauge polyethylene sheeting at least 150 mm wide and shall be printed
with the words “GRAVITY SEWER” or “PRESSURE SEWER” in bold capital
letters throughout its length and at intervals not exceeding 700 mm and shall
incorporate a corrosion-resistant tracing system for non-metallic pipes.
4. Valve or pipeline marker posts shall be precast reinforced concrete 1120 mm
high. The tops of marker posts shall be fixed so that their finished level is 500–
600 mm above the final surface.
5. Marker posts shall be fitted with a 180 x 205 mm indicator plate to indicate
WO, SV, AV or FH, as appropriate, together with main size and distance from
post. Plates shall comply with BS 3251 and shall be fixed to the post with
stainless steel fixings.
6. The colour for fire hydrant plates shall be in accordance with BS 3251 (black
letters on a yellow background).
2.76.7 (A)
Hydrant and valve indicator posts shall be nominally 250mm x
75mm x 1350mm made in concrete. Pipeline field edge marker
posts shall be triangular concrete (approximately 100mm) with
the words ‘WATER’ cast in each face.
2.76.8 (A)
Indicator plates shall be 180mm x 208mm x 3mm with 12mm
radius corners Ref. BS 3251. Fire hydrant plates shall be
weatherproof and printed black on yellow on clear unbreakable
polycarbonate complete with 4 fixing slots (6mm x 22mm). Upper
windows 73mm x 28mm. Lower windows divided into 3, each
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24mm x 28mm. Bottom edge of plate shows 9 windows each
14mm x 14mm. Adhesive numerals shall be used. All other
fittings, sluice valve, air valve, washout and meter, same
description but black on.
2.77 MASTIC ASPHALT
(i) Grade IV mastic asphalt flooring
is suitable for loading sheds and
heavy duty factory floors. Lower
grades may be appropriate in other
circumstances.
(ii) Mastic asphalts with natural rock
asphalt
aggregates
are
not
normally necessary.
(iii) Where an acidic environment is
expected, the Mastic Asphalt
Council
(www.masticasphaltcouncil.co.uk)
should be consulted for advice on
suitability of limestone aggregates.
1. Mastic asphalt for building and civil engineering shall comply with the relevant
provisions of BS 6925:1988 Table 25, as set out below:
Application
Type
Roofing
R988
Flooring
F1076, Grade IV
Tanking
T1097
Coloured flooring
F1451, Grade IV
2.78 MECHANICAL COUPLINGS FOR PIPELINES AND FITTINGS
(i) On potable water pipelines, it
should be noted that all mechanical
couplings and fittings are regarded
as being in contact with potable
water, see Clause 2.1.
1. Mechanical couplings and repair clamps for iron pipes shall comply with WIS
4-21-02.
(ii) The Contract should indicate the
pressure ratings required.
2. Mechanical joints and fittings for polyethylene pipes in nominal size 90 mm to
1000mm for use with cold potable water shall comply with WIS 4-24-01.
Mechanical joints and fittings for polyethylene pipes less than or equal to nominal
size below 63 mm for use with cold potable water shall comply with WIS 4-3211 or BS EN 1254-3.
(iii) The type of end loading restraint
should be described in the
Contract.
3. Fittings for PE80 (MDPE) and PE100 (HDPE) shall be Type 2, fit for the
purpose, end load restraining (except for unusual locations) and have an internal
pipe support.
(iv) IGN 4-52-02 provides guidance
on
polymeric
anti-corrosion
(barrier) coatings and complements
WIS 4-52-01.
4. All fittings shall be protected against corrosion by the application of a
polymeric barrier coating in accordance with WIS 4-52-01. All internal and
external surfaces shall be coated to Class B as a minimum.
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2.78.1 (S)
All repair and connection fittings including those for use on with
PE pipe shall comply with the requirements BS 8561. Mechanical
joints and fittings for polyethylene pipes less than or equal to
nominal size below 63mm for use with cold potable water shall
comply with WIS 4-32-11 or BS EN 1254-3.
2.78.2 (S)
Under pressure connections to PE mains shall not be made using
under pressure tees with mechanical sealing systems, these
connections shall be undertaken using electrofusion branch
saddles with the welding undertaken by suitably qualified
operators and in compliance with WIS 4-32-08. Where this is not
possible or practical then the main shall be shut down and a
normal tee inserted with mechanical couplings.
2.78.3 (S)
All repairs or connections to PE pipe spigot ends shall be made
using mechanical sealing fittings, electrofusion welding shall not
be used in these circumstances. Type 2 fittings for PE pipe shall
be the minimum used and shall, where required, include pipe end
internal supports.
2.78.6 (A)
All joints, seals and lubricants within couplings shall comply with
Clause 2.68.
2.78.7 (A)
The minimum pressure rating of dedicated couplings and flange
adaptors manufactured for a specific pipe material and/or size,
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5. All fasteners shall be protected from corrosion by the application of zinc and
a polymeric barrier coating in accordance with WIS 4-52-03.
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shall be that of the maximum operating pressure of the pipe or its
integral jointing system, whichever is the lesser.
2.78.8 (A)
For wide tolerance couplings and flange adaptors designed to
adapt to a range of pipe materials/sizes the pressure rating shall
be a minimum of 16 Bar.
2.78.9 (A)
Repair clamps and under pressure tees shall have a minimum
pressure rating of 16 Bar.
2.78.10 (A)
Couplings or flange adaptors shall be installed where removing of
plant for maintenance is required. Uniflanges are only permitted
for static applications where the degree of maintainability is low.
2.78.11 (A)
Mechanical under pressure tees u.t.i. DN 300mm shall be Class
A according to BS 8561, for DN >=350mm they shall also be
Class A except where the diameter of the pipe coupon to be
removed to make the connection is less than 40% of the host pipe
diameter when Class B under pressure tees may be used.
2.78.12 (A)
Where mechanical couplings without integrated restraint are
fitted, adequate provision shall be included at valves, tees, bends,
tapers, blank flanges and the like to restrain the pipe system from
movement caused by internal pressures or other reasons. Such
provision shall include anchors, ties, thrust blocks or other
restraints as necessary.
2.78.13 (A)
Fittings for PE80(MDPE) and PE100 (HPPE) shall be a minimum
of Type 2 rated with internal pipe support provided where required
by manufacturer’s instructions for the pressure rating and pipe
SDR/material. And where installation conditions require or
instructed by the Employer they shall be Type1 rated with full
internal pipe support.
2.78.14 (A)
For dedicated couplings and flange adaptors manufactured for a
specific material and size, the pressure rating shall be that of the
maximum operating pressure of the pipe or its integral jointing
system, whichever is the lesser.
2.78.15 (A)
The installation of mains repair or connection fittings (e.g. under
pressure tees) on certain existing pipe material e.g. PVC, A.C.
GRP shall only be undertaken in accordance with the fittings
manufacturer’s instructions regarding fitting compatibility with the
pipe materials and any specific bolt torque requirements for that
installation.
2.78.16 (A)
Under-pressure tees shall be designed to take the loadings and
stresses generated by drilling and cutting without affecting their
structural integrity or sealing characteristics.
2.78.17 (A)
Prior to fitting mechanical couplings to polyethylene pipes of
300mm or greater heating mats will be used to ‘soften’ the pipe to
ensure that the coupling grips sufficiently.
2.79 METAL LATHING
1. Expanded metal and ribbed lathing for internal plastering and external
rendering, shall comply with the relevant provisions of BS EN 13658-1 and BS
EN 13658-2, respectively.
2.80 METAL TIES
(i) British Standard DD 140 gives
recommendations for the design of
wall ties.
1. Metal ties for cavity wall construction shall comply with the relevant provisions
of BS EN 845-1.
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Metal ties shall be manufactured from stainless steel.
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2.81 MINERAL AGGREGATES FOR FLAT ROOFS
(i) Where an acidic environment is
expected, the Mastic Asphalt
Council
(www.masticasphaltcouncil.co.uk)
should be consulted for advice on
suitability of limestone aggregates.
1. Mineral aggregates for the reflection of solar heat on flat built-up bitumen or
mastic asphalt roofs shall be light coloured and consist of a hard limestone
having a low moisture absorption characteristic, granite, gravel, calcined flint,
calcite or felspar of 10 mm nominal size.
2.82 MORTAR
1. Mortar shall be mixed only when required and in the relevant proportions
indicated in Table NA.2 of the UK national annex to BS EN 1996-1-1:2005 until
its colour and consistency are uniform. The constituent materials shall be
accurately gauged, allowance being made for the bulking of fine aggregate.
2. All mortar shall be conveyed fresh as required for use. Mortar which has begun
to set or which has been Site-mixed for a period of more than one hour in the
case of Classes M12 and M6, and two hours in the case of Classes M4 and M2
shall not be used. Plasticising and set-retarding admixtures shall conform to BS
EN 934-3.
3. Ready-mixed and ready-to-use rendering and masonry mortar shall conform
to BS EN 998-1 and BS EN 998-2, respectively.
4. Rapid hardening cementitious, epoxy resin or polyester resin mortar for setting
manhole covers and frames shall have a minimum working time of 15 minutes.
The mortar shall reach a minimum compressive strength of 30 N/mm2 and
minimum tensile strength of 5 N/mm2 within 3 hours of mixing.
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2.82.5 (A)
Pigments for mortars shall comply with BS EN 12878.
2.82.6 (A)
Mixes for mortar products shall contain sulphate-resisting
Portland cement to BS 4027.
2.82.7 (A)
Where bedding mortar is to be used between any chamber
section and the manhole cover, inspection cover or surface box
frame, then this shall be one of the resin based bedding mortars
with the minimum properties as defined in 2.82.4
2.83 NAILS
1. Nails shall comply with the relevant provisions of the appropriate Standard, as
set out below:
Type
Standard
Steel
BS 1202-1
Copper
BS 1202-2
Aluminium
BS 1202-3
2.84 NATURAL STONE
1. Natural stone shall be of durable quality, uniform in texture, and free from iron
bands, spots, sandholes, flaws, shakes and other imperfections which would
adversely affect its strength or appearance. The dimensions of stones shall be
adequate for proper coursing and bonding.
2.85 NON-MAN ACCESS CHAMBERS
1. Non-man access chambers shall comply with the relevant provisions of BS
EN 752.
2.86 NUTS, SCREWS, WASHERS AND BOLTS
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(i) Any protective coatings required
should be described in the
Contract.
(ii) The type of nuts, screws,
washers and bolts required should
be described in the Contract.
(iii) The specific environmental
conditions on Site would determine
the grade of the material required.
Section 2 - Materials
1. Nuts, screws, washers and bolts shall comply with the relevant provisions of
the appropriate Standard, as set out below:
Type
Standard
Metal washers for general purposes
BS 4320
ISO black bolts, screws and nuts
BS 4190
ISO precision bolts, screws and nuts
BS 3692
High-strength friction grip bolts, nuts
and washers
BS 4395-1 or relevant parts of BS
EN 14399
Stainless steel bolts, screws, studs
BS EN ISO 3506-1
Stainless steel nuts
BS EN ISO 3506-2
2. Bolting for pipes and fittings shall comply with the relevant provisions of BS
EN 1092-2, except that spheroidal graphite iron bolts for use with ductile iron
pipes and fittings shall be manufactured from metal complying with the
provisions of BS EN 1563 for Grade EN-JS1050.
3. Bolt length and tightening torque shall be in accordance with manufacturer’s
recommendations and shall be sufficient to ensure that nuts are full-threaded
when tightened in their final position with two threads showing.
4. Where bolting is metallurgically incompatible with the material being fixed, the
contact areas shall be isolated either by painting with an approved silicon sealant
(and allowed to dry before tightening together) or with suitable isolating washers
and sleeves.
5. Washers shall be provided under the head of the bolt and under the nut.
6. Unless manufactured of stainless steel, all fasteners shall be protected against
corrosion in accordance with WIS 4-52-03.
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2.86.7 (A)
Sherardizing in accordance with BS EN ISO 14713-3 and a resin
coating shall be the preferred method of corrosion protection.
This requirement applies to pipelines for both above and below
ground use and within protective structures.
2.86.8 (A)
Bolt sets which are submerged or part submerged shall be made
of stainless steel Grade 316S31 complying with BS EN 10083,
BS EN 10084, BS EN 10085, BS EN 10087, BS EN 10098 BS EN
10250, PD 970 or BS 1449.
Those required or designed to be tightened, released or adjusted
during the maintenance of the plant, or for anchoring of plant or
services to walls or foundations shall be stainless steel.
2.86.9 (A)
Bolting shall be compatible with the material being fixed and in
compliance with Clause 2.146.
2.86.10 (A)
Nuts, screws, washers and bolts in contact with water under
preparation or conveyance for public water supply shall be
stainless steel.
2.86.11 (A)
Zinc plating alone is not acceptable as a means of corrosion
protection for fasteners utilised on buried joint applications or
damp/saline environments.
2.86.12 (A)
The grades of hardness of stainless steel used in bolt sets shall
be such as to avoid seizing problems. An anti-seize lubricant shall
be used that complies with Clause 2.1
2.86.13 (A)
The minimum grade for mild steel nuts, screws, bolts and washers
shall be Grade 8.8. Nuts, bolts, screw and washers shall be of a
sufficient grade to ensure that the required torque does not
exceed 70% of the bolts yield strength. Where there is any doubt
the higher bolt grade shall be used.
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Section 2 - Materials
2.87 PACKINGS FOR TUNNELS
1. Packing pieces for joint gaps in bolted tunnel segments shall be band-sawn,
knot-free softwood, preserved in accordance with Clause 2.126.
2.88 PAINTS AND PAINTING MATERIALS FOR BUILDINGS
(i) This Clause applies to paint work
to BS 6150 - see Clause 6.26.
1. Ready-mixed paints for buildings shall be of external quality. Paint colours for
building purposes shall comply with the relevant provisions of BS 4800.
(ii) The required type of priming
paint should be described in the
Contract.
2. Raw, refined and boiled linseed oils for paints and varnishes shall comply with
the relevant provisions of BS EN ISO 150.
(iii) Paints for the protection of
steelwork against corrosion and
paints for the fire protection of
steelwork should be described in
the Contract.
3. Knotting for use as an impervious covering for knots and other resinous areas
shall comply with BS 1336.
4. Stopping shall comprise a mixture of one third white lead to two thirds ordinary
whiting and linseed oil putty, with a small quantity of gold size added.
5. Priming paint for wood shall comply with the appropriate Standard, as set out
below:
Type
Standard
Ready-mixed aluminium
BS 4756, Type II
Water-borne
BS 7956, Type B
Solvent-borne
BS 7956, Type B
6. Priming paint for metal shall comply with the relevant provisions of BS 4652.
Lead-based priming paint shall not be used.
7. Paint remover shall be non-flammable, solvent-based and comply with BS
3761.
8. All painting materials for one operation shall be compatible and shall be
obtained from one manufacturer.
Yorkshire Water
additional, new
clauses
Services Ltd
or substitute
2.88.6 (S)
For non decorative painting of metal the primer shall comply with
the relevant provisions of BS 4652. Lead based priming paint
shall not be used.
2.89 PERMANENT FENCING
(i) Where appropriate, the various
Parts of BS 1722 provide for
concrete for surrounding the bases
of posts.
(ii) All timber for permanent fencing
should be given preservative
treatment, in accordance with the
provisions of the relevant Standard.
1. Permanent fencing shall comply with the relevant part of BS 1722, as set out
in the following table:
BS 1722
Type of Fencing
Part 1
Chain link fences
Part 2
Strained wire and wire mesh netting fences
Part 4
Cleft chestnut pale fences
Part 5
Close boarded and wooden palisade fences
Part 7
Wooden post and rail fences
Part 8
Mild steel (low carbon steel) continuous bar fences and
hurdles
Part 9
Mild steel (low carbon steel) fences with round or square
verticals and flat horizontals
Part 10
Anti-intruder fences in chain link and welded mesh
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or substitute
Section 2 - Materials
Part 11
Prefabricated wood panel fences
Part 12
Steel palisade fences
Part 14
Open mesh steel panel fences
2.89.2 (A)
Fencing for security purposes shall comply with the requirements
of S29.
2.90 PIPE SURROUND MATERIALS
(i) Any limitations on the size and
type of materials should be
described in the Contract.
1. Processed granular and as-dug bedding, side fill and surround materials for
buried pipelines shall comply with WIS 4-08-02.
2. Recycled materials shall comply with BS 8500-2.
(ii) IGN 4-08-01 gives guidance on
pipe surround materials.
2.91 PIPES FOR DUCTS
(i) BS 8313 gives guidance on ducts
for building services.
1. Pipes, joints and fittings for exposed ducts for building services shall comply
with the appropriate Standard, as set out below:
(ii) Certain Public Utilities may
require ducts to be of a particular
colour.
Unplasticised PVC pipe
(iii) Grey PVC-U to BS 3506 may be
used where ducts are not required
to be pressure tight.
BS EN ISO 1452- 2 and BS EN
ISO 1452-3 or BS 3506
Hollow steel sections (greater than 150
mm OD)
BS EN 10210-2
Steel tubes (not greater than 150 mm
OD)
BS EN 10296-1 or BS EN 10297-1
Type
Standard
2. Pipes, joints and fittings for buried ducts shall have flexible mechanical joints
and comply with the relevant provisions of the appropriate Standard, as set out
below:
Type
Standard
Vitrified clay
BS 65 or BS EN 295-1
Unreinforced or reinforced concrete
BS EN 1916 and BS 5911-1
Unplasticised PVC
BS 4660 or BS EN 1401-1
Structured wall plastics pipes
BS EN 61386-24
3. All cable ducts shall be fitted with draw cords.
4. Pipes for cable ducts shall be coloured as follows:
Duct
Colour
Electricity power cables
Black
Electrical signal and telecoms cables
Grey
Cable TV
Green
Street Lighting
Orange
Motorway communications
Pink
2.91.3 (S)
CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
All cable ducts shall be compliant with Yorkshire Water
Engineering Specification Section 05 and associated WIMES
Specification clauses. All cable ducts shall be fitted with draw
cords.
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Section 2 - Materials
2.92 PIPES FOR LAND DRAINAGE AND TEMPORARY DRAINS
1. Pipes, joints and fittings for land drainage and temporary drains shall comply
with the relevant provisions of the appropriate Standard, as set out below:
Type
Standard
Vitrified clay
BS 65 or BS EN 295-1
Perforated vitrified clay
BS EN 295-5
Clayware field drains
BS 1196
Plastic field drains
BS 4962
2.93 PLASTER
1. Premixed lightweight plaster shall comply with the relevant provisions of BS
EN 13279-1.
2. Polyvinyl acetate emulsion bonding agents for indoor use shall comply with
BS 5270-1.
2.94 PLASTIC CHAMBERS AND RINGS
1. Plastic chambers and rings, including demarcation chambers, shall comply
with BS EN 13598-1 or BS EN 13598-2.
2.95 PLASTIC SHEETING
1. Plastic sheeting for waterproof underlay shall have a composition in
accordance with BS 6076.
2. The minimum nominal film thickness shall be 250 μm.
2.96 PLYWOOD
(i) The required thickness, grade
and type of bonding should be
described in the Contract.
(ii) Proprietary products are
available for these applications.
1. Plywood for general use shall comply with the relevant provisions of BS EN
636. Marine grade plywood shall be in accordance with BS 1088-1.
2. All plywood used for formwork on water supply structures in temporary and
permanent works on the side of the concrete facing the potable water shall either
be phenol free or be faced with a surfacing that prevents phenol from contacting
the concrete.
3. Interior quality plywood shall have MR bonding and external quality plywood
shall have WBP bonding.
2.97 POLYETHYLENE PIPES AND FITTINGS
(i) For co-extruded polyethylene
pipes, identification stripes may be
included in the blue outer layer .
(ii) The pressure rating should be
described in the Contract.
(iii) Further guidance on the design
and use of PE pipes can be found
in the WRc/BPF ‘Polyethylene Pipe
Systems Manual’ and IGN 4-32-18.
(iv) The required short-term surge
pressure resistance and the lifetime
at a pressure of 1.2 times MRS
(Minimum Required Strength as
defined in BS EN 12201-1) to
determine the safe duration of
1. Polyethylene piping systems for water supply shall comply with BS EN
12201-1 and BS EN 12201-2 and be coloured blue. Co-extruded polyethylene
pipes may be used for water supply but shall have a blue outer layer on top of
blue or black inner layers.
2. Polyethylene piping systems for above-ground pressure systems for general
purposes, for drainage and for sewerage shall comply with BS EN 12201-1 and
BS EN 12201-2 and be coloured black. Co-extruded polyethylene pipes may be
used for these purposes but shall have a black outer layer.
3. Polyethylene fittings for use with cold potable water shall comply with the
relevant provisions of BS EN 12201-3.
4. Electrofusion fittings shall comply with the relevant provisions of BS EN
12201-3.
5. All electrofusion fittings shall be of integral wire construction. All fittings shall
be of an automatic type and fitted with recognition resistors, identifiable by an
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pressure tests should be stated in
the Contract.
Section 2 - Materials
automatic electrofusion control box, complete with an electronic data acquisition
facility for joint data analysis and quality assurance.
(v)
Clause
2.78.2
covers
mechanical joints and fittings for
polyethylene pipes for use with cold
potable water.
(vi) Pipes and cisterns conveying
and holding water that is not potable
should be marked or colour coded
in accordance with BS 1710.
(vii) Black polyethylene pipes with
blue stripes should only used for
water supply if stated in the
contract.
Yorkshire Water
additional, new
clauses
Services Ltd
or substitute
2.97.1 (S)
Replaces all Clauses 1 to 5
Yorkshire Water
additional, new
clauses
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or substitute
2.97.2 (A)
End load resistant mechanical joints and compression fittings
made principally of thermoplastics for MDPE pipes up to nominal
size 63 for water under preparation or conveyance for public
water supply shall comply with the relevant provisions of
WIS 4-32-11.
2.97.3 (A)
When being stored and in order to prevent UV degradation, pipes
shall be stored in accordance with manufacturers’
recommendations. Pipes with scoring or damage of a depth
greater than 10% of the pipe wall thickness shall not be used.
2.97.4 (A)
The use of any polyethylene pipe with Standard Dimensional
Ratio other than 11 or 17, or nonstandard pipe OD’s shall be first
agreed with the Employer in respect of its hydraulic operating
conditions and its installation/burial conditions.
Polyethylene pipe systems for water supply, above ground use
and wastewater water applications shall comply with the relevant
provisions of BSEN 12201 for pipe and fittings.
The Employer shall be consulted regarding availability of repair
kits in Strategic Stores for the pipe dimensions proposed for any
scheme.
Where there is no coverage, then appropriate
mechanical repair components shall be supplied to the
Employer’s Strategic Stores.
2.97.5 (A)
Mechanically sealing under pressure tees shall not be used on
PE mains; such connection shall only be made via electrofusion
branch saddles or via mains cut out and conventional tee
insertion see 2.78.2.
2.97.6 (A)
Mechanical joints and fittings for use with polyethylene pipes for
use with cold potable water shall comply with BS 8561 and have
a minimum end-load resistant performance exceeding Type 2 in
respect of that standard.
2.97.7 (A)
Electrofusion fittings shall have some form of recognition system
(e.g. bar coding/recognition resistors) identifiable by an automatic
electrofusion control box. The use of electrofusion or mechanical
fittings for jointing PE pipe shall be in accordance with the
Employers policy current at that time and WIS 4-32-08.
2.97.8 (A)
Compression fittings of copper and copper alloy for MDPE pipes
up to nominal size 63mm for water under preparation or
conveyance for public water supply shall comply with the relevant
provisions of BS 864: Part 5.
2.98 PRECAST CONCRETE SLABS AND COVER FRAME SEATING RINGS
(i) Additional protective measures
required by BRE Special Digest
No. 1 to provide resistance to the
1. Precast concrete slabs and cover frame seating rings shall comply with the
relevant provisions of BS EN 1917 and BS 5911-3.
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Section 2 - Materials
actual
ACEC
(Aggressive
Chemical
Environment
for
Concrete
class
should
be
described in the Contract.
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additional, new
clauses
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2.98.2 (A)
Clauses 2.26.4 (A) and 2.26.6 (A) shall apply.
2.99 PRECAST CONCRETE FLAGS AND PAVING BLOCKS
1. Precast concrete flags shall be hydraulically pressed and shall comply with
the relevant provisions of BS EN 1339. Flags shall be 50 mm thick.
2. Precast concrete paving blocks shall comply with the relevant provisions of
BS EN 1338.
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additional, new
clauses
Services Ltd
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2.99.3 (A)
Clause 2.26.6 (A) shall apply.
2.100
PRECAST CONCRETE KERBS, CHANNELS, EDGINGS AND
QUADRANTS
1. Precast concrete kerbs, channels and edgings shall be hydraulically pressed,
and they, and precast concrete quadrants, shall comply with BS EN 1340. Where
kerbs or channels are required to be laid to a radius of 12 m or less, components
of the appropriate radius shall be used.
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additional, new
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2.100.2 (A)
Clause 2.26.6 (A) shall apply.
2.101 PRECAST CONCRETE MANHOLES AND SOAKAWAYS
(i) Particular requirements from the
options listed in BS EN 1917 and
BS 5911-3 should be described in
the Contract.
1. Precast concrete manhole and soakaway units of circular cross-section shall
comply with the relevant provisions of BS EN 1917 and BS 5911-3. Units which
bed onto bases shall be manufactured so that imposed vertical loads are
transmitted directly via the full wall thickness of the unit.
(ii) Additional protective measures
required by BRE Special Digest No.
1 to provide resistance to the actual
ACEC
(Aggressive
Chemical
Environment for Concrete) class
should be described in the
Contract.
2. The profiles of joints between units and the underside of slabs shall be capable
of withstanding applied loadings from such slabs and spigot-ended sections shall
only be used where the soffit of the slab is recessed to receive them.
Yorkshire Water
additional, new
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2.101.4 (A)
Services Ltd
or substitute
3. Precast concrete chamber sections for valves and meters shall be interlocking
and comply with BS EN 1917 and BS 5911-3.
Clauses 2.26.4 (A) and 2.26.6 (A) shall apply.
2.102 PRECAST CONCRETE BOX CULVERTS
(i) The design of culverts is detailed
in CIRIA Guide C698.
1. Precast concrete box culverts shall comply with BS EN 14844.
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clauses
2.102.2 (A)
Services Ltd
or substitute
Clause 2.26.4 (A) shall apply.
2.103 PRECAST CONCRETE SEGMENTS FOR TUNNELS AND SHAFTS
(i) The required type of cement
should be described in the
Contract.
(ii) A review of current test
procedures for precast concrete
1. All concrete used in the manufacture of segments shall be compressive
strength class C32/40 as defined in BS 8500-1.
2. Concrete shall be sampled and tested for compliance with the specified
strength class in accordance with the provisions of BS EN 206-1:2013, Clause
8.2.1. The concrete shall be subject to identity checks of not less than one
sample per 20 m3 of fresh concrete. All segments shall have the date of
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tunnel linings can be found in CIRIA
Technical Note TN104.
Section 2 - Materials
manufacture clearly marked in an appropriate position at the time of
manufacture.
3. Segments shall not be removed from the moulds until the concrete cube
strength has reached 10 N/mm2 and no segments shall leave the place of
manufacture or be used until 28 days after casting. Segments shall not be
incorporated until the relevant test results confirm that the concrete complies
with the specified compressive strength class.
4. Segments shall be cast with such accuracy and uniformity of dimensions that
all similar segments shall be interchangeable, not only within individual rings but
with corresponding segments of other rings. All surfaces of the segments shall
be free from cracking, honeycombing or other blemishes.
5. Segments shall be manufactured to the following tolerances:
Nominal Dimension
Permissible Deviation (mm)
Circumferential length
±1.5
Radius of curvature
±3
Thickness
±3 (on back face only)
Width
±1.5
6. Segments shall be designed to have a water absorption not exceeding 6% by
mass when tested in accordance with BS EN 1917.
7. Segments shall withstand handling, erection and any shield thrust stresses,
without cracking, spalling or distortion.
8. The clear cover of concrete over any steel reinforcement shall be not less than
12 mm and spacers shall be of corrosion-resistant material.
9. All segment joint faces shall have a caulking rebate of minimum size 20 mm
deep by 3 mm wide for bolted segments and 10 mm deep by 3 mm wide for
smooth-bore segments.
10. Where grouting is described in the Contract, all segments shall have at least
one grout hole of 50 mm diameter.
11. Tapered segments for curves shall comply with the general requirements of
this Clause, each segment having the radius and the location of the segment
within the ring, clearly marked. Segments shall be symmetrically tapered.
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additional, new
clauses
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2.103.12 (A)
Clause 2.26.4 (A) shall apply.
2.104 PRECAST CONCRETE SETTING BLOCKS FOR PIPES
1. Precast setting blocks for pipes shall have rectangular faces, with sufficient
plan area to prevent punching of the blinding concrete or final surface, and to
provide an adequate seating for the pipes. They shall be manufactured from
compressive strength C16/20 concrete using the same type of cement as in the
adjacent concrete bed. Blocks shall not be used until they have achieved a cube
strength of 13.5 N/mm2.
2.105 PRECAST CONCRETE TANKS
(i) BS EN 1992-3 covers the design
and construction of structures used
for retaining aqueous liquids. Its
scope includes precast concrete.
(ii) The type of seal (WA, WB, WC,
WD, etc.) should be described in
the Contract.
1. The design and construction of concrete panels for pre-cast concrete tanks
shall comply with BS EN 1992-3.
2. Rubber and thermoplastics seals between panels, floor slabs, etc., shall
comply with BS EN 681-1 and BS EN 681-2, respectively.
3. Class C32/40 concrete shall be used as a minimum for the concrete panels.
(iii) The required exposure class of
concrete should be stated in the
Contract.
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Section 2 - Materials
2.105.4 (A)
Clauses 2.26.4 (A) and 2.26.6 (A) shall apply.
2.106 PRESTRESSED CONCRETE PIPES AND FITTINGS
(i) Particular requirements from the
options listed in BS EN 639, BS EN
642 or BS 5911-5 should be
described in the Contract.
1. Prestressed concrete pressure pipes and fittings shall comply with the relevant
provisions of BS EN 639, and BS EN 642. Prestressed concrete pipes and
fittings for drainage and sewerage purposes shall comply with the relevant
provisions of BS 5911-5.
(ii) The Contract should describe
whether cylinder or non-cylinder
type pipes and fittings are required.
2. Unless steam cured, no pipes or fittings shall leave the place of manufacture
until they have been allowed to cure and mature under suitable conditions for a
total period of not less than 28 days.
Yorkshire Water
additional, new
clauses
2.106.3 (A)
Prestressed concrete pipes and fittings shall not be utilised for
buried pressurised water pipelines without the express consent of
the Employer.
2.106.4 (A)
Clauses 2.26.4 (A) and 2.26.6 (A) shall apply.
Services Ltd
or substitute
2.107 PRESTRESSED PRECAST CONCRETE FLOORS
1. Precast prestressed concrete floors shall be formed from units manufactured
to BS EN 13369.
2.108 PROFILED STEEL SHEETING
(i) Details of profiled steel sheeting
should be described in the
Contract.
1. Profiled steel sheeting and cladding shall comply with BS EN 14782.
2.109 PROPYLENE CO-POLYMER PRESSURE PIPES
1. Propylene co-polymer pressure pipe shall comply with the relevant provisions
of BS 4991 and, where it is to be in contact with potable water, shall be Series
1.
2.110 PTFE TAPE
1. Unsintered polytetrafluoroethylene (PTFE) tape for thread sealing applications
shall comply with BS 7786.
2.111 PULVERISED-FUEL ASH
1. Pulverised-fuel ash (PFA) and fly ash, for use as a component material in
cementitious grout or non-structural concrete, shall comply with BS 3892-2 and
BS 3892-3.
2. PFA for use as a cementitious component in structural concrete and annulus
grouts shall comply with BS EN 450-1 fineness category S, loss on ignition
category A or B. PFA for annulus grouts shall be pre-blended and bagged before
delivery to the Site.
3. Conditioned PFA or fly ash for use as a fill material shall be supplied dry and
shall be compacted to ± 2% of the optimum moisture content and maximum dry
density in the ranges 18-25% and 1200-1500 kg/m3, respectively, when
determined in accordance with BS 1377-4 (light or heavy Hammer Method rather
than Rammer Method). The PFA fill shall not be reused when producing the
compaction curve.
Yorkshire Water
additional, new
clauses
Services Ltd
or substitute
2.111.4 (A)
Each consignment of fly ash delivered to the concrete production
plant for use in concrete shall be accompanied by a certificate of
compliance with BS EN 450-1.
2.111.5 (A)
Fly ash for use as a component material in cementitious grout or
non-structural concrete shall comply with BS EN 450-1.
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Section 2 - Materials
2.111.6 (A)
In reference to its use in concrete, the term “fly ash” is used to refer
to essentially the same material as previously known as “pfa” but
which complies with BS EN 450-1.
2.112 RAINWATER PIPES AND GUTTERS
(i) The Contract should describe the
section required for aluminium and
PVC-U gutters.
(ii) The Contract should describe
the required grade and shape of
sheet and strip aluminium pipes
and gutters.
1. Rainwater pipes, gutters, fixings and accessories shall comply with the
relevant provisions of the appropriate Standard, as set out below:
Material
Standard
Cast iron
BS 460
Aluminium
BS EN 612
(iii) BS EN 877 deals with flexible
joints for cast iron drainpipes and
fittings.
Steel
BS EN 612
PVC-U (gutters)
BS EN 607
(iv) The Contract should describe
whether ears are required on cast
iron pipes and fittings.
PVC-U (downpipes)
BS EN 12200-1
Brackets for gutters to BS EN 607 and
BS EN 612
BS EN 1462
(v) The Contract should describe
the required colour of PVC-U pipes
and fittings.
2.113 ROLLED ASPHALT
1. Hot rolled asphalt shall comply with the relevant provisions of BS EN 131084.
2.114 ROOF COVERINGS
(i) The required type, grade,
category, classification, size, group
or colour of roof covering material
should be described in the
Contract.
1. Roof coverings shall comply with the relevant provisions of the appropriate
Standard, as set out in the following Table:
Material/Type
Standard
Clay tiles and fittings
BS EN 1304
Concrete tiles and fittings
BS EN 490
Slates
BS EN 12326-1
Felt
BS EN 13707
2.115 SAFETY CHAINS IN SEWERS
1. Mild steel safety chain shall be medium tolerance chain conforming to BS EN
818-3 Grade 4 nominal size 8 x 24. After manufacture, mild steel safety chains
shall be hot dip galvanised in accordance with BS EN ISO 1461.
2. Stainless steel safety chain shall be manufactured from Grade X5CrNiMo 1712-2 steel conforming to BS EN 10088-3. Chain links shall be welded and have
an internal length not exceeding 45 mm and an internal width of between 12 mm
and 18 mm. The fins caused by welding shall be removed and the weld shall be
smoothly finished all round.
3. The chain shall have a breaking force of 30 kN and a proof force of 15 kN
when tested in accordance with BS EN 818-1.
4. Anchor bolts for fixing safety chains shall be of the stainless steel safety type
which provides a progressive mode of failure.
2.116 SAMPLE TAPS
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(i) Taps should be specifically
designed for sampling such as
chrome-plated gunmetal with a
tapered spout and protective cover,
commonly referred to as the “Harris
Tap”.
(ii) Single non-rising spindle
headworks tap to BS EN 200 with
the flow straightener or aerator
removed may suitable for this
purpose.
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Section 2 - Materials
1. Sample taps shall be metal complying with BS EN 200 or equivalent, without
attachments or inserts.
2. For sample points located externally, the tap shall be enclosed in a lockable,
purpose-designed sample pillar.
3. Taps for sampling purposes shall be a ½” male chrome sample tap, ½” BSP
inlet. They shall be permanently labelled with “Sample Name/Water Quality Site
No./Required Flushing Time”.
2.116.2 (S)
See Section 7.25 for potable water regulatory sample point housing
requirements.
2.116.3 (S)
Taps for potable water sampling purposes shall be a ½” BSP male
(inlet chrome plated bibcock with screwed outlet and flameproof
bottle filling taper nozzle. The body shall be manufactured in DZR
cast brass and fitted with BS1010 Easy clean capstan headwork
valve material CW617EN121651998 (European standard) jumper
washer manufactured in E645/E78 black coloured EPDM rubber
material (WRC LISTING NUMBER 0602514)
2.116.4 (A)
All potable water sample points shall be clearly labelled in the
following format;
Regulatory – Blue background, white lettering
Investigational – White background, blue lettering
The sample location, specific URN, “xx mins flush time” and “For
Sample Use Only” must be included on the label, along with a
detailed schematic of the sample line.
2.117 SANDS
(i) The requirement for sands to be
washed is additional to the
requirements of the Standards but
is in line with the main conclusion of
CIRIA Report R59 ‘Building Sands:
Availability, Usage and Compliance
with Specification Requirements’.
1. Sands for mortar and grout shall comply with BS EN 13139 and
PD 6682-3.
2. Sands for floor screeds shall comply with the relevant provisions of BS EN
12620 and PD 6682-1.
3. Sands for external rendering and internal plastering with lime and Portland
cement shall comply with the relevant provisions of BS EN 13139 and PD 66823.
4. All sands required to comply with BS EN 12620 and PD 6682-1, BS EN 13139
and PD 6682-3 shall be washed sands.
2.118 SEWER LININGS
(i) Appendix A of each WIS, lists
information to be established for
particular design situations.
1. Sewer linings shall comply with the relevant provisions of the appropriate
Standard, as set out in the following Table:
Type
WIS
Glassfibre reinforced cement (GRC)
4-12-04
Precast gunite
4-12-05
Precast and in-situ ferro cement
4-12-06
Polyethylene (PE) pipes (non-pressure
applications)
4-32-05
Glassfibre reinforced plastics (GRP)
4-34-02
Cured-in-place pipe (CIPP)
4-34-04
Polyester resin concrete (PRC)
4-34-05
CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
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2.119 SOIL, WASTE AND VENTILATING PIPES
(i) BS EN 877 deals with flexible
joints for cast iron soil, waste and
ventilating pipes and fittings.
1. Soil, waste and ventilating pipes, fittings and accessories for above-ground
drainage systems shall comply with the relevant provisions of the appropriate
Standard, as set out below:
Material
Standard
Cast iron
BS 416-1 or BS EN 877
PVC-U (soil and ventilating)
BS 1329-1
Polypropylene (waste)
BS EN 1451-1
Plastics (waste)
BS EN 1329-1, BS EN 1455-1, BS EN
1519-1, BS EN 1565-1 and BS EN 15661
2. Wash-basin and sink wastes shall comply with the relevant provisions of BS
EN 274-1.
2.120 STEEL REINFORCEMENT
1. Steel reinforcement shall comply with the relevant provisions of the
appropriate Standard, as set out below:
Type
Standard
Carbon steel bars
BS EN 10080 and BS 4449
Steel wires
BS EN 10080 and BS 4482
Steel fabric
BS EN 10080 and BS 4483
Stainless steel
BS 6744
Epoxy coated steel
BS EN ISO 14654
Bed joint reinforcement for masonry
BS EN 845-3
2. Steel fabric reinforcement shall be welded at the intersections and shall be
delivered in flat sheets, except where pre-bent reinforcement is specified.
3. Steel reinforcement shall be obtained from suppliers holding a valid Certificate
of Approval for the manufacture and/or fabrication of steel reinforcement issued
by the UK Certification Authority for Reinforcing Steels or equivalent authority.
The CARES, or equivalent, Certificate of Approval Number shall be stated on all
appropriate purchase documentation.
Yorkshire Water Services Ltd
additional, new or substitute
clauses
2.120.4 (A)
Reinforcement shall be free from pitting, loose rust, mill scale, paint,
oil grease, adhering earth, ice or any other material that may impair
the bond between the concrete and the reinforcement or cause
disintegration of the concrete.
2.121 STEEL SHEET PILES
(i) The required grade of steel
should be described in the
Contract.
(ii) The requirement for piles to be
coated should be deleted if no part
is to be exposed on completion of
the Works.
1. Steel from which steel sheet piles are rolled shall comply with the relevant
provisions of BS EN 10025-1 and BS EN 10025-2.
2. Maximum rolling margins shall be 4% above and 2.5% below the calculated
masses and 75 mm over and 50 mm under the required lengths.
3. Before being driven, permanent steel sheet piles shall be wire-brushed to
remove loose rust and dirt and be coated with black tar-based paint complying
with BS 1070, Type B, except that piles in contact with water to be used for
potable supply shall be coated with black bitumen solution to BS 3416.
2.122 STILES, BRIDLE GATES AND KISSING GATES
1. Stiles, bridle gates and kissing gates shall comply with the relevant provisions
of BS 5709.
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2. All timber for stiles, bridle gates, kissing gates and posts shall be given
preservative treatment in accordance with the provisions of BS 5709.
3. All fittings and steel stiles, bridle gates, kissing gates and posts shall be hot
dip galvanised in accordance with BS EN ISO 1461.
4. Concrete for surrounding the base of posts shall be compressive strength
class C16/20 (GEN3).
2.123 STRUCTURAL STEEL
1. Structural steel sections shall comply with the relevant provisions of the
appropriate Standard, as set out in the following table:
Type
Standard
Hot-rolled structural steel sections
BS 4-1
Cold-rolled steel sections
BS EN 10162
Hot finished structural hollow steel
sections
BS EN 10210-2
Structural steel angles
BS EN 10056-1
2.124 SURFACE BOXES AND GUARDS
(i) Particular requirements from the
options listed in Appendix A of BS
5834-1 should be described in the
Contract, as should those from
Appendix B of Parts 2 and 3.
(ii) The minimum grade of cover
should be described in the Contract
to suit the vehicle intensity. BS EN
124 describes the minimum grades
suitable for the location of manhole
covers in carriageways, footways
and other locations, e.g., minimum
grade C250 when located within the
kerb area (measured 0.2 m into the
footway/verge and 0.5 m into the
carriageway) and D400 when
located within the carriageway area
(measured 0.5 m from the kerb into
the highway).
(iii) BS 6700 applies to meter boxes
and their installation.
(iv) WIS 4-37-01 covers the
specification of boundary boxes for
the metering and control of
domestic and small industrial water
services.
1. Small and large surface boxes shall comply with the relevant provisions of
BS 5834-2 and BS 5834-3, respectively, or WIS 4-37-01.
2. Small surface boxes having hinged lids shall be provided with hinge pins of a
minimum diameter of 8 mm and made from stainless steel or copper alloy to
prevent corrosion. Other means of retention of surface boxes shall be resistant
to corrosion.
3. Guards and foundation units for underground stop valves shall comply with
the relevant provisions of BS 5834-1 or WIS 4-37-01.
4. Covers for the surface boxes on water mains shall have either the word
“WATER” or the letter “W” cast on the top surface in 75 mm letters, as applicable.
Covers for other applications shall similarly be marked: FH (fire hydrant), WO
(washout hydrant), SV (sluice valve) and AV (air valve).
5. Covers and frames to be installed in carriageway or other areas with frequent
passage of vehicles shall be to the minimum grade stated in BS EN 124 or Grade
A to BS 5834-2.
6. Covers and frames to be installed in all other areas shall be a minimum Grade
of B125 to BS EN 124, or Grade B to BS 5834-2.
7. Precast concrete sections for chambers and base units for buried waterworks
apparatus up to and including 600 x 450 mm clear opening, shall comply with
BS 5834-1 and BS 5834-4. All sections shall be Grade A as defined in that
Standard.
8. Chambers of materials other than precast concrete shall meet the loading
requirements in BS 5834-2.
9. In addition to the requirements of the above, domestic water meter boxes shall
be of the waterproof type and shall contain an integral shut off valve on the
upstream side together with non-return valve. They shall be suitable for use with
concentric type flowmeters. They shall be adjustable for height and slope.
10. Surface boxes and guards providing direct access to areas of potable water
shall be Loss Prevention Council (LPC) security rating 5 compliant.
Yorkshire Water
additional, new
clauses
Services Ltd
or substitute
2.124.6 (S)
CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
Covers and frames installed in all areas to which vehicles may have
access shall be a minimum grade of B125 according to BSEN 124
or Grade B according to BS 5834. In areas where no vehicular
access is possible Grade A15 according to BSEN 124 can be
installed or Grade C according to BS 5834.
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Section 2 - Materials
2.125 SYNTHETIC RESIN ADHESIVES
1. Synthetic resin adhesives for plywood and wood shall be phenolic and
aminoplastic, and comply with the relevant provisions of BS EN 301.
2.126 TIMBER AND PRESERVATION OF TIMBER
(i) See Regulations 8 and 10 of the
Construction (General Provisions)
Regulations 1961, as amended by
the
Construction
(Metrication)
Regulations 1984 for provisions
relating to timber for excavations,
shafts, tunnels and headings.
(ii) The use, class, service factor
and desired life category should be
described in the Contract.
1. All timber in the permanent Works shall be new. Timber for structural use shall
be visually graded GS or SS to BS 4978 with an assigned strength class C16 to
BS EN 1912 or machine graded as strength class C16 to BS EN 338.
2. Blockboards and other laminated woods shall comply with BS EN 12871.
3. Preservative treatment of timber shall be in accordance with BS 8417.
(iii) Consideration should be given
to the use of reclaimed timber and
any provision for its re-use should
be described in the Contract.
(iv) The use of creosote as a
preservative
should
be
discouraged.
Yorkshire Water
additional, new
clauses
Services Ltd
or substitute
2.126.4 (A)
Details of all timber preservation treatments shall be submitted for
approval.
2.127 TREES AND SHRUBS
1. Trees and shrubs shall comply with the relevant provisions of the appropriate
Standard, as set out below:
Type
Standard
Ordinary nursery stock
BS 3936-1
Semi-mature trees
BS 4043
Advanced nursery stock
BS 4043
2.128 TYING WIRE
1. Tying wire for steel reinforcement shall be 1.6 mm diameter, annealed mild
steel wire complying with BS 1052.
Yorkshire Water Services Ltd
additional, new or substitute
clauses
2.128.2 (A)
Where stainless steel reinforcement is to be required, 1mm
stainless steel tying wire shall be used.
2.129 UNPLASTICISED PVC PIPES AND FITTINGS
(i) The colour and size limitation for
PVC pressure pipes are consistent
with the current recommendations
of the National Joint Utilities Group
(NJUG).
(ii) WIS 4-31-08 deals with
molecular oriented PVC-O pipes.
(iii) PVC pipe containing leadbased stabilisers are no longer
1. PVC pressure pipes, joints and fittings shall comply with the relevant
provisions, as set out below:
Material
Pipe
Joints and Fittings
PVC-U (metric blue)
BS EN ISO 1452-2
BS EN ISO 14523
PVC-A
PAS 27
PAS 27
CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
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acceptable under the Water Supply
(Water Quality) Regulations.
Section 2 - Materials
PVC-O
WIS 4-31-08 (12.5 bar
and 16 bar only)
BS EN ISO 14523
2. Pipes for potable water use shall be coloured blue.
3. PVC pipes, joints and fittings for gravity sewers and drains shall comply with
the relevant provisions of BS EN 13598-1, BS 4660 or BS EN 1401-1.
4. Thermoplastics structured wall sewer pipe shall comply with the relevant
provisions of BS EN 13476-1 and WIS 4-35-01 and BS EN 13476-2 or BS EN
13476-3 with the following properties:
1
Maximum length of pipe for laying to be 3 m;
2
Pipe Nominal Short Term Ring Stiffness to be not less than 8 kN/m2;
3
Long term Deformation to be less than 6% of the vertical nominal pipe
diameter;
4
Factor of safety against buckling to be not less than 2.5.
5. Solvent cements for jointing unplasticised PVC pipes shall comply with BS EN
14814. For pipes and fittings complying with BS 4660, BS EN 13598-1 or BS EN
1401-1, solvent cement may alternatively comply with BS EN 14680.
6. Solvent cements for jointing unplasticised PVC pipes shall not be used for
below-ground use.
7. Push-fit joints shall be spigot and socket.
Yorkshire Water
additional, new
clauses
Services Ltd
or substitute
2.129.8 (A)
PVC-U (Metric Blue) pipe and fittings shall not be used for buried
pressure pipeline applications.
2.129.9 (A)
Pipe of a pressure rating less than 10 bar shall not be used
without approval.
2.129.10 (A)
PVC-U (metric blue or imperial grey) pipe and fittings >DN50mm
shall not be used for exposed pressurised pipework applications
regardless of the media carried.
2.130 VALVES AND PENSTOCKS
(i) Particular requirements from the
options listed in the various
Standards should be described in
the Contract.
(ii) BS 6683 deals with
installation and use of valves.
1. Valves and penstocks for pipeline installation shall comply with the relevant
provisions of the appropriate British Standard, as set out below:
the
Type
Standard
Isolating valves for water supply(includes
wedge gate and butterfly)
BS EN 1074-1 and 2
Check/non-return valves for water supply
BS EN 1074-3
Air valves for water supply
BS EN 1074-4
Control valves for water supply
BS EN 1074-5
Industrial butterfly valves
BS EN 593
Penstocks
BS 7775
Cast iron industrial gate valves
BS EN 1171
Cast iron plug valves
BS 5158
(vii) The Contract should indicate
the torque requirements for
operating valves and penstocks.
Cast iron check valves
BS EN 12334
Diaphragm valves – metallic
BS EN 13397
(viii) Wedge or gate valves for water
supply
purposes
should
be
selected with the operational and
Copper alloy globe, globe stop and check
valves
BS 5154
Copper alloy gate valves
BS EN 12288
(iii) Clause 2.135 gives details of
stopvalves.
(iv) BS EN 1092-1 and BS EN
1092-2 deal with flanges.
(v) The method used to control and
operate valves and penstocks
should be described in the
Contract.
(vi)
The
responsibilities
for
supplying turn keys for operating
those valves with caps should be
detailed in the Contract.
CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
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design features described in BS
5163-1 and BS 5163-2.
(ix) On water pipelines, it should be
noted that all fittings are regarded
as
being in contact with potable
water, see Clause 2.1.
2. Valve and penstock parts to be in contact with potable water shall meet the
relevant provisions, as set out below:
Type
Standard
Metallic
DD 256
Non-metallic
BS 6920-1
3. The surfaces of all valves and penstocks shall be protected from corrosion
either by the nature of their material of construction or shall be coated in
accordance with WIS 4-52-01. Internal water wetted surfaces shall be coated to
Class A standard. All other surfaces shall be coated to Class B standard.
4. The direction of closure of all valves shall be agreed with the Water Undertaker
and stated in the Contract. All valves shall have the direction of closing clearly
indicated on the handwheel or body, as appropriate.
Yorkshire Water Services Ltd
additional, new or substitute
clauses
2.130.1 (S)
Replace all Clauses 1 to 4
Refer to YWS Engineering Specification Section 04.24 Valves
2.131 VITREOUS ENAMEL TANKS
(i) The coating type and thickness
should be described in the Contract
to suit the duty requirements.
1. Vitreous enamel (glass fused) steel tanks shall comply with WIS 4-25-01.
2. Vitreous enamel tanks shall be designed and the glass coating selected in
accordance with BS EN ISO 28765.
3. All components used in the construction of a tank shall have a design life of a
minimum of 20 years for the conditions associated with the application,
demonstrated in accordance with BS ISO 15686-2.
4. Each tank panel shall be tested to and conform with BS EN ISO 28765.
5. The tank supplier shall provide certificates for each of the tank panels to
confirm that all have been tested to the appropriate standard detailed in BS EN
ISO 28765 and to confirm that all panels supplied have passed the testing
requirements.
6. Where it is necessary to construct pipework through the tank wall, the tank
supplier shall provide galvanised steel, PN16 flanged connectors, complete with
gaskets, internally and externally, which are compatible with the curvature of the
tank. All cut-outs or sheet penetrations shall be formed in the raw steel sheet
prior to the application of the vitreous enamel coating.
7. Where tanks are to be used for mixing of fluids, the tank shall be designed to
withstand the dynamic loads from mixers and to resist abrasion from material
within the tank contents (e.g., grit). This may take the form of a sacrificial baffle,
or concrete baffle in front of the tank wall.
8. Where man entry into the tank is required at the external ground level, there
shall be an 800 mm minimum clear opening. A bolted man entry hatch shall be
provided unless otherwise stated in the Contract. The high strength low alloy
(HSLA) steel hatch door shall be protected against corrosion to ensure a design
life equivalent to the tank. All manways shall be supplied with davit arms.
9. The tanks should also have a 24 hour static head test (leak test) to check for
leaks. The level of the static head should be comparative to the maximum level
and density of intended use. i.e. a 5 meter sludge head (SD 1.05) should have
a leak test with water to a height of 5.25 meters.
2.132 VITRIFIED CLAY PIPES AND PIPELINE FITTINGS
CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
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(i) IGN 4-11-01 deals with vitrified
clay pipes and fittings.
(ii) The type of joint and jointing
materials for extra chemicallyresistant pipes should be described
in the Contract.
Section 2 - Materials
1. Vitrified clay pipes and pipeline fittings, including extra chemically-resistant
pipes and fittings, shall comply with the relevant provisions of BS 65 or BS EN
295-1.
2. Vitrified clay jacking pipes shall conform to BS EN 295-7.
2.133 WALL TILES
(i) The type, size, thickness and
colour of tiles should be described
in the Contract.
1. Ceramic tiles for internal walls shall comply with the relevant provisions of
BS EN 14411.
2.134 WATER
(i) In certain areas, supplementary
mains carrying non-potable water
have been laid. The use of this
water with cement or in contact with
potable
water
mains
and
installations has been prohibited.
1. Water for use with cementitious materials, or in contact with potable water
mains and installations, shall be of potable quality.
(ii) Where potable water is not
available, then alternative provision
should be detailed in the Contract.
BS EN 1008 gives details of
suitability tests for water for use in
making concrete.
Yorkshire Water
additional, new
clauses
Services Ltd
or substitute
2.134.2 (A)
Recycled water from concrete production may be used in ready
mixed concrete production in accordance with clause5.1.4 of BS
EN 206-1:2013.
2.135 WATER FITTINGS AND APPLIANCES
(i) On potable water pipelines it
should be noted that all fittings are
regarded as being in contact with
potable water, see Clause 2.1.
(ii) Where possible, all fittings and
appliances used as part of the
supply of treated water for domestic
purposes in premises should be
approved by WRAS.
1. Water fittings and appliances shall comply with the relevant provisions of the
appropriate Standard, as set out in the following table:
Water Fitting/Appliance
Type/Material
Standard
Draining taps
Screw-down pattern
BS 2879
Draw-off taps
Metal bodied
(performance)
BS EN 200
Plastics bodied
(performance)
BS EN 200
Above-ground, screwdown pattern
BS 1010-2, BS 5433,
Underground
WIS 4-23-04
Diaphragm type
(copper alloy body)
BS 1212-2
Diaphragm type
(plastics body)
BS 1212-3
Copper
BS 1968
Plastics
BS 2456
Low carbon steel
BS 417-2
Stop valves
Float operated valves
Floats for ball valves
Storage cisterns and lids
CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
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Section 2 - Materials
Thermoplastics
BS 4213
Ceramic
BS 1188
Metal hand rinse
BS EN 111
Glazed fireclay
BS 1206
Stainless steel
BS EN 13310
Horizontal outlet
BS EN 33, BS EN 37
and BS EN 997
WC pans
Plastics
BS 5627
WC seats and covers
Plastics, Type 1
BS 1254
WC flushing cisterns
Dual flush type
BS 1125
Urinals
Stainless steel slab
BS 4880-1
Vitreous china bowl
BS 5520
Automatic flushing
cisterns for urinals
Lidded
BS 1876
Ferrules
Various
WIS 4-22-02
Wash basins
Sinks
WC pans
Connectors for:
2.136 WATERSTOPS
1. Rubber waterstops shall have the following properties:
Property
Test Standard
Requirements
Density
BS ISO 2781
1100 kg/m3 (± 5%)
Hardness
BS ISO 48
60 - 70 IRHD
Tensile Strength
BS ISO 37
Not less than 17.5 N/mm2
Elongation at fracture
BS ISO 37
Not less than 450%
Water absorption
BS ISO 1817
Not
exceeding
5%
(48 hours immersion)
2. Rubber waterstops shall be suitable for storage, handling, installation and
service within a temperature range of 0°C to + 40°C.
3. Hydrophilic expanding waterstops shall have a delay coating to prevent
premature swelling and shall have a minimum expansion of 1 to 3 volumetric
changes. They shall not be used in formed movement joints.
Yorkshire Water
additional, new
clauses
Services Ltd
or substitute
2.136.4 (A)
Junctions shall, where possible, be prefabricated by the
manufacturer. Straight butt joints may be made on Site; the
manufacturer's instructions shall be followed.
2.137 WET-MIX MACADAM
1. Wet-mix macadam shall consist of crushed rock or crushed slag, graded in
accordance with the following table:
CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
BS 410 Test Sieve
Percentage by Mass Passing
50 mm
100
37.5 mm
95 - 100
20 mm
60 - 80
10 mm
40 - 60
5 mm
25 - 40
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Section 2 - Materials
2.36 mm
15 - 30
600 µm
8 - 22
75 µm
0-8
2. The particle size shall be determined by the washing and sieving method of
BS EN 933-3.
3. Aggregate quality and cleanliness shall comply with the relevant requirements
of Clause 2.4. The flakiness index shall be less than 35 when determined in
accordance with BS EN 933-3.
4. The moisture content of the wet-mix macadam shall be the optimum ± 0.5%,
as determined in accordance with BS 5835-1.
2.138 WINDOWS
1. Windows, window surrounds and fixings shall comply with the relevant
provisions of the appropriate Standard, as set out in the following table:
Material/Type
Standard
Wood
BS 644
Steel
BS 6510
Aluminium
BS 4873
Plastics (PVC-U)
BS 7412
2.139 WINDOW SILLS
1. Precast concrete, cast stone, clayware, slate and natural stone window sills
shall comply with the relevant provisions of BS 5642-1.
2. Steel window sills shall comply with the relevant provisions of BS 6510.
2.140 WOOD FLOORING
(i) The required type and finished
thickness of flooring should be
described in the Contract.
1. Tongued and grooved softwood board and strip floorings shall be graded and
sized in accordance with the relevant provisions of BS 1297.
2.141 WOOD TRIM
(i) The relevant design reference in
BS 1186-3 should be described in
the Contract.
1. Wood trim in the form of architraves, skirtings, picture rails, cover fillets,
quadrant, half-round and scotia moulds shall comply with the relevant provisions
of BS 1186-3.
2.142 WROUGHT ALUMINIUM AND ALUMINIUM ALLOY
1. Wrought aluminium and aluminium alloys shall comply with the relevant
provisions of the appropriate Standard, as set out below:
Type
Standard
Sections for structural purposes
BS 1161
Plate, sheet and strip
BS EN 485-1
Drawn rod, bar and tube
BS 754-1
Extruded rod, bar, tube and profiles
BS 755-1
Castings
BS 1559-1
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Services Ltd
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2.143 (N)
SURFACE HARDENERS TO CONCRETE FLOOR
2.143.1
Surface hardeners shall be based on "activated" sodium silicate
or magnesium silico-flouride. Alternatively materials for the
production of hard-wearing floor surfaces shall be purposedesigned, proprietary “dry-shake” materials or impregnations of
acrylic or polyurethane, provided they meet the other requirement
of this specification, and applied fully in accordance with the
manufacturers’ instructions.
Yorkshire Water
additional, new
clauses
Services Ltd
or substitute
2.144 (N)
DISSIMILAR METALS
2.144.1
Where dissimilar metals are used in contact with each other the
risk of bimetallic corrosion shall be assessed with reference to
BSPD6484. If the relevant tables in BSPD6484 indicate a risk
level of <2 for a given environment no isolation of materials is
required. Where the relevant tables in BSPD6484 indicate a risk
= or >2 isolation of the materials shall be required.
2.144.2
Isolation shall be provided by materials that electrically insulate
the different metals. In the case of structural steel the provision
of corrosion protection coatings in accordance with Clause 6.20
of this specification shall be adequate insulation for steel that is
not immersed in water.
2.144.3
For dissimilar metal contacts in building with controlled
environments no insulation shall be required.
2.145 (N)
THERMAL INSULATION
2.145.1
Where the Contract requires the installation of thermal insulation
it shall be supplied and installed in accordance with BS 5422.
2.145.2
All insulation on the Site shall have an identical finished
appearance.
2.145.3
All vessels and associated pipework located outside shall be
protected from the elements by suitable rodent proof means.
Insulation and trace heating applied to valves, flanges, fittings and
pump casings shall permit easy removal and replacement for
inspection and maintenance.
2.146 (N)
PIPEWORK
2.146.1
Materials for pipes and fittings shall be selected from the following
table according to duty and diameter range. Requirements
associated with other uses / services and fluids (e.g. chemicals)
shall
be
detailed
in
the
Particular
Specification.
These shall also comply with Clause 2.129.10 (A).
2.146.2
Pipes with puddle flanges shall be supplied in all cases where the
pipework passes through sub-structures or structures designed to
retain water. Where puddle flanges are required to carry thrust
they shall be cast integrally with the pipe or welded to the pipe
and designed to withstand the maximum force taking into account
of maximum test pressures and all other loadings on the pipe.
Clamp type puddle flanges are not permissible where required to
carry thrust.
2.146.3
Adequate supporting arrangements for all pipes and valves shall
be provided. Where pipework is installed either vertically or at
significant slopes the vertical supports shall be designed to carry
the total weight of the pipe and contents.
2.146.4
The Contractor shall supply brackets, saddles, hangers, clamps,
supports, anchors, clips, fastenings, straps and fixings to fix the
pipe runs to the civil structure. All supports shall be protected
against corrosion or fabricated from a corrosion resistant material.
All fixings to the pipework shall be fitted with neoprene strips to
ensure that paintwork is not damaged. Support material of
construction shall either be metal or concrete.
Yorkshire Water
additional, new
clauses
Yorkshire Water
additional, new
clauses
Services Ltd
or substitute
Services Ltd
or substitute
Applicable where design is by the
Contractor. See also Pipework
Identification below and YWS Eng.
Spec Section 06 ICA and YWS
Eng. Spec Section 03.08 Fire
Protection
and
Detection
Installations)
CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
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Section 2 - Materials
2.146.5
Drain points shall be provided in order to drain and scour all
distribution and rising main pipework. Where appropriate isolating
valves shall be fitted to each tapping. The location of the tappings
shall be the responsibility of the Contractor.
2.146.6
Couplings or flange adaptors shall be installed where removing of
plant for maintenance is required.
CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
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Section 2 - Materials
TABLE 2.148
SERVICE
SIZE RANGE
PIPE MATERIAL (In accordance with requirements of this specification)
Buried
Pipelines
Conveying Water for
Public Supply
Up to & including
DN300
Ductile Iron
PVC-A
High Performance Polyethylene
Medium Density Polyethylene
PVC-O
Steel(including stainless)
DN300 to DN600
Ductile Iron
High Performance Polyethylene
PVC-O
PVC-A
Steel(including stainless)
Greater than
DN600
Ductile Iron
Steel(including stainless)
High Performance Polyethylene
PVC-O
Above
Ground
Pipework and within
Structures
Up to & including
DN300
Ductile Iron
PVC-A
Steel(including stainless)
ABS
Sewage
mains)
(pumping
Greater than
DN300
Ductile Iron
Up to & including
DN300
Ductile Iron
Steel (including stainless)
High Performance Polyethylene
Medium Density Polyethylene
PVC-O
PVC-A
Greater than
DN300
Ductile Iron
High Performance Polyethylene
PVC-O
PVC-A
Steel(including stainless)
Compressed Air
All diameters
Galvanised mild steel
Copper
Stainless Steel
Chemical Dosing
All diameters
To suit the particular fluid being carried and in accordance with the
manufacturers’ instructions
Note: GRP pipe and fittings may be determined suitable for certain applications above, see 2.52.
Yorkshire Water Services Ltd additional,
new or substitute clauses
CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
2.147 (N)
PROTECTIVE COATING TO CONCRETE
2.147.1
Protective coatings to concrete for aggressive ground
conditions shall be bitumen/rubber latex emulsions or
purpose-designed polymeric systems (e.g. epoxy resins)
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Yorkshire Water Engineering Specification
Section 2 - Materials
applied fully in accordance with the manufacturer’s
instructions.
Yorkshire Water Services Ltd additional,
new or substitute clauses
Yorkshire Water Services Ltd additional,
new or substitute clauses
CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
2.148 (N)
GROUND GRANULATED BLAST FURNACE SLAG
2.148.1
Ground granulated blastfurnace slag (ggbs) for use with
Portland cement shall comply with BS 6699 or BS EN 151671.
2.148.2
Ground granulated blastfurnace slag (ggbs) for use with
cementitious materials shall have an alumina (Al2 O3)
content not exceeding 14% by mass.
2.148.3
Each consignment of GGBS to be used in the works shall be
accompanied by a certificate of compliance with BS 6699 or
BS EN 15167-1.
2.149 (N)
PIPEWORK IDENTIFICATION
2.149.1
All pipework painted in the basic colour to have banding
colours repeated at all junctions, at both sides of valves, at
appliances, bulkheads, wall penetrations and any other
points where identification is deemed necessary. All other
pipework shall banded with the basic colours and banding
colours at all points mentioned above.
2.149.2
Pipe identification banding shall be in accordance with
BS 1710. But, where there is a contradiction between the
Employer’s Banding Code and the optional coding in
BS 1710, the Employer’s coding scheme shall be used.
2.149.3
All pipework shall have direction of flow indication. This shall
be in accordance with BS 1710.
2.149.4
Valves shall be generally painted in the basic colour of the
pipework in which they are situated. If further identification is
considered necessary, the top flange shall be painted in the
relevant banding colour.
2.149.5
Information regarding the specific nature of the pipework
contents shall be affixed to the pipework and repeated at
regular intervals in accordance with BS 1710.
2.149.6
Where pipes containing chemicals are installed, colour
banding identification reference panels shall be mounted,
detailing the contents of each pipe within the area.
2.149.7
Visible pipes containing or transporting dangerous
substances or preparations must be labelled with a
pictogram or symbol as required by the Health and Safety
(Safety Signs and Signals) Regulations 1996. These shall be
positioned on the pipe at the most dangerous points, such as
valves and joints, and at regular intervals.
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Yorkshire Water Engineering Specification
Section 2 - Materials
Employer’s Banding Code
Pipe content
Category
Specific Contents
Basic
identification
colour
BS
4800
Code
Colour code
identification
BS 4800
Code
WATER
Raw / Untreated
Green
12D45
Nil
-
Sea / Brine solution
Green
12D45
Emerald Green
14E53
Treated / Drinking
Green
12D45
Blue
18E53
Cooling
Green
12D45
White
00E55
Boiler Feed
Green
12D45
Crimson
04D45
White
00E55
Crimson
04D45
Crimson
04D45
Emerald Green
14E53
Crimson
04D45
White
00E55
Emerald Green
14E53
White
00E55
Blue
18E53
Crimson
04D45
Blue
18E53
Crimson
04D45
Blue
18E53
Crimson
04D45
White
00E55
Blue
18E53
White
00E55
White
00E55
Crimson
04D45
White
00E55
Condensate
Chilled
Heating < 100oC
Green
Green
Green
12D45
12D45
12D45
(Incl. Central Heating)
Heating > 100oC
Green
12D45
(Incl. Central Heating)
Cold Down Service
Hot Water Supply
EFFLUENTS
AIR
Green
Green
12D45
12D45
Hydraulic Power
Green
12D45
Salmon Pink
04C33
Fire Extinguishing Service
Green
12D45
Safety Red
04E53
Primary -
Green
12D45
Black
00E53
Yellow
08E51
Black
00E53
Salmon Pink
04C33
Black
00E53
Crimson
04D45
Black
00E53
Red
04E53
Black
00E53
White
00E55
Humus – Washwater
Supernatant
Green
Activated - Thickener
Supernatant
Green
Liquors – Regeneration
Green
12D45
12D45
12D45
Final – Centrifuge or
Press
Green
Compressed
Light Blue
20E51
Nil
-
Vacuum
Light Blue
20E51
White
00E55
CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
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12D45
Version 20 – April 2020
Yorkshire Water Engineering Specification
Section 2 - Materials
Pipe content
Category
Specific Contents
Basic
identification
colour
BS
4800
Code
Colour code
identification
BS 4800
Code
STEAM
-
Silver grey
10A03
Nil
-
ELECTRICAL
Conduits and Trunking
Orange
06E51
Nil
-
GASES
Natural incl. Methane
Yellow Ochre
08C35
Nil
-
Town Gas (manufactured)
Yellow Ochre
08C35
Emerald Green
14E53
Butane
Yellow Ochre
08C35
Grey Green
14C35
Propane
Yellow Ochre
08C35
Red
04C53
Chlorine Cl2
Yellow Ochre
08C35
Yellow
08E51
Ammonia
Yellow Ochre
08C35
Dark Mauve
02C37
Sulphur Dioxide SO2
Yellow Ochre
08C35
Blue
18E53
Oxygen O2
Yellow Ochre
08C35
White
00E55
Ozone O3
Yellow Ochre
08C35
Crimson
04D45
Gas / Furnace
Brown
06C39
Nil
-
Diesel
Brown
06C39
White
00E55
Lubricating
Brown
06C39
Emerald Green
14E53
Hydraulic
Brown
06C39
Salmon Pink
04C33
Transformer
Brown
06C39
Crimson
04D45
Sulphuric Acid H2SO4
Violet
22C37
Nil
-
Ferric / Ferrous Sulphate
Violet
22C37
Blue
18E53
Hydrofluorosilicic Acid
H2SiF6
Violet
22C37
Crimson
04D45
Sodium Carbonate
Na2CO3
Violet
22C37
White
00E55
Sodium Hypochlorite
NaOCl
Violet
22C37
Yellow
08E51
Sodium Aluminate
Violet
22C37
Emerald Green
14E53
Caustic soda NaOH
Violet
22C37
Red
04E53
Aluminium Sulphate
Violet
22C37
Salmon Pink
04C33
Lime CA(OH)2
Violet
22C37
Black
00E53
Copperas FeSO4
Violet
22C37
Yellow
08E51
White
00E55
Emerald Green
14E53
White
00E55
Red
04E55
White
00E55
Blue
18E53
white
00E55
Black
00E53
White
00E55
OILS
ACIDS & ALKALIS
(Alum) Al2(SO4)3
Aluminium Chlorohydrate
[Al2(OH)2Cl]X
Violet
Poly-Electrolyte
Violet
Ferric Chloride FeCl3
Waste Pickling Liquor or
Chemicals
CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
Violet
Violet
Page 94 of 192
22C37
22C37
22C37
22C37
Version 20 – April 2020
Yorkshire Water Engineering Specification
Section 2 - Materials
Pipe content
Category
Specific Contents
Basic
identification
colour
BS
4800
Code
Colour code
identification
BS 4800
Code
SLUDGE
Primary – Clarification
Black
00E53
Yellow
08E51
Humus - Washwater
Black
00E53
Salmon Pink
04C33
Activated-Thickened
Black
00E53
Crimson
04D45
Digested
Black
00E53
Emerald Green
14E53
Heat treated
Black
00E53
Red
04E53
Grit / Screenings
Black
00E53
Blue
18E53
Drainage
Black
00E53
Nil
-
Granulated Activated
Carbon
Black
00E53
White
00E55
Yellow
08E51
Magnetite
Black
White
00E55
OTHER LIQUIDS
Yorkshire Water Services Ltd additional,
new or substitute clauses
00E53
2.150 (N)
PRE-CAST POST-TENSIONED CONCRETE TANKS
2.150.1
Manufacture of panels shall be by the accepted tank sub
contractor and shall not be sub contracted out to any others.
2.150.2
An anchorage system that can be readily inspected and
maintained shall be used with the tendons. This shall
incorporate a method of preventing tendons from ejecting
from ducts on failure in order to reduce the risk of injury.
However, the system adopted shall ensure that a failed
tendon can clearly be observed without the need to dismantle
any guards or covers.
2.150.3
Each tendon shall be protected along all of its length against
contact with water.
2.150.4
Seals preventing water ingress through joints shall remain
under compression under all operational conditions.
2.150.5
A degree of tendon redundancy shall be provided to prevent
catastrophic failure of the tank. The minimum redundancy
shall allow for up to two tendon failures.
2.150.6
Seals shall have a minimum design life equal to that of the
concrete structure.
2.150.7
Tendons shall be resistant to stress corrosion cracking.
2.150.8
The method of storage of tendons and associated
components shall ensure that there is no contact with water
or any other contaminants.
2.150.9
The following are required prior to acceptance of the sub
contractor:
(a) An additional level of technical assurance during
manufacture shall be provided. This shall be in the form
of certification to demonstrate that procedures, materials
and workmanship are to an appropriate standard. Details
of how this is to be done shall be provided.
(b) An additional level of independent supervision shall be
provided by the sub contractor, overseeing off-loading
and installation. This person shall be responsible for
certifying that the work has been carried out in accordance
with the sub contractor’s procedures. Details of their
experience and training shall be provided.
CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
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Yorkshire Water Engineering Specification
Section 2 - Materials
2.150.10
The following
manufacture:
are
required
for
acceptance
prior
to
(a) Calculations to demonstrate that all loadings have been
taken into account.
(b) Calculations to demonstrate that seals remain in
compression under all operational conditions and that
there is adequate tendon redundancy in the design.
(c) Details to demonstrate the design life of the seals.
(d) Details to demonstrate tendon resistance to stress
corrosion cracking.
(e) The principal and sub contractors risk assessments.
2.150.11
The following are required for acceptance prior to delivery:
(a) Details of the installation team's experience and training.
(b) Details of how over stressing of the tendons will be
prevented during erection.
(c) Method for sealing minor leakage at cracks.
(d) Method for sealing leakage at joints. The method shall
include the flowing requirements:
(e) If a tank fails its water test due to leakage at a joint then
the first course of action shall be to re-erect the tank,
During this process the following shall be done:
(f)
The panels shall be checked for tolerance and fit.
(g) Seals shall be checked for defects / incorrect fitting.
(h) Defects in the above shall be corrected.
(i)
Yorkshire Water Services Ltd additional,
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Any tendons which are at risk of being in contact with
water shall be withdrawn and inspected. If a tendon has
been in contact with water it shall be replaced.
2.151 (N)
STORAGE OF MATERIALS
2.151.1
All materials to be used or incorporated in the Works shall be
stored in accordance with the recommendations of the
appropriate manufacturer or supplier.
2.151.2
Any potable water pipes or fittings that are subjected to any
contamination particularly with hydrocarbon solvents, fuels
and oils, shall be removed from site and disposed of. On no
account shall they be included in the works.
2.151.3
All pipes and fittings, especially polyethylene pipes, and
layflat potable water hoses, shall be stored away from
exhaust outlets and all other high temperature sources.
2.151.4
The Contractor shall ensure that any small moveable
materials or fittings (bends, flanged risers, concrete sections,
surface boxes etc.) are not left on site unattended and are
adequately secured or removed from site at night to prevent
them being stolen, or used in acts of vandalism. Larger
fittings and pipes which cannot be easily removed from the
site should be banded together and pegged/secured to
prevent them being pushed or rolled into roads, footpaths or
gardens.
2.151.5
Polyethylene pipes, layflat potable water hoses and fittings
shall be transported on vehicles provided with a flat bed, free
from nails and other projections which may result in damage
to the materials. Only non-metallic ropes or wide band
webbing shall be used to secure loads.
2.151.6
In circumstances where materials required to carry out a
Service Order are not available from the Employer’s Materials
CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
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Section 2 - Materials
Framework Supplier, the Contractor shall confer with the
Employer’s procurement service and take whatever agreed
action is deemed necessary to procure such items.
2.151.7
The Contractor shall utilise a computerised stores
management system to
control and maintain stock levels.
The Employer shall from time to time require access to the
store management system for the purpose of material audit.
2.151.8
Any potable water equipment, pipework, fittings or materials
which are to be used in restricted operation activities must be
held in hygienic stores or workshops. Stores may be
maintained on Contractor or Company operational sites. The
store should be located as far away as feasibility possible
from any point of contamination in order to minimise the risk
of contamination from liquid or airborne particles.
2.151.9
In the case of minor contamination, the Contractor will ensure
that all fittings are subject to sufficient cleaning before use in
line with the Company's procedures. Any potable water
equipment, pipework, fittings or materials that are subjected
to sewage contamination on a waste water site, shall be either
discarded or cleaned and disinfected by the Contractor in
accordance with the requirements of the Company before
use.
2.152 (N)
THE EMPLOYER’S MATERIALS FRAMEWORK SUPPLIER
PERFORMANCE
2.152.1
In order to allow the Employer to monitor the performance and
level of service received from the Employer’s Materials
Suppliers, the Contractor shall provide, on a regular basis,
performance information for each materials supplier detailing
the following:
(i) Delivery performance, meeting of lead times
(ii) Issues regarding the quality of the product
2.152.2
CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
To enable the Employer’s Materials Framework Suppliers to
optimise efficiency of production, the Contractor will provide
estimated usage.
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Section 3 - Excavation, Backfilling and Restoration
SECTION 3
EXCAVATION, BACKFILLING AND RESTORATION
The Notes for Guidance are not part of
the Specification.
3.1 EXCAVATION
(i) The following publications give
recommendations as to standards of
good practice for excavation:
BS 6031;
BS 6164;
Report R97, ‘Trenching Practice',
published by CIRIA; and
Technical Note TN95 ‘Proprietary
Trench Support systems’, published by
CIRIA.
(ii) A definition of rock shall be included
in the Contract.
(iii)
The
relevant
Highway
Reinstatement
Specification
Roles
should be defined in the Contract.
(iv) Any special requirements for Site
clearance or for the disposal of
excavated
materials
should
be
described in the Contract.
(v) The Contract should describe the
extent of any excavations where
battered sides will be permitted. A detail
of the allowable cross-section should be
given.
1. Operations shall be carried out in such a manner as to prevent damage
to, or deterioration of, the formation of excavations.
2. Excavation in roads and streets shall be carried out in accordance with the
relevant Highway Reinstatement Specification.
3. Excavations in locations where services may be encountered shall be
carried out in accordance with ‘HSG 47 Avoiding Danger from Underground
Services’.
4. Trenches shall be excavated so that the effective width is maintained
within any limit imposed by the design of the pipeline. The sides of
excavations shall be adequately supported at all times and, except where
described in or permitted under the Contract, shall not be battered.
5. Unsuitable ground or damaged surfaces below formation shall be
excavated and then filled to formation level, with the material shown on the
drawings or otherwise specified in the Contract. Any void that results from
over-excavation shall be filled with the material stated in the Contract.
6. Excavated granular material which can be reused shall be kept separate
from excavated cohesive materials.
7. Trenches in rock for flexible pipes shall be excavated to provide a
minimum clearance of 100 mm around the outside of pipe barrels and joints
for pipes up to 100 mm nominal bore, and 150 mm for pipes of larger nominal
bore. For rigid pipes the minimum clearance shall be 200 mm.
8. Trenches for pipes carrying water under pressure shall, except where
otherwise described in the Contract, be excavated to a sufficient depth to
ensure a minimum cover to the top of the pipes as specified by clause 5.1.11
(A).
(vi) Excavation in carriageways should,
wherever possible, be located such that
the edge of the opening is at least 1 m
from the edge of the carriageway.
(vii) Care should be taken when siting
spoil heaps to avoid damaging trees by
impinging on their root spread.
(viii) Excavated material for disposal off
Site would normally be classified as
controlled waste and the Client, under
the Environmental Protection Act 1990,
has a duty of care to ensure that the
Works are carried out in compliance with
the legislation relating to the treatment,
keeping or disposal of such material.
(ix) Reference should be made to The
Financing Act 1996 (Landfill Tax).
(x) Stored excavated granular material
may require draining to achieve
acceptable water content.
CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
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Yorkshire Water Services Ltd additional,
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Yorkshire Water Services Ltd additional,
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Section 3 - Excavation, Backfilling and Restoration
3.1.2 (S)
Excavations in roads, streets, private land and private streets
shall be carried out in accordance with the relevant provisions
of the HAUC ‘Specification for the Reinstatement of Openings
in Highways’.
3.1.4 (S)
Trenches shall be excavated so that the effective width is
maintained within any limit imposed by the design of the
pipeline. The sides of excavations shall be adequately
supported at all times. The Contractor shall use his own
discretion in determining if the sides of the excavation should
be battered.
3.1.9 (A)
Works shall be undertaken in such a manner as to avoid the
need for excavations. This shall require the Contractor to
develop, deploy and maximise the use of no-dig technologies
and solutions.
3.1.10 (A)
Kerbstones, paving slabs, setts, block pavers, frames and
gratings etc. removed during excavations shall be carefully
set aside and safely stored for re-use.
3.1.11 (A)
Where excavation is required to be carried out the Contractor
shall, unless operational circumstances prevail, excavate to
minimum sizes and will either backfill or utilise secure road
plates and/or footpath boards as soon as possible so that
cones, barriers and signs can be removed from sites thus
minimising hindrance to residents and road users. Where
Service Products are used the Contractor shall identify and
list in a schedule the minimum size of excavation for each of
the Service Products described in the Contract, providing a
reason for his assumptions and taking into account the
Service Products Standards.
3.1.12 (A)
Where excavation is required to be carried out the Contractor
shall, unless operational circumstances prevail, excavate to
minimum sizes. The Contractor shall identify and list in a
schedule the minimum size of excavation for each of the
Service Products described in the Contract, providing a
reason for his assumptions and taking into account the Asset
Standards in Schedule 2, Annex 1.
3.1.13 (A)
Excavations shall be of sufficient depth to fully expose
existing pipework, particularly when undertaking repair
related Service Products.
3.1.14 (A)
The Contractor shall, wherever practical and economical,
adopt vacuum excavation technology to everyday excavation
work.
3.2 RELAYING TURF
1. Good practice dictates that turves shall be green when cut, they shall be
kept moist and shall be re-laid in suitable weather conditions.
2. The level of topsoil beneath turves shall be such that the final grass
surface after compaction shall be flush with the adjoining grass surface.
CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
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Section 3 - Excavation, Backfilling and Restoration
3.3 TOPSOIL FOR RE-USE
(i) It is advisable to make an assessment
of soil stacking requirements in cases
where topsoil quality is important, and to
provide accordingly in the Contract
1. “Topsoil” shall mean the top layer of soil that can support vegetation. It
shall include all turf not required for relaying or not acceptable for turfing
under Clause 3.2.
2. Topsoil shall be removed from the areas described in the Contract and,
where required for re-use, shall be stockpiled separately and kept free from
weeds.
3. Handling of topsoil shall be in accordance with BS 3882.
4. Topsoil stripping, stockpiling and replacement shall be conducted in such
a manner as to minimise damage to the soil structure.
Yorkshire
Water
Services
Ltd
additional, new or substitute clauses
3.3.5 (A)
Where excavation is carried out in private gardens, verges or
agricultural land, the topsoil shall be removed to a depth of
not less then 200mm and set aside separately and distinctly
from any sub-soil material. Alternatively, imported topsoil
may be used to a depth of 100mm or to match the existing
depth of topsoil whichever is less. The topsoil shall be
replaced in its original position upon backfilling, and all stone
over 25mm diameter shall be removed.
3.3.6 (A)
The Contractor may use the Employer’s sludge phytoconditioning (hereinafter termed ‘SPC’ as topsoil. The
material complies with the British Standard for topsoil (BS
3382) and will be made available free of charge from specified
locations in the Area.
3.4 DEALING WITH WATER
(i) Any requirements for prevention of
the deposition of silt and/or protection
from erosion should be set out in the
Contract.
1. Water shall not be allowed to lie anywhere within excavations, unless so
required under the Contract. Any drainage sumps required shall, where
practicable, be sited outside the area excavated for the Works and shall be
re-filled with approved material to the level of the underside of the adjacent
permanent Works.
2. All necessary precautions shall be taken to prevent any adjacent ground
from being adversely affected by loss of fines through any dewatering
process.
3. Groundwater shall not be allowed to enter mains to be used for the
conveyance of potable water.
4. The Contractor shall provide method statements and details of pollution
prevention measures relating to the control and disposal of groundwater from
de-watering operations. Discharging shall be subject to the Contractor
obtaining prior written approval from the appropriate consenting body.
Yorkshire Water Services Ltd additional,
new or substitute clauses
3.4.3 (S)
Groundwater or water discharges shall not be allowed to enter
mains and services to be used for the conveyance of potable
water during construction. Open pipe ends must always be
sealed using a water-tight plug.
Yorkshire Water Services Ltd additional,
new or substitute clauses
3.4.5 (A)
Manhole and inspection covers shall not be lifted to facilitate
the drainage of water, without approvalof local sewerage
department, nor must any road gullies, private gullies or
grates be used without approval.
3.4.6 (A)
Where contamination of mains and/or other services is
believed to have occurred the Contractor shall immediately
contact the Employer for instruction. Water arising from or
drawing into the Works shall be drained or pumped to an
approved disposal point. The Contractor shall avoid damage
to the surrounding surface during draining or pumping.
3.4.7 (A)
The Contractor shall use appropriate filters attached to pump
outlets, or other approved methods, in order to minimise silt
and contaminated water discharges.
CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
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Yorkshire Water Engineering Specification
3.4.8 (A)
Section 3 - Excavation, Backfilling and Restoration
If road gullies are to be used for the disposal of water, the
Contractor shall ensure that they are clear both before and
after their use in connection with the Works.
3.5 TEMPORARY DRAINS
1. Where temporary drains are required, they shall be laid in a narrow trench
or grip formed below the bottom of the excavation in an approved position.
The pipes shall be open-jointed and shall be surrounded with free-draining
granular material.
2. When no longer required, temporary drains shall be removed or sealed.
3. When sealing temporary drains, grouting pipes shall be inserted in the line
of the temporary drains at intervals not exceeding 25 m. The drains shall be
solidly filled with grout (Class G3 or G4) and the grouting pipes cut off on
completion of the filling. Care shall be taken to avoid impregnation of the
granular bedding material around the main pipeline.
3.6 BACKFILLING
(i) Any special requirements for
backfilling around mains and services
should be described in the Contract.
(ii) Any particular requirements for the
materials to be used for backfilling
should be described in the Contract.
1. Backfilling shall, wherever practicable, be undertaken immediately the
specified operations preceding it have been completed. Backfilling shall not,
however, be commenced until the Works to be covered have achieved a
strength sufficient to withstand all loading imposed thereon.
2. Backfilling shall be undertaken in such a manner as to avoid uneven
loading or damage.
(iii) No materials should be stored on
roofs of tanks without the written
approval of the Client.
3. Filling material to excavations not situated in the highway shall be in
accordance with Clause 2.50, placed and compacted to form a stable
backfill.
(iv) When considering the requirements
for
backfilling
to
water-retaining
structures, reference should be made to
Section 7.14 of this Specification.
4. Excavations in roads and streets shall be filled above the level of any pipe
surround required, in accordance with the relevant Highway Reinstatement
Specification.
Yorkshire Water Services Ltd additional,
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3.6.6 (A)
The use of recycled or reuse of existing materials shall be the
preferred method of backfilling excavations. The Contractor
shall comply with the manufacturer’s recommendations and
the Reinstatement Specification when using recycled
materials. In Highways, only recycled materials that are
approved by the Street Authority shall be used and the
Contractor shall comply with any provisions requested by the
Street Authority when using recycled materials.
3.6.7 (A)
Where recycled materials cannot be used, excavations in
carriageways or within 1metre of the edge of the carriageway
shall be backfilled with foamed concrete or granular sub-base
type 1 and compacted in accordance with the Reinstatement
Specification.
5. Where the excavations have been supported and the supports are to be
removed these, where practicable, shall be withdrawn progressively as
backfilling proceeds, in such a manner as to minimise the danger of collapse,
and all voids formed behind the supports shall be carefully filled and
compacted.
3.7 REINSTATEMENT OF MAINTAINABLE HIGHWAYS
(i) Any particular requirements for the
reinstatement method, materials and
depths of layers should be described in
the Contract.
1. Reinstatement of roads and streets (including carriageways footways,
footpaths, cycle tracks and verges) which are maintainable highways shall
be undertaken in accordance with the relevant provisions of the relevant
Highway Reinstatement Specification.
(ii) Reinstatement of surface boxes is
covered in Clause 5.21.
2. Road categories and reinstatement requirements shall be obtained from
the relevant Highway Authority and comply with the New Roads and Street
Works Act.
(iii) Reference should be made to the
New Roads and Street Works Act.
3. Kerbs, channels, edgings and quadrants disturbed by the Works shall be
re-laid with existing units, providing they are not damaged. Where existing
units are not suitable for re-use, replacement units of similar texture, colour
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and type, consistent with those adjacent and complying with the relevant
provisions of Clause 2.35 or 2.98, as appropriate, shall be provided.
4. The re-laying of kerbs, channels, edgings and quadrants shall be in
accordance with Clause 8.10. In-situ kerbs and channels shall be reinstated
to conform with adjoining kerbs and channels.
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3.7.5 (A)
The specification for reinstatement in highways shall be the
HAUC “Specification for the Reinstatement of Openings in
Highway" incorporating the following amendments:Generally for "Undertaker" read "Contractor" or "Contractor’s
Representative”
Extract from:
S8.1
Reinstatement Methods.
sentence to the following:
Amend the first
The Contractor shall carry out reinstatement in accordance
with one of the following methods and should endeavour to
achieve the greatest degree of immediate permanent
reinstatement.
A8
Compaction Requirements. Amend the title to
"Minimum Compaction Requirements"
3.7.6 (A)
Arrangements shall be made by the Contractor to obtain
materials from suppliers during recognised construction
industry holiday periods to ensure interim works are
minimised. These costs shall be borne by the Contractor.
3.7.7 (A)
The Reinstatement Specification has, in parts, for the purpose
of this contract been amended and the number of
reinstatement options has been reduced.
(i)
(i)
Reference to the ‘Undertaker’ will generally, depending on
the context, be read as ‘the Contractor’. Reference to the
‘Authority’ will generally be read as the Employer.
Reference to the ‘Authority’ will be read as the ‘Street
Authority’. Where the responsibility for any other aspect of
this work is unclear, the Contractor shall request clarification
from the Employer’s Street Works Improvement Manager.
Flexible and Composite roads shall be reinstated in
accordance with either Method A or B as specified in S6.1
of the Reinstatement Specification, unless otherwise
agreed with the Employer. For avoidance of any doubt the
Contractor shall use backfill material in accordance with
S5.1
(iii) Where the Contractor may propose to use limestone
aggregate exposed at the road surface in either a
permanent or temporary reinstatement wearing or base
course material he shall prior to its use provide the Employer
with documentary proof that the proposed aggregate can
adequately meet the skid resistance/polished stone
requirements for the whole of its life.
(iv) The Contractor shall ensure that any interim reinstatement
conforms to the prescribed standards until the permanent
reinstatement is completed, and that the permanent
reinstatement conforms to the prescribed standard
throughout the guarantee period. The guarantee period
shall begin after completion of the permanent reinstatement
and the serving of a Statutory Notice with works status
‘Works Closed’ to the Street Authority.
(v) Where it is necessary to re-excavate a reinstatement, the
further reinstatement shall be deemed to be new and the
guarantee period shall begin again upon its completion.
(vi) If, at the end of the guarantee period, the uniformity of the
adjacent surface is superior to the reinstatement, due to the
profile of the reinstatement, the Contractor shall carry out
remedial action to achieve a reinstatement surface
consistent with the adjacent surfaces.
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3.7.8 (A)
3.7.9 (A)
Section 3 - Excavation, Backfilling and Restoration
(vii) Where excavations are carried out in base roads or paths
(i.e. roads or footpaths which have only been constructed to
base course level by the developer and are awaiting
application of the final wearing course) they shall be
reinstated using the appropriate method less wearing
course.
During recognised construction industry holiday periods, it is
likely that suppliers of reinstatement materials will close down
their plants for a number of days. The Contractor must either
make arrangements such that he has access to the
appropriate materials over this period, or discuss with the
Employer and/or the local Street Authority, or any affected
customers alternative proposals which may include the use
(by agreement with the Employer) of temporary surface
reinstatements during the suppliers closedown period.
Preference shall be given to a first visit reinstatement where
the entire structure is reinstated to a permanent standard at
the first visit.
The Contractor executing work in the
Maintainable Highway shall carry out the excavation and
reinstatement and cease to occupy the site to a method,
which incorporates the highest degree of same day
permanent reinstatement. Any requirement to extend works
beyond the same day shall be determined by mutual
agreement (Contractor and the Employer) from consideration
of the work content and complexity and whenever possible
prior to commencement of the works on site.
3.8 REINSTATEMENT OF NON-MAINTAINABLE HIGHWAYS
(i) Where the relevant Highways
Reinstatement
Specification
is
inappropriate, the reinstatement should
be described in the Contract.
1. Non-maintainable highways shall, except where otherwise stated in the
Contract, be reinstated in accordance with the relevant provisions of
Clause 3.7.
(ii) Any discussions with the landowner
should be carried out through a land
agent.
3.9 REINSTATEMENT OF UNPAVED LAND
(i) Any special grass seed mixtures
required, differing from those specified
in Clause 2.56, should be described in
the Contract.
(ii) Any requirements to apply fertiliser
should be described in the Contract.
(iii) Any special provisions for the
reinstatement of land should be set out
in the Contract, including the use of deep
ploughing where overcompaction of the
unpaved land has occurred.
1. Proposals for reinstatement shall be discussed with the landowner prior to
any work commencing (see Section 1.7). Subsoiling of the working strip is
required, unless otherwise stated in the Contract.
2. The surface of all land affected shall be broken up, to a depth of at least
300 mm, and stones and extraneous material greater than 50 mm in size
cleared before topsoil is replaced. The land shall be cultivated and restored
as closely as possible to its original condition.
3. Surfaces to be sown with grass seed shall be reduced to a fine tilth and
cleared of stones and extraneous material greater than 50 mm in size. The
seed shall be sown at the proper season, evenly distributed and applied at a
rate of not less than the quantities given in the following table:
Level Surfaces (g/m2)
(iv) Any requirements for grass cutting
and weed killing should be described in
the Contract.
Nature of Area to be
Seeded
Sloping Surfaces to
Cuttings and
Embankments (g/m2)
(v) Newly-turfed areas on slopes of
cuttings and embankments may require
to be secured.
Lawns
60
-
Surrounds to tanks and
process plants
25
35
Agricultural land and
roadside verges
6
10
4. Surfaces to be turfed shall be prepared as for seeding. Turves shall be
placed, butted, interlocked and tamped, and the joints filled with fine sandy
soil. On sloping ground, where they may be likely to slip, turves shall be laid
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diagonally. Any subsidence taking place shall be made good by taking up
the turf, filling with good, finely-sieved topsoil and replacing the turf in the
manner specified above. Any turf that dies shall be replaced with new turf.
5. Hydraulic mulch seeding shall be carried out using a proprietary process
and shall contain types of seed, mulch material, fertiliser and other necessary
additives to produce a covering of sward on subsoil.
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3.9.6 (A)
The Contractor shall be responsible for maintaining all seeded
and turfed areas until they are satisfactorily established. The
Contractor shall also provide the first two cuts of any restored
areas affected by the Works, on the Employer’s operational
land. Turves to be laid diagonally on slopes steeper than 10°.
In cases where the verge is maintained e.g. cut frequently by
residents, village greens or the like replacement turf is to be
laid and maintained until established.
3.9.7 (A)
The Contractor shall undertake the reinstatement of Verges
and Unmade Ground (includes land adjacent to road
structures, cultivated areas, grassed areas and verges,
ditches and drainage courses) in accordance with S9 of the
Specification for the Reinstatement of Openings in the
Highway (SRoH).
3.9.8 (A)
Grassed areas shall be reinstated wherever possible using
the original turf with damage being kept to a minimum or
replacement turf or an equivalent seed, depending on
weather and growing season. In all cases, a reasonable
height and density of grass shall be established within the
following 12 months.
3.9.9 (A)
The grass seed mixture shall generally be in accordance with
clause 2.56, mixture 1, but where requested by a landowner
or customer, other mixes may be required to comply with his
requirements.
3.10 TREES
(i) NJUG (National Joint Utilities Group)
Publication Volume 4 ‘Guidelines for the
Planning, Installation and Maintenance
of Utility Services in Proximity to Trees’,
gives guidance on working near trees.
1. The planting, staking and maintenance of trees in the advanced nursery
stock category shall be carried out in accordance with the relevant provisions
of BS 4043.
2. The preparation, planting and securing of semi-mature trees shall be
carried out in accordance with the relevant provisions of BS 4043 and their
subsequent maintenance shall comply with BS 5837.
3. Tree surgery, repair work, bracing and feeding, and tree removal shall be
carried out in accordance with the relevant provisions of BS 3998.
4. Measures to protect and preserve existing trees to be retained on the Site
shall be taken in accordance with the relevant provisions of BS 5837.
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3.10.5 (A)
The Contractor shall not fell any tree unless expressly
identified in the Contract or Particular Specification. If
required, the Contractor shall obtain all necessary Local
Authority approvals except where otherwise provided for in
the Contract.
3.10.6 (A)
The Contractor shall comply with NJUG Publication Volume 4
‘Guidelines for the Planning, Installation and Maintenance of
Utility Services in Proximity to Trees’. In addition, S1.10.2 of
the Specification for the Reinstatement of Openings in the
Highway suggests that the use of tree root barriers may be
considered, and that specialist advice from an Arboriculturist
should be sought.
3.11 REINSTATEMENT IN HIGHWAYS AND ROADS USING FOAMED
CONCRETE
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1. Reinstatement of openings in highways and roads using foamed concrete
shall comply with the British Cement Association ‘Foamed Concrete - A
Specification for Use in Reinstatement of Openings in Highways’.
2. Reinstatement of openings in highways and roads using foamed concrete
shall comply with:
(a) The ‘Manual of Contract Documents for Highways Works – Volume 1 Specification for Highway Works’ Clause 1043; and
(b) The ‘Specification for the Reinstatement of Openings in Highways’ issued
by the Highways Authorities and Utilities Committee.
3. The pipe surround material shall be protected from the foam concrete by
an impermeable layer.
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3.11.4 (A)
The method and materials used for reinstatement of openings
in highways and roads using foam concrete shall be agreed
with the Employer.
3.12 LAND DRAINS
(i) Any special requirements necessary
to facilitate the restoration of land
drainage should be described in the
Contract.
1. The positions of all land drains intercepted, disturbed or reinstated shall
be prominently marked at every point of intersection with the work. Records
shall be kept of positions, depths, pipe diameters and the types of
construction, and a copy of these records shall be given to the Client. Care
shall be taken to prevent the disturbance of markers.
2. Prior to the permanent reinstatement of land drainage, existing drains,
where intercepted by excavations, shall be cleared. Facilities shall be
afforded to the Client and the landowner or occupier to inspect them and to
determine the extent of replacement that may be necessary.
3. The backfill of intercepting excavations shall be compacted in 200 mm
layers, to give a firm bearing immediately before replacement pipes are laid,
and shall be brought up to the level of the underside of the land drains or of
any support to be provided.
4. The affected land drains shall be cut back into firm ground until, in each
case, a section is exposed which is unaffected by the Works.
5. Replacement pipes or support beams shall bear on undisturbed ground
for at least 500 mm at each end. The replacement pipes shall be of the same
internal diameter as the sections of drain which they replace and shall be
properly connected at each end.
3.13 FILLING ABOVE GROUND
(i) This is a general Clause to cover
filling which performs no specific loadbearing or structural role. A more
thorough
specification
may
be
necessary in other cases (see, for
instance, the Highways Agency’s
‘Specification for Highway Works’).
1. Embankments and other areas of fill shall be formed of suitable materials
capable of normal compaction to form a stable fill, deposited and compacted
as soon as practicable after excavation, in layers of thickness appropriate to
the compaction plant used.
2. The filling shall, where practicable, be built up and compacted evenly, and
shall be maintained at all times with a sufficient camber or cross fall and a
surface sufficiently even to enable surface water to drain readily from it.
3.14 BLASTING
(i) It may be necessary for the Contract
to describe safe values for vibrational
amplitude and peak particle velocity.
(ii) For further guidance on blasting with
respect to tunnelling works, see British
Tunnelling Society and Institution of Civil
Engineers ‘Specification for Tunnelling’,
Clause 309.
1. The procedure for using explosives shall be stated in the Contract.
2. Where blasting is proposed adjacent to a building or other structure,
existing or under construction, the agreed safe values of vibrational
amplitude and peak particle velocity shall not be exceeded.
3. The use of electrical detonators in the vicinity of static and mobile radio
transmitters, including normal radio and television broadcasting stations and
radar units associated with aircraft movements, shall comply with the
provisions of BS 6657.
4. The handling, transport and use of explosives shall be in accordance with
the relevant provisions of BS 5607. Explosives shall be used in the quantities
and manner recommended by the manufacturer.
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3.15 PILING
(i) The ICE ‘Specification for Piling and
Embedded Retaining Walls’ includes
‘Associated Guidance on Contract
Documentation and Measurement’.
1. The Specification for piling shall be the ‘Specification for Piling and
Embedded Retaining Walls’, published by the Institution of Civil Engineers in
1996.
3.16 DEMOLITION
(i) Any further information required
should be stated in the Contract.
1. Demolition shall be carried out in accordance with BS 6187.
(ii) Reference should be made to The
Health and Safety Executive guidance
on demolition works (www.hse.gov.uk).
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3.17 (N)
HEDGES
3.17.1
Where hedges are reinstated these shall be protected and
maintained by the Contractor until established.
3.17.2
The Contractor shall give notice to the local planning authority
on behalf of the Employer, in respect of the 1997 Hedgerow
Regulations, for the removal of the hedges detailed in the
Contract or Particular Specification.
3.17.3
All working methods must be arranged in order to minimise
the lengths of hedgerows to be removed. All hedgerows shall
be reinstated to the requirements of BS 4428 and 5837 and
shall be protected and maintained by the Contractor until
established.
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3.18 (N)
PRIVATE ROADS
3.18.1
The Contractor shall consult, negotiate and agree directly with
the Street Managers the permanent reinstatement
specification of surfaced private roadways. Alternatively the
Contractor shall use an appropriate reinstatement method as
specified in the HAUC “Specification for the Reinstatement of
Openings in Highways”. Final surface materials shall be
chosen to match existing finishes as closely as possible.
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3.19 (N)
REINSTATEMENT OF DEFECTS
3.19.1
Reinstatement defects identified by the Street Authority are
sent electronically to the Employer’s Noticing System. The
Contractor shall monitor the Employer’s Noticing System for
these notices.
3.19.2
The Contractor shall comply with Code of Practice for
Inspections in all respects.
3.19.3
The Contractor shall investigate the defect where appropriate
with the highways inspector. The contractor shall contact the
street authority by the end of the next day following receipt of
the defect. Any rejected defect must be agreed by the
Contractor with the Street Authority inspector who shall sign
to confirm the Contractor is not responsible for the defect. The
Employer shall be informed of the rejection of a defect by
entry of a comment on the Employer’s Confirm system.
3.19.4
Where neither acceptance, dispute nor rejection of a defect is
received by the Employer within 7 working days the Employer
shall deem that the defect has been accepted by the
Contractor by default and shall then be liable for correcting
the defect and for any fees relating to such defects.
3.19.5
The Employer shall be given notice of any joint inspection
meeting arranged by the Contractor with the Street Authority.
The Contractor must record the following in Confirm Street
Works against the NRSWA Referral:
(i)
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That a defect has been reported by the Street Authority;
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Dates of any meetings with the Street Authority;
Names of Contractor and Street Authority personnel
attending the meeting and immediately after such a
meeting; and
The agreed action to rectify the defect.
Any remedial Works carried out will be subject to the full
inspection process and the Contractor shall be responsible for
the new guarantee period, irrespective of the date of issue of
any certificate of substantial completion or defects correction
certificate relating to that part of the Works. Guarantee
periods commence from the date of receipt of the registration
of completed Work by the Street Authority.
3.19.6
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3.19.7
Reinstatements which pose a danger to users of the street
can be identified by the Street Authority, Police or others.
When the Contractor is not on Site, the Street Authority may
first make the Site safe, and then notify the Employer (by
telephone or fax) that repair must be carried out within 2 or 4
hours. The Employer shall notify the Contractor of the details
and gain the commitment to respond within the prescribed
timescales. The Contractor shall notify the Street Authority
once the rectification works are completed. If the Contractor
is on Site, the Street Authority will instruct the necessary
remedial Work immediately and a defect notice will follow.
3.19.8
Where the Contractor does not meet the required levels of
performance over a 3 month period in an individual Street
Authority area, an informal improvement notice shall be
issued by the Employer. The informal improvement notice will
be in accordance with the improvement plan in the Code of
Practice.
3.19.9
The Contractor shall be liable for all costs and expenses
incurred by YWS as a result of the informal improvement plan.
3.19.10
The Contractor shall be liable for all fees relating to defects
which have been issued by the Street Authority.
3.20 (N)
REINSTATEMENT OF PRIVATE LAND
3.20.1
Proposals for reinstatement shall be discussed and agreed
with the landowner or landowner’s agent prior to any work
commencing. Generally, the Contractor shall offer a standard
equivalent to the HAUC “Specification for the Reinstatement
of Openings in Highways” The Contractor shall explain the
consequences of the Works, including, potential surface
reinstatement, colour match, and any potential unavoidable
damage to the surrounding surface or garden area.
3.20.2
Reinstatements shall match the existing type and colour,
unless otherwise agreed with the landowner or landowner’s
agent. In the event of Special surface materials, the
reinstatement shall restore, subject to material availability, to
an equivalent standard as the existing.
3.20.3
The Contractor shall seek advise from the Employer where
the landowner or landowner’s agent is dissatisfied with the
Contractor’s proposals, or in circumstances where the
landowner or landowner’s agent is requesting additional
works.
3.20.4
Concrete and modular driveways and footways shall be
reinstated to no less than the existing standard. Any
damaged modules due to the Contractor’s works shall be
replaced. Where insufficient modules remain for
reinstatement use and identical replacements are no longer
available, then a reasonable similar colour, shape and size
shall be used in agreement with the customer.
3.20.5
The primary objective when undertaking work in private land
(driveways, footways, lawns, gardens etc) is to ensure that
the Contractor’s reinstatements are complete, as soon as
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practicable (preferably the same day) to a consistently high
quality and to the satisfaction of the customer.
3.20.6
Where the Contractor is to work in a surface which is
structurally defective and he believes that the works may
cause unavoidable damage to the surrounding area or the
customer may be dissatisfied with the likely mis-match
between existing surfaces and new reinstatement, he should
photograph the area of the works prior to work commencing
and discuss the potential mis-match with the Customer.
Should the Contractor after discussion with the customer still
believe the customer will be unhappy with the finished Job, he
should contact YWS and agree on any specific action to be
taken.
3.21 (N)
REINSTATEMENT OF SURFACE FEATURES
3.21.1
Where an existing surface feature is removed for construction
of the Works it shall, where practicable, be preserved on Site
for final reinstatement.
3.21.2
Where new items are required to replace those removed, or
damaged during construction of the Works, these shall be of
equivalent quality to those removed.
3.22 (N)
SIGNING/LIGHTING/GUARDING
3.22.1
The Contractor shall comply with the Code of Practice for
Inspection of Roads and Streetworks in all respects.
3.22.2
Signing / Lighting / Guarding defects identified by the Street
Authority or YWS auditors will be telephoned into the
Employer and logged electronically. The contractor shall
record on the system the response time and the team
responsible for the defect.
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3.23 (N)
UNMADE ROADS
3.23.1
Backfill and reinstatement of unmade roads and tracks shall
comprise backfilling above the level of the pipe or apparatus
surround with suitable filling material to within 250mm of the
original surface. This shall be followed by a 250mm thickness
of Type 1 granular sub-base material adequately compacted
and blended into the existing surface.
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3.24 (N)
WALLS
3.24.1
Where walls are to be broken out, or taken down, every
precaution shall be taken to ensure that adjoining sections of
wall are not damaged or made unsafe.
3.24.2
Reconstruction shall match the existing walls in all respects
including the provision of any additional materials that may be
necessary.
3.24.3
Where stone walls are taken down, the stone shall be stacked
on one side for re-use.
3.24.4
Where the Contractor has to pass under or work near walls,
care must be taken not to disturb the foundations of the walls.
If any disturbance or damage to the wall is made, the
Contractor shall be responsible for correcting the disturbance
or damage.
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Section 4 – Concreting and Formwork
SECTION 4
CONCRETING AND FORMWORK
The Notes for Guidance are not part of
the Specification.
4.1 SUPPLY OF INFORMATION
1. Before any concrete is supplied and not less than 7 days before the start
of the concrete production, all pertinent information specified in BS EN 2061:2016 Clause 7.2 and BS 8500-2:2015+A1:2016 Clause 5.2 shall be
exchanged and agreed with the Producer.
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4.1.2 (A)
The above information shall be retained by the Contractor,
and shall be available for inspection, until submitted to the
Employer for his records.
4.2 INITIAL TESTING
(i) Where it is not practicable to carry out
full-scale trials, special reference should
be made in the Contract to laboratoryscale mixes.
1. Initial testing shall be undertaken for each classification of structural
concrete.
2. Such testing shall be in accordance with BS EN 206-1: 2013+A1:2016
Clause 9.5, Clause 10 and Annex A.
(ii) Sufficient information should be
derived from the initial testing to ensure
that the concrete will meet the specified
requirements. It may also be necessary
to specify water absorption tests for
structures designed to retain an aqueous
liquid.
4.3 IDENTITY TESTING
1. Where identity testing is specified for the testing of slump, flow and air
content of individual batches, it shall be undertaken in accordance with BS
8500-1.
2. Where specified, identity testing for strength shall be carried out in
accordance with Clause 2.20.5.
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CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
4.3.3 (A)
For every structural pour, the first batch of concrete shall be
sampled and tested. Thereafter further random samples shall
be taken and tested at an average rate not less than that
specified in Clause 2.20.5. Non-structural concrete shall be
sampled and tested at a minimum rate of one per every
100m³ or once per week, whichever is the higher rate.
4.3.4 (A)
All sampling and testing of concrete for conformity shall be in
accordance with BS EN 12350 and BS EN 12390 or other
agreed standard.
4.3.5 (A)
Samples from concrete placed by pumping shall be taken
from the delivery chute of the concrete mixer prior to pumping.
4.3.6 (A)
Four cubes shall be made from each sample of concrete
taken for testing; one cube shall be made for testing at 7 days,
two for testing at 28 days and one reserved for further testing
should it be found to be necessary, at any other age. All cubes
shall be clearly marked with a reference number. The
Contractor shall make appropriate arrangements for the
transfer of cubes to the laboratory for testing.
4.3.7 (A)
The Employer may require tests on any suspect hardened
concrete to be carried out and assessed in accordance with
BS EN 12390 and BS EN 13791. The action to be taken in
respect of concrete, which fails to meet the requirements of
the Specification, shall be agreed with the Employer.
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4.3.8 (A)
Section 4 – Concreting and Formwork
Copies of all the concrete cube test results shall be retained
by the Contractor for inspection until submitted to the
Employer for his records, and any failures shall be notified.
4.4 POROUS NO-FINES CONCRETE
1. The concrete shall not be mechanically vibrated or excessively worked
when placed.
4.5 TRANSPORTING, PLACING AND COMPACTING
(i) Any requirements for placing concrete
in special sequence, e.g., by alternate
bay construction, should be described in
the Contract.
(ii) “Adequate” in the context of notice to
the Client should be sufficient time to
allow the Client to fulfil their quality
management obligations. The minimum
time period should be agreed at the
commencement of the Contract.
(iii) Any variations to the times in Clause
4.5.3 should be specified in the Contract.
(iv) Any requirements for testing fresh
concrete should be specified as in
Clause 2.20.5.
1. Concrete shall be transported from the mixer in accordance with BS 85002 and placed in the Works as rapidly as practicable, by methods which will
prevent the segregation or loss of any of the ingredients and will maintain
the required consistency. It shall be deposited, as nearly as practicable, in
its final position and all equipment for transporting concrete shall be kept
clean.
2. Adequate notice shall be given to the Client of the intention to commence
concreting.
3. Concrete shall be delivered to Site within the times specified in Clause
14.2 of BS 2015+A1:2016.
4. Concrete shall be thoroughly compacted in its final position within 30
minutes of commencing discharge. The plant used for compaction shall be
operated continuously during the placing of each batch of concrete until the
expulsion of air has virtually ceased, and in a manner which does not
promote segregation of the ingredients.
5. Whenever vibration has to be applied externally, the design of formwork
and disposition of vibrators shall be such as to ensure efficient compaction
and to avoid surface blemishes.
Yorkshire Water Services Ltd additional,
new or substitute clauses
4.5.6 (A)
For all pours other than those of less than 1 m³, the Contractor
shall give the Employer 24 hours’ notice of his intention to
place concrete, unless agreed otherwise.
4.5.7 (A)
Concrete shall not be placed in any pour without the consent
of the Contractor’s Representative, recorded on an approved
form. The Contractor’s Representative shall certify that all
aspects of the proposed pour have been properly checked
and approved prior to concreting.
4.5.8 (A)
The Contractor shall submit details of his proposals for
transporting and compacting concrete for approval at least 7
days before concreting operations commence.
4.6 CONCRETING IN COLD WEATHER
(i) For further information see ‘Winter
Concreting’, published by Concrete
Information Ltd in 1985.
1. Concreting at ambient temperatures below 2°C may be carried out only if
the following conditions are met:
(a) the aggregates and water used in the mix shall be free from snow, ice
and frost;
(b) before placing concrete, the formwork, reinforcement and any surface
with which the fresh concrete will be in contact shall be free from snow, ice
and frost and shall be at a temperature above 0°C;
(c) the initial temperature of the concrete at the time of placing shall be at
least 5°C as defined in BS EN 206-1:2013+A1:2016, Section 5.2.8 Lower
Limit;
(d) the temperature at the surface of the concrete shall be maintained at not
less than 5°C at any point until the concrete reaches a strength of 5 N/mm2,
as confirmed by tests on cubes matured under similar conditions; and
(e) temperatures at the surface of the concrete shall be measured where the
lowest temperature is expected.
2. Precautions shall be taken to prevent the temperature of any concrete
falling to 0°C during the first five days after placing.
CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
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4.7 CONCRETE TEMPERATURE
(i) The Contract should specify a
reduced upper temperature if the design
of the structure requires a lower
temperature, i.e., to minimise thermal
cracking on large pours.
1. The resultant temperature of the combined materials in any batch of
concrete at the point and time of delivery to the Works shall not exceed the
upper limit as stated in BS 8500-2. Cement shall not be permitted to come
into contact with water at a temperature greater than 60°C.
2. Where the temperature of the fresh concrete is likely to exceed that
specified in Clause 4.7.1, concreting shall not be permitted unless stated in
the Contract.
4.8 CURING
(i) Consideration may have to be given
to measures to prevent thermal cracking
where a temperature differential in
excess of 20°C is likely to occur, e.g., by
extending striking times for the
formwork.
1. Curing of concrete shall be carried out in accordance with BS EN 13670
Curing Class 2.
Yorkshire Water Services Ltd additional,
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4.8.4 (A)
The Contractor shall submit details of his proposals for curing
for approval at least 7 days before concreting operations
commence.
4.8.5 (A)
Before use in the works, the Contractor shall submit full
details of the proposed chemical curing agent for approval.
4.8.6 (A)
All compounds shall be pigmented to indicate effective
coverage.
4.8.7 (A)
When chemical curing agents are used on flat slabs, agents
containing reflective aluminium pigment shall be used.
4.8.8 (A)
Compounds shall have an efficiency rating of at least 90%
when tested in accordance with Clause 1027 of the
Department of Transport Specification for Highway Works.
4.8.9 (A)
Where used in contact with water under preparation or
conveyance for public water supply the curing agent shall
comply with Clause 2.1 of this specification.
2. In cold weather, when the temperature of freshly-placed concrete may
approach 0°C, cold water curing shall not be employed.
3. Components which are intended to have a similar exposed surface finish
shall be cured in the same manner.
4.9 RECORDS OF CONCRETING
1. Up-to-date records of the dates and times when concreting is carried out,
and of the weather and temperatures at those times, shall be kept. The
records shall be available for inspection.
2. Sufficient records shall be maintained to enable every batch of concrete
and its location within the Works to be identified.
4.10 CONSTRUCTION OF FORMWORK
(i) BS 5975 gives recommendations as
to standards of good practice in
formwork construction.
(ii) The positioning and detailing of
movement joints should be described in
the Contract.
(iii) Any special conditions relating to the
re-use of forms, insofar as the materials
of construction and repairs between
uses may affect the colour and surface
finish of exposed surfaces, should be
described in the Contract.
(iv) Any special requirements regarding
chamfers to internal angles should be
described in the Contract.
CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
1. Formwork shall be sufficiently rigid and tight to prevent loss of mortar from
the concrete and to maintain the correct position, shape and dimensions of
the finished work. It shall be so constructed as to be removable from the cast
concrete without shock or damage.
2. The forms shall be capable of producing a consistent quality of surface,
as described in the Contract.
3. Where holes are required in forms to accommodate projecting
reinforcement, fixing devices or other built-in items, precautions shall be
taken to prevent loss of the mortar matrix.
4. Formwork shall give access for the preparation of joint surfaces before the
concrete has hardened.
5. For the purposes of compliance with the provisions of Clause 4.12.3, the
method of constructing formwork shall allow for props to soffit forms to
remain in position continuously for the period described.
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6. All exposed vertical and horizontal edges of concrete shall have 25 mm x
25 mm chamfers. Chamfers shall extend to 150 mm below finished ground
level.
4.11 CLEANING AND TREATMENT OF FORMS
1. The interiors of all forms shall be thoroughly cleaned out before any
concrete is placed. The faces of the forms in contact with the concrete shall
be clean and treated with a suitable release agent, where applicable.
2. Where a concrete surface is to be permanently exposed, only one release
agent shall be used throughout the entire area. Release agents shall be
applied evenly and contact with reinforcement and other embedded items
avoided. Where the concrete surface is to receive an applied finish, care
shall be taken to ensure the compatability of the release agent with the finish.
Yorkshire Water Services Ltd additional,
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4.11.3 (A)
Before use, the Contractor shall submit full details of the
proposed formwork release agent for approval.
4.11.4 (A)
Where used in contact with water under preparation or
conveyance for public water supply the formwork release
agent shall comply with Clause 2.1 of this Specification.
4.12 STRIKING OF FORMWORK
(i) As the removal of formwork is
dependent upon the method of working,
the Contract may state a formal
procedure for determining striking times,
based on CIRIA Report R136.
(ii) Interpretation of CIRIA Report R136
should be in accordance with the
following:
(a) for members with “Rough finish”, the
requirements applicable to F1 and F2
finish apply.
1. Formwork shall be removed without shock to, or disturbance of, the
concrete.
2. Formwork to vertical surfaces or sloping formwork not supporting concrete
in flexure shall not be removed until the concrete strength shall be sufficient
to meet any wind loading upon the concrete likely to arise at the time when
the formwork is removed, and:
(a) the concrete strength (as confirmed by tests in cubes cured under
representative conditions) has reached 5 N/mm2; or
(b) for concrete containing cement to BS EN 197-1:2011 CEM I 42.5, 52.5
only, in the absence of cube test results, a minimum period shall have
elapsed since the concrete was poured equivalent to 11 hours at 15°C for
unsealed plywood forms or 8 hours at 15oC for impermeable forms.
(b) for members with “Fair finish” or “Fair
worked finish”, the requirements
applicable to F3 and F4 finish apply.
3. Formwork supporting concrete in flexure shall not be removed until:
(iii) “Rough finish”, “Fair finish” and Fair
worked finish” are described in Clause
4.22 (i).
(a) the concrete strength (as confirmed by tests on cubes cured under
representative conditions) has reached 10 N/mm2, or twice the stress to
which the concrete will then be subjected, whichever is the greater; or
(b) for concretes containing cement to BS EN 197-1:2011 CEM I 42.5,
52.5, in the absence of cube test results or any formal procedure agreed in
writing, the periods before striking calculated from the relevant formula
given in the following table shall be used.
Type of Formwork
Soffit forms to slabs and beams
Props to slabs and beams
(iv) It should be noted that 11 hours at
15°C is equivalent to:
8 hours at 20°C
15 hours at 10°C
24 hours at 5°C
8 hours at 15°C is equivalent to:
6 hours at 20°C
12 hours at 10°C
18 hours at 5°C
(v) Any requirement for the control of
thermal cracking should be described in
the Contract.
CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
Period Calculated for Mean Ambient
Temperature (t) Between 0°C and
25°C Using Formulae Below
_100__ days
t + 10
_250__ days
t + 10
4. For concrete containing cement not conforming to BS EN 197, the times
for striking of formwork shall be derived from CIRIA Report R136.
5. Sufficient records to identify the time from pouring of any section to the
striking of the formwork on the same shall be maintained on Site for
inspection.
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4.13 SLOPING FORMWORK
(i) Any requirement for top formwork at
slopes flatter than 30° to the horizontal
should be described in the Contract.
1. Top formwork shall be provided to slopes 30° or more from the horizontal,
except where placing and compaction can achieve the specified surface
finish without top formwork.
4.14 CUTTING AND BENDING OF REINFORCEMENT
(i) The Contract should detail any
particular requirements for dealing with
health and safety issues in connection
with starter bars and the fixing of
reinforcement, as a result of any
designer’s risk assessment.
1. Cutting and bending of reinforcement shall be in accordance with BS
8666.
2. Except for the use of proprietary starter bar systems, reinforcement shall
not be straightened or re-bent. When using proprietary systems and bending
projecting reinforcement, care shall be taken not to damage the concrete
and to ensure that the radius is not less than the minimum specified in BS
8666.
4.15 FIXING OF REINFORCEMENT
(i) Where the use of proprietary
reinforcement continuity systems, rolled
mats, mesh or couplers is proposed as
an alternative to the reinforcement
detailed on the Contract Drawings, this
could require a variation from the
Contract.
1. Reinforcement shall be firmly supported and secured against
displacement, in accordance with BS 7973-2.
2. Non-structural connections for the positioning of reinforcement shall be
made with tying wire or other fixing devices. Projecting ends of ties or clips
shall not encroach into the concrete cover.
3. Concrete cover shall not be less than the nominal cover minus 10 mm or
greater than the nominal cover plus 15 mm (Δc in BS 8500-1:2015+A1:2016
A3). Unless shown otherwise on the drawings, nominal cover shall be:
(a) 45 mm for tops of walls;
(b) 50 mm for concrete cast against blinding;
(c) 75 mm for concrete cast against soil; and
(d) 40 mm for all other locations.
4.16 SURFACE CONDITION OF REINFORCEMENT
(i) Any protection required for steel left
projecting should be described in the
Contract.
1. Concrete shall not be placed until reinforcement is free from any
substance which might adversely affect the steel or concrete chemically, or
reduce the bond.
4.17 LAPS AND JOINTS
1. Laps and joints in reinforcement shall be made only at the positions
described on the Drawings.
4.18 WELDING OF REINFORCEMENT
1. Reinforcement shall not be welded on site except where described in, or
permitted under, the Contract. All welding procedures shall be stated in the
Contract.
CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
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4.19 BUILT-IN ITEMS
(i) Some coatings may not provide good
adherence to concrete and, therefore,
may require additional sealing systems
and/or features to ensure a sound
mechanical key to the concrete structure
The fittings should be designed to avoid
formation of air pockets or voids during
the placing/compaction of concrete.
1. Where pipes, sleeves, water bars or other items are designed to be cast
into concrete, they shall be constructed and installed in order to ensure that
they are:
(a) securely and rigidly retained in position;
(b) watertight for the design life of the fittings and structure;
(c) resistant to corrosion for the design life;
(d) adequately bonded to the concrete; and
(e) free from external coatings that may reduce the bond.
2. Precautions shall be taken to prevent the formation of air pockets, voids
or other defects whilst the concrete is being placed.
4.20 CONSTRUCTION JOINTS
(i) Guidelines on the control of cracking
can be found in CIRIA C660 ‘Early-age
Thermal Crack Control in Concrete’.
(ii) Proprietary systems may be available
for this application.
1. Position and details of construction joints in concrete shall be described
in the Contract.
2. Joint lines shall be arranged to coincide, wherever possible, with features
of the finished work.
3. Concreting shall be carried out continuously up to construction joints.
4. Concrete shall not be allowed to taper off to a thickness of less than
50 mm. Vertical joints shall be formed against a stop board, suitably notched
to accommodate the reinforcement. The top surface of each lift of concrete
shall be straight and level.
5. Where a kicker is used, it shall be at least 70 mm high and shall be cast
integrally with the slab.
6. The surface of any concrete against which new concrete is to be cast shall
be free from laitance and shall be roughened to the extent that the large
aggregate is exposed but not disturbed. The joint surface shall be cleaned
immediately before the fresh concrete is placed against it.
7. Where practicable, such preparation of joints shall be carried out when
the concrete has set but not hardened.
4.21 SURFACE FINISHES PRODUCED WITHOUT FORMWORK
(i) The four finishes are intended to be
applied as follows:
(a) Screeded - surfaces to receive
further treatment or of no visual merit, or
expressly suitable to their function with
the workmanship as specified;
(b) Wood Float - surfaces where a
reasonably regular finish is required but
appearance is not of prime importance;
(c) Steel Trowel - surfaces where
appearance is important; and
(d) Power Float Finish - surfaces where
a smooth flat finish with only minor
deviations is required.
(ii) Any other required finish should be
described in the Contract.
Yorkshire Water Services Ltd additional,
new or substitute clauses
CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
1. The concrete shall be levelled and screeded to produce a uniform plain or
ridged surface, as required. No further work shall be applied to the surface
unless it is a first stage for a wood float or steel trowel finish.
2. The screeded finish shall be wood floated under light pressure to eliminate
surface irregularities.
3. When the moisture film has disappeared and the concrete has hardened
sufficiently to prevent laitance from being worked to the surface, the surface
to the wood float finish shall be steel-trowelled under firm pressure to
produce a dense, smooth, uniform surface free from trowel marks.
4. Power floating shall be undertaken by steel floating the concrete to an
even finish with no ridges or steps. When the concrete has taken a primary
set, it shall be power trowelled to a uniform smooth polished surface free
from trowel marks or other blemishes. Once power floating is completed, the
surface finish must be adequately protected from construction traffic.
5. Where the type of finish is not given, it shall be wood float finish.
4.21.6 (A)
All concrete surfaces, which retain liquids, shall, where
practicable, have a Power Float Finish. Where not
practicable, the finish shall be Steel Trowel Finish. The roofs
of tanks shall have a Steel Trowel Finish.
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4.22 SURFACE FINISHES PRODUCED WITH FORMWORK
(i) The three types of surface finish are
intended to be applied as follows:
(a) Rough - surfaces next to earth, or to
receive further treatment, or of no visual
merit, or expressly suitable to their
function with workmanship, as specified;
(b) Fair - surfaces required for
serviceability and structural soundness
and which are not visually important; and
(c) Fair worked - aqueous liquid retaining
faces and other surfaces to good quality
concrete, required for serviceability,
structural soundness and appearance.
1. Rough finish shall be obtained by the use of moulds or properly designed
forms of closely-jointed sawn boards. The surface shall be free from
substantial voids, honeycombing or other large blemishes.
2. Fair finish shall be obtained from forms designed to produce a hard
smooth surface with true, clean arrises. Only very minor surface blemishes
shall be permitted and there shall be no staining or discolouration. Any
projections shall be removed and the surface made good.
3. Fair worked finish shall be obtained by first producing a fair finish and then
filling all surface blemishes with a fresh, specially prepared cement and fine
aggregate paste whilst the concrete is still green, where possible. After the
concrete has been properly cured, the faces shall be rubbed down, if
required, to produce a smooth and even surface. If the surface is to be
exposed in the final work, every effort shall be made to match the colour of
the concrete.
(ii) If test panels are required, these
should be described in the Contract.
(iii) CIRIA report C511 gives guidance on
the type of CPF liners and their use.
4. Liquid retaining surfaces and other surfaces exposed in the completed
Works shall receive a fair worked finish. All other structural concrete surfaces
shall receive a fair finish.
5. The use of controlled permeability formwork (CPF) shall be agreed with
the Client. The CPF liner shall have the following minimum improvements to
the outer 20 mm of the concrete:
a) cement content of 75 kg/m3 greater than the control; and
b) a minimum improvement of 50% for surface tensile strength, ISAT
carbonation and chloride ingress.
6. The CPF liner shall be installed and used in accordance with the
manufacturer‘s recommendations. Release agents shall not be used.
Type III, CPF liners can be reused, subject to agreement with the Client.
Yorkshire Water Services Ltd additional,
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4.22.7 (A)
Good finish shall be obtained from forms designed to produce
a hard, smooth surface of uniform colour, texture and
appearance, with true clean arises, and constructed so as to
leave no marks or steps, to allow no grout loss, and to
minimise blowholes. Only very minor surface blemishes will
be permitted and there shall be no staining or discolouration.
Joints between panels and holes for shutter ties shall form a
neat regular pattern throughout the structure. Any noticeable
blow-holes and other surface blemishes shall be infilled with
a freshly and specially prepared matching cement and fine
aggregate paste to the same proportions as the base
concrete whilst the concrete is still green. The concrete
surface shall only be rubbed down where necessary to
remove any fins and other projections.
4.22.8 (A)
All internal concrete faces retaining water under preparation
or conveyance for public water supply shall have a “Good
Finish” to 4.22.7 above, unless otherwise stated.
Additional Note:
Replace “three types” with “four types”
in guidance note (i)
Add this description to guidance note (i)
(d) Good – internal faces of structures
containing water under preparation or
conveyance for public water supply and
other surfaces where specified to good
quality concrete, required for hygiene,
serviceability, structural soundness and
appearance.
CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
4.22.9 (A)
Structural concrete exposed to view down to a depth of
150mm below finished ground level shall have a “Fair
Worked Finish” to 4.22.7 above unless otherwise stated. For
unreinforced concrete surfaces next to earth, a "Rough
Finish" to 4.22.1 is acceptable, unless otherwise stated.
4.22.10 (A)
Should any “Special” concrete finish be required this shall be
detailed in full in the Particular Specification.
4.22.11 (A)
A trial panel shall be constructed if required in the Contract to
demonstrate the finish of the concrete in the works. The panel
shall represent a typical section of the works and shall
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incorporate as many of the different features of construction
as possible including, where appropriate:
Reinforcement detail; surface finishes - formed and
unformed; waterbar and stop-end construction; kickers;
curing methods and striking times; bolt holes and chamfers.
4.22.12 (A)
Full details of the proposed test panel shall be submitted to
the Employer and construction shall proceed as if part of the
works. Concrete shall be monitored and tested for
compliance.
4.22.13 (A)
The trial panel shall be completed to the Employer’s approval
before structural concrete is placed in the works. The
successful panel shall be retained on Site as a standard until
completion of the works and shall be removed on the
Employer’s instruction or completion of the Works. Any trial
panels, which do not meet with the approval of the Employer
shall be removed
4.23 WEARING SCREEDS
(i) The class of abrasion resistance
required should be specified in the
Contract.
(ii) Reference should be made to BS
8500-2.
1. Wearing screeds (granolithic finish) shall be provided, laid and finished in
accordance with the relevant provisions of BS 8204-2.
2. Wearing screeds shall provide abrasion resistance to class AR4/WS of
Table 4 of BS 8204-2:2003. Where high abrasion conditions are expected,
wearing screeds shall provide abrasion resistance to class AR1/WS of Table
4 of BS 8204-2:2003.
3. Where concrete benching is required to have a granolithic finish with
abrasion resistance to class AR4/WS of Table 4 of BS 8204-2:2003, this
shall be formed with four parts 8 mm to dust to one part sulphate resisting
cement placed with a steel trowel finish. Where sulphate resisting cement is
unavailable, then a combination of Portland Cement (CEM 1) and GGB FS
or PFA shall be used to give equivalent resistance to sulphate attacks.
4.24 TIE BOLTS FOR FORMWORK
1. Tie bolts shall be of the high tensile variety, fixed perpendicular to the
formwork.
2. Tie bolts shall not embed any permanent metal parts within 50 mm of the
concrete surface.
3. Voids remaining after the removal of all, or part, of each tie bolt shall be
sealed using a polymer-modified cementitious compound, or other suitable
product, unless specified in the Contract. Metal-based expansive admixtures
shall not be used. All such voids shall be prepared in accordance with the
manufacturer’s instructions, prior to filling, to ensure an adequate bond is
achieved.
4. Tie bolts which form a continuous hole through a structure designed to
retain an aqueous liquid shall not be used.
5. In the case of structures designed to retain an aqueous liquid, any other
measures securing formwork shall not impair the watertightness of the
structure.
Yorkshire Water Services Ltd additional,
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4.24.6 (A)
In the case of liquid retaining structures, removable tie bolt
systems which form a continuous hole through the structure
shall be permitted subject to satisfactory completion of
structure testing in accordance with Clause 7.14.
4.25 TOLERANCE FOR CONCRETE SURFACES
(i) The table applies to general concrete
structures. Where more stringent
tolerances are required, these should be
described in the Contract (e.g.,
measuring flumes or areas where plant
is to be installed).
CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
1.
Concrete surfaces in the final work shall have no abrupt irregularities
which are, to an extent, observable by eye. Subject to retaining the
required concrete cover to reinforcement, other deviations from the
surfaces described in the Contract shall be no more than the following
permissible amounts:
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Type of Finish
Yorkshire Water Services Ltd
additional, new or substitute clauses
Deviation From Line, Level, Vertically,
Cross-sectional Dimension or Length (mm)
Screeded or rough
10
Power float
3
Any other
5
4.25.2 (A)
For Good Finish the surface deviation from a straight
template 3 m long shall not exceed 2 mm, and contain no abrupt changes
exceeding 1 mm.
4.26 GROUT QUALITY CONTROL TESTING
(i) Grout strength requirements should
be described in the Contract.
1. Where tests are required for different properties of grout, they shall be
carried out on samples from the same batch.
(ii) Grout can alternatively be specified
by nominal mixes (see Clause 2.17).
2. The density and workability of every batch shall be determined. The
density shall not differ from the value described in the Contract by more than
5%. The workability shall not differ by more than 125 mm for the “Concrete
Flow Through Test” or 5 seconds for the “Marsh Cone Test” with 10 mm
orifice, from the values described in the Contract.
3. Sampling shall be at the rate of three cubes taken from every 5 m3 of grout
or 50 m of grouted annulus, whichever is smaller. When tested in
accordance with the relevant provisions of BS 4551, cubes shall have a
compressive strength, as given in the following table:
Grout Function
Minimum Compressive Strength at 28 Days
(N/mm2)
Annulus filling:
Type I lining
12
Type II lining
3
Exterior void filling
2
4. Cube moulds shall be 70 mm (nominal) or 100 mm, and all joints shall be
sealed to prevent leakage.
5. Moulds shall be overfilled and air bubbles removed by lightly tapping the
mould. After leaving for 30-60 minutes, the excess grout shall be struck off
and the moulds covered with plastic sheeting or damp hessian. Moulds shall
be stored at 20°C ±5°C for 24 hours or until the grout has attained sufficient
strength to allow the cube to be stripped from the mould, whichever is the
greater.
6. The cubes shall be removed from the moulds, marked, and stored in water
at a temperature of 20°C ± 1°C until tested.
7. Trial mixes of the grout type proposed shall be undertaken to establish the
properties of the grout. The amount of bleedwater shall be determined by
filling a 100 mm diameter impermeable pot to a depth of 100 mm, covered
to prevent evaporation. The bleedwater shall be removed after 3 hours. The
percentage volume of bleedwater after 3 hours (expressed as volume of
bleedwater:volume of original sample) shall not exceed:
(a) 1% for Type I linings; or
(b) 5% for Type II linings.
Yorkshire Water Services Ltd additional,
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CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
4.26.8 (A)
Cube moulds shall comply with the requirements of EN
12350-1 and be effectively sealed at the joints against
leakage.
4.26.9 (A)
A set of cubes shall consist of two cubes for testing at 28 days
plus one cube for each other required test age. All cubes in
one set shall be made from the same batch of grout.
4.26.10 (A)
Copies of all the grout cube test results shall be made
available for inspection.
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4.27 FIBRE REINFORCED CONCRETE (FRC)
(i) Polypropylene or stainless steel fibres
may be used.
1. Where concrete reinforced with synthetic polymer or stainless steel fibres
is used as an alternative to air-entrained concrete containing normal fabric
reinforcement in roads and footpaths, this shall be agreed with the Client
prior to commencement of the design.
2. Fibre reinforced concrete (FRC) shall be designed in accordance with
Concrete Society Technical Report 63, ‘Guidance for the Design of SteelFibre Reinforced Concrete’.
4.28 CONCRETE REPAIRS
1. All concrete repairs shall be undertaken in accordance with BS EN 150410. Test sections shall be required in order to determine the sufficiency and
compatibility or otherwise, of the proposed materials and methods.
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CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
4.29 (N)
SCABBLING
4.29.1
The use of scabbling as a work technique may only be
considered where low frequency tools are used and should
be avoided wherever possible so as to protect the workforce
from risks due to noise, vibration and dust. Alternative
techniques should be adopted wherever possible.
4.30 (N)
CONSISTENCE
4.30.1
The desired consistence of a concrete shall be determined by
the Contractor. The consistence expressed in terms of the
slump test to BS EN 12350-2 must correspond to the
information submitted to the Employer.
4.30.2
Concrete to be super-plasticised shall be produced to the
tolerances specified in clause 5.4.1 of BS EN
206:2013+A1:2016, prior to the addition of the admixture.
4.30.3
Any concrete, which does not comply with consistence
requirements, shall not be used in the works. A delivery truck
from an off-site plant carrying rejected concrete shall not
return to the Site within 2 hours of rejection, unless discharge
has been witnessed by the Contractor.
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Section 5 – Pipelines and Ancillary Works
SECTION 5
CONSTRUCTION OF PIPELINES AND ANCILLARY
WORKS
The Notes for Guidance are not part of
the Specification.
5.1 PIPELAYING GENERALLY
(i) The following Publications give
recommendations on standards of good
practice for the installation of pipelines on
land:
General: BS EN 14161
Ductile iron: BS 8010 Section 2.1
GRP: BS 8010 Section 2.5
Drains and sewers: BS EN 752.
(ii) Further information on installing box
culverts is available in ‘Guide to Site
Practice’, published by the Box Culvert
Association.
(iii) Marker tape is not applicable to
trenchless pipe installation.
(iv) The minimum depth of cover should
be specified in the Contract.
1. Where socketed pipes are required to be laid on a granular or sand bed,
or directly on a trench bottom, joint holes shall be formed in the bedding
material or excavated formation to ensure that each pipe is uniformly
supported throughout the length of its barrel and to enable the joint to be
made.
2. Pipes shall be laid on setting blocks only where a concrete bed or cradle
is used.
3. Where pipes are required to be bedded directly on the trench bottom, the
formation shall be trimmed and levelled to provide even bedding of the
pipeline and shall be free from all extraneous matter that may damage the
pipe, pipe coating or sleeving.
4. Any protective cap, disk or other appliance on the end of a pipe or fitting
shall only be removed permanently when the pipe or fitting which it protects
is about to be jointed. Any exposed pipe ends shall be capped when
pipelaying is not actively being carried out to prevent vermin or soil entering
the pipework.
5. Pipes and fittings, including any lining or sheathing, shall be examined for
damage and the joint surfaces and components shall be cleaned immediately
before laying. Where repairs are required, these shall be agreed with the
Client.
6. Suitable measures shall be taken to prevent extraneous material from
entering the pipe, and to anchor each pipe to prevent flotation or other
movement before the Works are complete.
7. Pipeline marker tape, in accordance with Clause 2.76, shall be laid
between 100 mm and 300 mm above the pipe. Where a tracer system is
specified, it shall be continuous and adequately secured to valves and fittings.
8. Where the gradient of the as-laid pipeline exceeds 5%, installation shall be
uphill with sockets leading.
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5.1.8 (S)
For distribution, all mains shall be laid so that they shall have
a generally continuous though not necessarily uniform rise
from each washout to air valve. Where the gradient exceeds
5% installation shall be uphill with sockets leading.
5.1.9 (A)
Deleted
5.1.10 (A)
The future of decommissioned pipes shall be determined by
the Employer.
5.1.11 (A)
The minimum depth of cover at which a main is laid will be
dictated by the diameter and surface construction (see Table 1
below), in all instances, consideration needs to be given to
ensure the integrity of the asset being installed therefore all
pipelines should be risk reviewed in accordance with although
not limited to the following:
All mains installed in the carriageway should consider wheel
and point loads while complying with the Specification for the
Reinstatement of Openings in Highways code of practice
(SROH)
In fields which are likely to be ploughed or subject to other
agricultural activities (e.g. subsoiling) the designer should
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Section 5 – Pipelines and Ancillary Works
consider the risk on a site by site basis taking into account
all relevant factors and if appropriate the minimum cover
should be increased to a depth sufficient to minimise the
risk of damage from such activities.
Special crossings including other infrastructure assets such
as strategic YW assets, railway lines, motorways,
structures, Oil or major Gas pipelines etc. while also
complying with the asset owners expectations.
All mains installed should be at a depth which allows the
installation of chamber covers & frames without interfering
with the fitting housed within, and prevents valves and
fittings, including covers and frames, from sitting proud of
the finished ground level.
Minimum Depths of Cover to Mains
Table 1: Surface construction / minimum depth of cover to mains
Agricultural
land including
open fields
Grassland
including rural
and urban
verges
Type 3/4 Rural / Suburban
highways including
secondary / minor roads
and footways
Type 2 Urban
highways and
above
Services up to and
inclusive of 50mm
(2”)
750mm
750mm
750mm
750mm
Small Diameter
network mains
63mm – 200mm (8”)
900mm
750mm
750mm
900mm
Large diameter
mains 200mm and
above
900mm
900mm
900mm
900mm
Diameter range
5.1.12 (A)
Deleted
5.1.13 (A)
Final line and levels are to be determined on Site to suit Site
conditions, including topography and existing services.
5.1.14 (A)
In making connections to the existing water distribution
network the Contractor shall always consider non-intrusive
and non-disruptive techniques as the preferred method.
5.1.15 (A)
Where undertaking works on behalf of the Developer the
Contractor shall obtain written confirmation from the
Developer prior to commencing installation works in respect of
line and levels.
5.1.16 (A)
For works on Developer sites the installation of potable water
mains within ducts is not acceptable as this impedes
maintenance and repair. Where required, the Contractor shall
provide and fix a PVC duct through which a service can be laid
immediately or at a later date.
5.1.17 (A) The Contractor should at all times consider laying services using
the most cost effective method including minimum dig techniques such as
moling.
5.2 PIPE BEDDING
(i) When puddled clay stanks are
required, these should be described in
the Contract.
CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
1. Bedding for pipes shall be constructed by spreading and compacting
granular bedding material over the full width of the pipe trench. After the pipes
have been laid, additional material shall, if required, be placed and
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(ii) Details of pipe bedding, surround and
sidefill should be described in the
Contract.
(iii) Refer to BS EN 1295-1 for pipe
bedding design details.
Section 5 – Pipelines and Ancillary Works
compacted equally on each side of the pipes and, where practicable, this shall
be done in sequence with the removal of the trench supports.
2. Where specified in the Contract, stanks shall be constructed in the pipe
trench to inhibit the flow of groundwater along the granular bedding and pipe
surround. Stanks shall be formed around pipelines on either side of stream
crossings.
3. The stanks shall be constructed of either clay, which shall be puddled,
placed, and compacted around the pipe, or a lean mix concrete which shall
be placed and compacted around the pipe, over a length specified in the
Contract. The requirement in both cases is that the stank shall surround the
pipe to the bottom and to the full width of the excavated trench to form a
barrier within the granular bed and surround and protrude into the backfill
material above by an amount specified in the Contract.
4. In bad ground conditions where the migration of the pipe granular surround
into the ground may occur, the surround shall be wrapped in geotextile
membrane.
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5.2.5 (A)
Where the bottom of the excavation is not sufficiently firm and
stable to provide a suitable bed for the pipe or fitting, the
Contractor shall excavate below the final surface until a firm
foundation is reached and the excavation shall be filled up to
the final surface with imported material.
5.2.6 (A)
Pipe bed and surround for GRP pipes should be designed to
match pipe properties in accordance with the manufacturer’s
specification.
5.2.7 (A)
Structural design of buried polyethylene pipelines and the
trench conditions including bed surround and backfill
compaction should be validated in accordance with IGN 4-3218.
5.2.8 (A)
Material for pipe bedding shall be approved by the Employer
5.3 CONCRETE PROTECTION TO PIPES
(i) Rapid hardening cement should not be
used in concrete for the protection of
plastics pipes.
1. Pipes to be bedded on, or cradled with, concrete shall be supported on
precast concrete setting blocks, the top face of each block being covered with
two layers of compressible packing, in accordance with Clause 2.19.
(ii) Plastics pipes should be wrapped with
a layer of plastic sheeting complying with
Clause 2.95 before being surrounded by
concrete.
2. Concrete provided as a protection to pipes shall not be less than Grade
GEN 3, placed to the required depth in one operation.
3. Where pipes with flexible joints are used, concrete protection shall be
interrupted over its full cross-section at each pipe joint by a shaped
compressible filler, in accordance with Clause 2.19.
4. Where pipes are protected by a concrete slab placed above the pipe, this
shall span the pipe trench and extend a minimum of 300 mm both sides,
widening the trench above the pipe surround. There shall be a minimum of
150 mm of surround between the crown of the pipe and underside of the slab.
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5.3.5 (A)
Plastic pipe systems entering or exiting rigid restraint
situations should be protected by a compressible surround to
the pipe such as neoprene for a minimum distance of ½D or
for the available distance up to any water/thrust retaining
fittings.
5.3.6 (A)
At detachable flexible couplings and bolted gland type joints
the concrete protection shall be stopped 75 mm clear from any
part of the coupling or joint.
5.3.7 (A)
Details for any concrete embedment or surround for
thermosetting resin based pipes (e.g. GRP) shall be agreed
with the manufacturer.
5.3.8 (A)
Where two or more pipelines are laid in the same trench, the
joints shall coincide.
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Section 5 – Pipelines and Ancillary Works
5.4 PIPE SURROUND
(i) Further guidance is available in BS EN
1295-1.
(ii) The minimum side gaps for narrow
trenching techniques are stated for
compaction purposes.
1. Pipe surround material shall, where required, be placed and compacted
over the full width of the trench in layers not exceeding 150 mm before
compaction, to a finished thickness of between 100 mm to 300 mm above the
crown of the pipes.
2. Subsequent filling shall then be carried out, as specified in Clause 3.6.
3. Where trenching excavators or similar narrow trenching techniques are
employed for open dig laying of pipelines, the minimum gap between the pipe
barrel and side of the trench shall be 30 mm for pipe diameters of 280 mm or
less, and 50 mm for pipes greater than 280 mm diameter.
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5.4.4 (A)
Pipe surround shall be Type A10 granular material, or other
approved material.
5.5 PIPELAYING IN HEADINGS
(i) See also Clauses 3.1, 5.1 and 5.3.
1. Pipes to be laid in headings shall be supplied in lengths suitable for
handling, jointing and packing within the working space available.
2. Headings shall be driven from shaft to shaft, or in such other lengths as
may be described in the Contract, before any pipelaying is commenced.
3. After pipelaying, headings shall be packed solid with dry lean mix concrete
so as to fill all voids. Where manual packing is employed, each pipe shall be
surrounded before laying and jointing the next pipe.
4. Where grouting of headings is described in the Contract, grouting pipes
shall be left in the top of the heading projecting behind each head tree and
the whole grouted solid with grout Class G1. Grouting shall be carried out at
the end of each shift or after three settings have been packed, whichever is
the shorter interval.
5.6 THRUST BLOCKS
(i) Thrust blocks should be described in
the Contract.
(ii) Refer to CIRIA Report TN 128 for the
construction and design of thrust blocks.
1. Except where welded steel pipelines, welded polyethylene pipelines or self
anchoring joints are used, thrusts from bends and branches in pressure
pipelines shall be resisted by concrete thrust blocks cast in contact with
undisturbed ground.
2. Any additional excavation required to accommodate thrust blocks shall be
carried out after the bend or branch is in position and the thrust face shall be
trimmed back to remove all loose or weathered material immediately prior to
concreting.
3. Thrust blocks shall be allowed to develop adequate strength before any
internal pressure is applied to the pipeline.
4. Rapid hardening cement shall not be used in concrete for thrust blocks to
plastics pipes.
5. Plastics pipes shall be wrapped with a layer of plastic sheeting complying
with Clause 2.95 before being surrounded by concrete.
6. Where connections to existing mains incorporate the casting of thrust or
other support blocks, the temporary support shall be provided to pipework
until such time as the concrete has cured sufficiently to resist the effects of
forseeable pressure in the affected mains.
7. The depth of cover to concrete blocks shall not be less than 600 mm,
unless otherwise stated in the Contract.
8. Where a concrete surround to the pipe barrel is to be provided as
anchorage, a means shall be provided to transmit the load to the concrete,
e.g., via an integral stub flange or similar fitting to form a flange.
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5.6.9 (A)
A ground check is to be carried out to confirm that design
ground conditions are similar to those found on Site and if
different then the design is to be revised accordingly.
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5.6.10 (A)
Section 5 – Pipelines and Ancillary Works
For pressure mains where the gradient is steeper than 1 in 6,
a self-restraining joining system or anchor blocks should be
used. Where anchor blocks are proposed these should be
designed to suit the loading from the main and the local ground
conditions.
5.6.11 (A)
The Contractor shall not remove or interfere with any thrust
block, restraint or support on a live main, valve or fitting unless
adequate temporary restraints or supports have been
provided.
5.6.12 (A)
Where pipes, bends, tees, blank ends and other fittings have
been installed, repaired, renewed, altered or disturbed the
Contractor shall design and install an appropriate thrust block
taking into account the proximity of other services, the
operating pressure of the affected apparatus, the bearing
capacity of the surrounding ground and the period in which the
Employer requires the pipeline to be re-pressurised.
5.6.13 (A)
In repair scenarios or where fittings have to be removed and
replaced and the water supply restored as quickly as
practicable, adequate thrust restraint shall be provided that will
be effective within the timescale of the re-pressurisation. This
may take the form of:
a)
Mechanical couplings/flange adaptors with integrated restraint
systems (Type 2 in accordance with WIS 4-24-01 for PE or
WIS 4-21-02 for Iron Pipes).
b)
Thrust blocks or other adequate supports bearing against
undisturbed ground. All materials used shall be nonbiodegradable In the circumstances of (a) it must be taken into
account that this relies upon transferring the thrust from the
new fitting into axial tension (Type 1 in accordance with WIS
4-24-01 offers axial restrains) within the existing pipework
and this force is only restrained by the friction between that
pipe and the surrounding ground and the presence of an
unrestrained pipe joint near the connection may mean that the
length of existing pipe may be insufficient to absorb the
transferred thrust. Therefore additional measures such as (b)
above should also be considered dependent upon mains
pressure and the level of thrust generated by the fitting type.
5.6.14 (A)
All pipes, valves and fittings installed by the Contractor shall
be adequately supported and restrained to resist a working
pressure compatible with 1.5 times the pressure rating of that
pipe, valve or fitting allowing for surge, before the pipe, valve
or fitting is re-pressurised and backfilled.
5.6.15 (A)
Concrete support blocks shall be cast to hydrant tees, duckfoot
bends and sluice valves installed in plastic/MDPE/HDPE
pipelines in order to resist the operational torque imposed on
the fittings during operation. Support blocks shall be cast in
such a manner so as not to interfere with the operation or
maintenance of the apparatus.
5.6.16 (A)
Anchorage is not necessarily required at junctions or bends
where a fully integrated fusion weld PE pipe system is in place
(refer to the “Manual for PE Pipe Systems for Water Supply”
published by WRc). Anchorage is required for end Fire
Hydrant or Washout Hydrants even if temporary
5.7 PIPE JOINTING GENERALLY
(i) Any special requirements for filling the
joint annulus should be described in the
Contract.
CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
1. Pipe jointing surfaces and components shall be kept clean and free from
extraneous matter until the joints have been made or assembled. Care shall
be taken to ensure that there is no ingress of grout or other extraneous
material into the joint annulus after the joint has been made.
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(ii) The remaining flexibility is required for
any subsequent settlement or ground
movement.
Section 5 – Pipelines and Ancillary Works
2. Where pipes with flexible joints are required to be laid to curves, the
deflection at any joint as-laid shall not exceed three quarters of the maximum
deflection recommended by the manufacturer.
3. Where PE pipes are used, a fully welded system shall be used. Mechanical
or electrofusion joints shall not be used.
4. Joints shall be made in accordance with the manufacturer’s instructions.
5. The number of joints shall be minimised.
6. Where, as part of the work, the protective coating or lining to the existing
pipe or the new pipe is damaged, it shall be made good, as appropriate for
the protective coating or lining.
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5.7.3 (S)
Unless authorised by the Employer, all joints to PE pipe shall
be made using automated butt fusion or mechanical fittings
intended for PE of minimum Type 2 (In accordance with WIS
4-24-01) end load restraint rating. (See also 5.8). Mechanically
jointed flange adaptors of metallic construction should be
utilised to make flanged connection to PE pipe in preference to
using PE stub flanges. If PE stub flanges are used, then for any
flanged joints operating above 10bar or larger than DN 300,
reinforced flange gaskets shall be utilised
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5.7.7 (A)
Mechanically sealing under pressure tees (DN80mm branch
size or larger) shall not be used to make connections to PE
mains. Such joints shall only be made using Electrofusion
branch saddles installed by authorised teams meeting the
requirements of 5.8.4(A).
5.7.8 (A)
Connections to PE mains pipes that have been previously in
service (e.g. for repairs or branch connections) shall only be
made using mechanical couplings or flange adaptors.
Electrofusion shall NOT be utilised in these circumstances.
5.8 WELDED JOINTS IN POLYETHYLENE PIPES
(i) Any requirement for weld tests should
be described in the Contract.
1. Electrofusion and butt-fusion jointing shall be made in accordance with
WIS 4-32-08, using equipment specified in WIS 4-32-16.
2. Where PE barrier or co-extruded pipes are used, the jointing system
adopted shall be in accordance with the pipe manufacturer’s guidance and
all protective systems shall be made continuous across the joint.
3. A pipe section containing a completed weld shall achieve the same
strength characteristics as the parent pipe.
CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
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Section 5 – Pipelines and Ancillary Works
5.8.4 (A)
Jointing PE pipe with electrofusion couplers will only be
authorised by the Employer subject to: (i) evidence of
appropriately trained, equipped and accredited welders
undertaking that work, (ii) On PE pipe larger than DN 400mm
the welding personnel and the equipment being satisfactorily
audited by an external expert organisation approved by the
Employer (e.g. Exova) and approved before any joints are
made which would form part of the finished asset.(iii) All
jointing procedures being fully in accordance with the fittings
manufacturer’s instructions. Electrofusion couplers larger than
DN 630mm shall not be utilised to joint PE pipe without specific
written authorisation from the Employer.
5.8.5 (A)
Sample joints shall be made and witnessed then subsequently
tested in accordance with WIS 4-32-08 to ensure adequate
standards of toughness and ductility. Where these joint
samples are determined to have failed then corrections to
equipment and process shall be made to ensure satisfactory
joints and no such joints shall be included in the Works until
satisfactory test results have been obtained. Where a change
of welding equipment or personnel is made within the duration
of a scheme then further independent testing shall be required
to validate the performance.
5.8.6 (A)
For Schemes laying pipe in excess of DN315mm using
Electrofusion further site audits shall be undertaken on the
basis of one per 0.5km of pipe laid.
5.8.7 (A)
For schemes laying pipe in excess of DN450mm dia using butt
fusion jointing, the welding personnel and equipment shall be
initially audited as per 5.8.4 (A) above.
5.9 FLANGED JOINTS
(i) Any special requirements for the type
of flange gasket should be described in
the Contract (see also Clause 2.49).
1. Jointing compounds shall not be used when making flanged joints.
5.10 OGEE JOINTS
(i) Any required jointing material (mastic
or cement mortar) should be described in
the Contract
1. Ogee joints shall be so made that the required jointing material fills the joint
cavity. Any surplus jointing material extruded inside the barrel shall be
trimmed off and, where practicable, pointed on completion.
5.11 WELDED JOINTS IN STEEL PIPES
(i) For guidance on welding, reference
may be made to BS EN 1011-1, BS EN
1011-2, BS 2971, BS 4515-1 and BS
4515-2.
(ii) The types of welded joint should be
described in the Contract.
(iii) The frequency and type of testing
should be described in the Contract.
1. The process of welding carbon steel and stainless steel pipelines shall be
in accordance with BS 4515-1 and BS 4515-2, respectively.
2. The ends of pipes shall be cut and prepared, and be free from fins, planar
defects, tears and other surface defects, prior to welding. Cleaning to base
metal shall extend for at least 25 mm from the end of the pipe on both internal
and external faces.
3. The alignment of abutting pipe ends shall be such as to minimise the
internal offset between surfaces.
4. Details of the proposed welding and welding repair procedures shall be
stated in the Contract. Prior to commencement of production, test welds using
these procedures shall be made under simulated Site conditions.
5. Welders shall be certified by TWI and welders shall only make welds for
which they hold a current certificate.
6. Joints shall be tested using non-destructive techniques, unless it is
necessary to use destructive testing to achieve adequate interpretation.
5.12 CEMENT MORTAR JOINTS
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1. In making yarn and mortar joints for pipes or fittings, the spigot shall be
entered into the socket of the last pipe laid until it bears on the back face of
the socket and it shall be centred in the socket. Two turns of tarred yarn shall
then be caulked into the back of the socket and Class M12 cement mortar
shall be pressed into the joint to fill the socket and shall be bevelled off at 45o
from the outside edge of the socket.
5.13 RUN LEAD JOINTS
1. Run lead joints shall be made by forcing home strands of white sterilised
jute piping yarn, to the back of the socket cavity leaving a space of 75 mm
(60 mm for pipes of 300 mm nominal bore and below) measured from the
socket face. The socket face shall then be encircled by a suitable clip or
gasket with a clay seal and the joint cavity filled with molten lead poured in
one running. After cooling, the lead shall be set up and neatly finished with
the face of the lead 2 mm back from the socket face. In the case of pipes over
750 mm diameter, the socket and spigot shall be heated before the joint is
run.
5.14 PROTECTION OF FERROUS PIPES, JOINTS AND FITTINGS
(i) Any limitation on the type of external
or internal protection required should be
described in the Contract.
1. Ferrous pipes, fittings and couplings shall be specified with factory-applied
corrosion protection systems appropriate for their conditions of installation.
Reference is made to Clause 2.36.
(ii) The type of external protection
required should be described in the
Contract.
2. Where additional external protection is required to joints and fittings, they
shall be cleaned and all loose rust removed before protection is applied.
External protection shall comprise:
(iii) For guidance on cathodic protection,
see BS 7361.
P1 - The application of a thin continuous coating of petroleum paste over the
whole area to be protected as a primer. Where bolt heads, nuts, flanges and
other projections arise, a profiling mastic shall be used to give a smooth
external profile. The joint or fitting shall be wrapped with a protective tape.
The minimum application shall be a spiral wrap using 55% overlap. The tape
shall extend along 150 mm of the barrel of the pipe on each side of the joint
or fitting.
(iv) Any requirements for the design of
the cathodic protection should be
described in the Contract.
or
P2 - The application of a continuous coating of bitumen primer over the whole
area to be protected. Where bolt heads, nuts, flanges and other projections
arise, a profiling mastic shall be used to give a smooth external profile. The
joint or fitting shall be wrapped with a self-adhesive, cold-applied, rubber
bitumen tape with a PVC backing. The minimum application shall be a spiral
wrap using 55% overlap. The tape shall extend along 150 mm of the barrel
of the pipe on each side of the joint or fitting.
or
P3 - The application of heat shrink sleeves.
3. Completion of internal and external protection of steel pipes shall be
provided where pipes have a bituminous, epoxy or any other type of
protective coating in which a gap has been left for the joint to be
made. The joint and any damage to the protective coating shall be made
good, see Clause 5.7.6.
4. Cathodic protection of pipes, joints and fittings shall comprise either
impressed current or sacrificial anode.
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5.14.5 (A)
Where un-coated or inadequately protected joints and fittings
are supplied then they shall be cleaned and all loose rust
removed before protection is applied. Protection shall
comprise of one of the following:
a)
CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
Pipe barrel and fittings bodies shall be protected with a
continuous coating of bituminous paint and where ground
conditions require, and additional barrier layer of
bituminous plastic tape, heat shrink sleeving or site
applied polyethylene sleeving made secure to the joint
protection.
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b)
Section 5 – Pipelines and Ancillary Works
Where pipe and fittings are to be buried then additional
protection to joints couplings and fittings shall be provided
as P1, P2 or P3.
5.14.6 (A)
For Ductile Iron pipe and fittings refer to Heading 2.36.
5.14.7 (A)
Steel pipe and fittings shall be protected with appropriate
barrier systems inside and out. Cathodic protection may also
be specified. After jointing, the corrosion protection system
shall be reinstated over the area of the joint and any damage
to a similar standard to the factory applied system.
5.14.8 (A)
Flanged joints and mild steel fittings shall be cleaned and all
loose rust and deleterious material shall be removed and they
shall be externally protected as follows:
P2 Sheraplex coated bolts and nuts will be used on all flanged
joints except for specialist couplings where the manufacturer’s
bolts and nuts will be used.
P5 All ductile iron pipes will be supplied with a factory applied
protective epoxy coating to provide corrosion protection. Any
damage to the protective coating must be repaired in
accordance with the manufacturer’s instructions prior to laying
of the pipe.
5.14.9 (A)
Pipework and fittings that are to be exposed to air are to be
protected externally after installation with black bitumen paint
to BS53416, film thickness 100 micron applied in two coats.
5.15 CUTTING PIPES
(i) Requirements for welded joints in steel
pipes are given in Clause 5.11.
(ii)
‘The
Control
of
Asbestos
Regulations’, 2006 the ‘Control of
Asbestos Regulations (Northern Ireland)’
2007, the ‘Approved Code of Practices’
L127 and L143 have been introduced to
enable a more risk-based approach to be
taken for the control of asbestos.
(iii) Guidance Notes are available from
the HSE which detail the precautions to
be taken when dealing with asbestos
cement.
(iv) A regulatory position statement
‘Leaving Decommissioned Asbestos
Pipes in Excavation’ and guidance notes
are available from the Environment
Agency.
Yorkshire Water Services Ltd additional,
new or substitute clauses
CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
1. Pipes shall be cut by a method which provides a clean square profile,
without splitting or fracturing the pipe wall, and which causes minimum
damage to any protective coating. Where necessary, the cut ends of pipes
shall be formed to the tapers and chamfers suitable for the type of joint to be
used, and any protective coatings shall be made good and the ends sealed
in accordance with Clause 5.7.6.
2. Where ductile pipes are to be cut to form non-standard lengths, the
Contractor shall comply with the manufacturer's recommendations in respect
of ovality correction and tolerances to the cut spigot end.
3. Where concrete pipes are cut, any exposed reinforcement shall be sealed
with an epoxy resin mortar.
4. Pre-stressed concrete pipes shall not be cut on Site.
5. Appropriate safety precautions shall be taken when cutting asbestos
cement pipes.
5.15.6 (A)
Pipe cutting shall be carried out with an approved mechanical
pipe cutter and subject to a site specific risk assessment. The
use of abrasive wheel cutters for cutting into existing mains will
not be permitted for safety reasons.
5.15.7 (A)
The R&M Contractor should utilise the Employer’s Strategic
Equipment for the cutting of medium and large diameter pipes.
The Contractor may provide alternative pipe cutting
equipment.
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5.16 PRECAST CONCRETE MANHOLES
(i) The type of jointing material should be
described in the Contract.
1. Where steps, ladders and slabs are used in precast concrete chamber and
shaft sections, they shall be aligned correctly.
2. Joints shall be made so that the required jointing material fills the joint
cavity. Any surplus jointing material extruded inside the chamber or shaft shall
be trimmed off and joints shall be pointed on completion.
3. Where manholes are to have a concrete surround, the concrete shall not
be less than Grade UMB (GEN3) and the height of each concrete pour shall
not exceed 2 m. Each construction joint shall break joint with that of the
chamber or shaft sections by at least 150 mm.
4. Holes required in precast concrete chamber units to allow pipework to pass
through shall be made in-situ, and oversized by the minimum amount
required to ensure a watertight seal around the pipe by pre-drilling around
their perimeters. Any overbreak of holes shall be made good using a mortar
suitable for the pipe material.
5.17 BRICKWORK MANHOLES AND CHAMBERS
1. Manholes and chambers shall be constructed in English Bond using M12
sulphate-resisting mortar and Class B engineering bricks.
5.18 INVERTS AND BENCHING
(i) The benching material and surface
finish should be described in the
Contract.
(ii) The surface finishes referred to are
specified in Clauses 4.21 and 4.22.
Yorkshire Water Services Ltd additional,
new or substitute clauses
1. Where a wearing screed is required, it shall have a smooth, high-strength
concrete topping applied with a steel trowel before the concrete has set.
2. Inverts and benchings in manholes, chambers and the wet well shall have
a screeded, ridged finish.
5.18.2 (S)
Inverts and benchings in manholes, chambers and the wet well
shall have a smooth, high-strength concrete topping applied,
unless otherwise specified by the Employer.
5.19 PIPES AND JOINTS ADJACENT TO STRUCTURES
(i) Where a pipeline is to be constructed
in ground which is variable or unstable,
it may be appropriate for multiple rocker
pipes to be provided to accommodate
the anticipated differential settlement.
(ii) If flexible pipes are being used,
rocker pipes are not needed.
1. Except where the construction is by tunnelling, heading or pipe jacking, a
flexible joint shall be provided as close as is feasible to the outside face of
any structure into which the pipe is built, compatible with the subsequent
movement of the joint.
2. The length of the next pipe (rocker pipe) away from the structure shall be
as set out below:
Nominal Diameter (mm)
Effective Length (m)
150 to 600
0.6
Over 600 to 750
1.0
Over 750
1.25
3. A pipeline may, where practicable, be laid through a manhole and the
crown cut out to the half diameter, provided flexible joints are situated on each
side, no further than 600 mm from the inner face of the manhole wall, and
that adjacent pipes shall comply with Clause 5.19.2.
5.20 WATERTIGHTNESS OF MANHOLES AND CHAMBERS
1. Manholes and chambers shall be substantially watertight, with no
discernible flow of water penetrating the Works.
CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
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5.21 SETTING MANHOLE COVERS AND FRAMES
(i) If bedding of frames on resin mortar or
haunching in concrete (instead of mortar)
is required, this should be described in
the Contract.
1. Manhole frames shall be set to level, bedded and haunched externally over
the base and sides of the frame in mortar, in accordance with the
manufacturer’s instructions. The frame shall be seated on at least two
courses of Class B engineering bricks, on precast concrete masonry units or
on precast concrete cover frame seating rings to regulate the distance
between the top of the cover and the top rung to no greater than 675 mm. A
mortar fillet shall be provided where the corners to an opening in a slab are
chamfered and the brickwork is not flush with the edges of the opening.
2. Frames for manhole covers shall be bedded in a polyester resin mortar in
all situations where covers are sited in NRSWA Road Categories I, II or III
(i.e., all except residential cul-de-sacs). In all other situations, M12 mortar
shall be used.
3. Installation of surface box frames and covers shall comply with the
specification set out in BS 7903.
Yorkshire Water Services Ltd additional,
new or substitute clauses
5.21.1 (S)
Manhole, inspection chamber and surface box frames shall
be set to level, bedded and haunched externally up to the
edges of the frame base flange where there is sufficient
chamber wall beyond the base flange to allow this. Manhole
Frames shall be seated on at least two courses of Class B
engineering bricks at least 225mm (1 brick) wide, or on precast
concrete cover frame seating rings to regulate the distance
between the top of the cover and the top rung to no greater
than 675 mm. A mortar fillet shall be provided where the
corners to an opening in a slab are chamfered and the
brickwork is not flush with the edges of the opening.
5.21.2 (S)
All surface box, mahole cover and inspections chamber cover
frames located in carriageway shall be bedded in a polymeric
based bedding mortar compliant with HA 104/09 Pt6.
5.22 CONNECTIONS TO EXISTING SEWERS
(i) For information on repair couplings,
refer to BS EN 16397-1 & 2:2014.
1. Connections shall be made using standard pre-formed junctions where
possible. Saddle connections to existing sewers shall only be allowed when
the internal diameter of the major pipe is at least 150 mm greater than the
internal diameter of the branch pipe.
2. Pipe saddles for concrete or clay sewers shall be bedded in Class M12
mortar and a mortar fillet formed to give a cover of at least 50 mm to the base
of the saddle.
3. The ends of connections and pipes not required for immediate use shall be
closed with purpose-made stoppers, disks or joiners. The position of all
junctions shall be recorded by measurement from the manhole immediately
downstream and recorded with the as-laid information and submitted to the
Client for retention in the Client’s asset records.
5.23 SEWERS AND MANHOLES TO BE ABANDONED
(i) The material required for filling should
be described in the Contract.
(ii) Any requirement for clearing sewers
prior to filling should be described in the
Contract.
CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
1. Where sewers are to be abandoned and filled by grouting, the lowest point
of the abandoned length shall be suitably sealed, and the filling operation
shall commence from that point and continue progressively so as to fill all
voids completely.
2. The shafts of manholes on abandoned sewers shall be broken down to a
level 1 m below finished ground level and the remaining void filled as
described in the Contract.
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Yorkshire Water Services Ltd additional,
new or substitute clauses
Section 5 – Pipelines and Ancillary Works
5.23.1 (S)
Where sewers and pipelines are to be abandoned, the lowest
point of the abandoned length shall be suitably sealed, and the
pipe filled or plugged as agreed with the Employer. Filling of
the pipe shall commence from the lowest point of the
abandoned length and continue progressively to fill all voids
completely.
5.23.3 (A)
All abandoned sewers shall be inspected by CCTV prior to any
grouting to verify that all connections have been diverted to the
new sewer so as to avoid cutting off uncharted connections.
5.24 JUNCTIONS AND LATERALS ON SEWERS
1. Junctions and laterals shall be effectively sealed with an end cap, the
location of which shall be positively indicated.
2. End caps on junctions and laterals shall be secured by stakes and
concrete. Marker tape shall be laid between the location peg and end cap of
the lateral.
3. Records of depth and location of junctions at the sealed ends of laterals
shall be recorded and a copy of the record provided to the Client as work
proceeds.
5.25 MARKER AND INDICATOR POSTS
(i) Marker and indicator posts should be
sufficient to allow the location of the
water mains to be easily identified.
1. Marker and indicator posts shall be erected to show the location of valves
and other fittings, changes of direction and at field boundaries.
2. Permanent ground markers shall be constructed at locations shown. A
schedule of co-ordinates of the ground markers shall be supplied with the aslaid records and submitted to the Client for retention in the Client’s asset
records.
3. Marker posts shall be placed at field boundaries and in open country, and
shall be at intervals of not more than one kilometre.
4. Installation of indicator plates shall comply with the specification set out in
BS 7903.
Yorkshire Water Services Ltd additional,
new or substitute clauses
5.25.1 (S)
If specified by the Employer, marker and indicator posts shall be
erected to show the location of valves and other fittings, changes
of direction and at field boundaries.
Yorkshire Water Services Ltd additional,
new or substitute clauses
5.25.5 (A)
Indicator posts shall be embedded at least 450mm into the
ground, and blend in with surrounding features.
5.25.6 (A)
Detectable protective mesh tape shall be installed above water
pipelines and sewage pumping mains, ducts and cables
generally it shall be laid between approximately 300mm above
the pipe after partial backfilling and compaction is complete at
a depth of at least 650mm plus or minus 50mm below finished
ground level. The protective mesh shall be laid in the pipe
trench after partial backfilling and compaction is complete. The
tracer wire shall be continuous along the length of the main
and shall be connected onto a flange bolt on all valves on the
mains.
5.25.7 (A)
Where detectable protective mesh is exposed during the
course of any works in and around a pipe then such mesh shall
be reinstated to ensure continuity.
CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
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5.26 TOLERANCES FOR PIPELINES
(i) Any requirements for more stringent
tolerances should be described in the
Contract.
1. The line and level of any pipeline shall not deviate from that described in
the Contract by more than 20 mm and any combination of such deviations
shall not create a reverse gradient.
(ii) Where a pipeline is to be constructed
in ground which is variable or unstable, it
may be appropriate for a larger tolerance
for line and level to be described in the
Contract.
5.27 CABLE DUCTS
(i) Clauses 2.34 and 2.91 cover materials
for drawcords and cable ducting,
respectively.
1. The requirements of WIMES 3.02 shall be followed.
2. Cable ducts shall be laid with a 75 mm bed and surround of sand.
3. All ducts terminating in buildings shall extend 150 mm above slab level.
5.27.1 (S)
The requirements of Yorkshire Water Engineering
Specification Section 05 and associated WIMES 3.02 shall be
followed.
5.28 INSTALLATION OF VALVES
1. During installation, valves shall be kept in the closed position.
2. Extension spindles shall be accurately installed to hold the spindle in
alignment without binding. All valves shall be set so that the normal position
of the operating spindles is perpendicular to the line of the main.
3. After installation, any damage to corrosion protection coatings shall be
made good, in-line with Clause 5.14. Valves shall be tested to their full extent
to ensure their correct operation.
4. To avoid the necessity for man entry into any chamber for valve
opening/closing, an extension spindle shall be used.
5. Air valves shall be installed in drained chambers, where practical, and
where this is not, they shall be installed either with their air vent(s) at a level
higher than that to which water could rise or in sealed chambers.
6. Air valves shall be installed with an isolating valve between the
branch/tapping off the main and themselves, to facilitate their maintenance
without interruption to the mains supply.
7. Installation of fire hydrants shall comply with the specification set out in
BS 9990.
Yorkshire Water Services Ltd additional,
new or substitute clauses
CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
5.28.8 (A)
Air valves on distribution systems are a potential point for
contamination to enter a main and the following requirements
must be adhered to
a)
Air valves shall be carefully sited to avoid areas of poor ground
drainage and potential contamination risks. Pipework
design/gradients shall be altered if necessary to accommodate
this In private land they shall be located within 1m of the field
boundary. Where it is essential to locate an air valve remote
from the boundary the chamber structure shall be extended
above the level of the surrounding ground.
b)
Air valves shall be installed in drained chambers where
practicable and where this is impractical they shall be installed
with their air vent(s) at a level higher than that to which water
could rise. This may mean the construction of above ground
chambers with sufficient clear opening and internal space for
access to repair and maintain the air valve and isolating valve.
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Air valves shall be installed with an isolating valve between the
branch/tapping off the main and themselves to facilitate their
maintenance without interruption to the mains supply
c)
5.29 WASHOUTS
(i) For provisions relating to pollution of
watercourses, see Clause 1.15.
1. The washout layout shall ensure the safe disposal of the contents
discharged and shall not pollute any ditch, watercourse, highway drain or
surface water sewer.
2. To avoid the necessity for man entry into any chamber for operation, an
extension spindle shall be used.
3. Installation of underground washouts shall comply with the specification
set out in BS 7903.
5.30 ALTERNATIVE PIPE INSTALLATION TECHNIQUES
(i) ‘Horizontal Directional Drilling Good
Practices Guidelines (3rd Edition)’ is
available from the North American
Society for Trenchless Technology
(NASTT) (There is no guidance available
in the UK).
(ii) Other drilling/moling techniques are
available.
Yorkshire Water Services Ltd additional,
new or substitute clauses
1. Pipe splitting (mains bursting) shall be carried out in accordance with
‘Damage Control Procedures for Pipeline Construction Involving Pipe
Splitting’ issued jointly by British Gas (currently Transco) and UKWIR.
2. Directional drilling shall be undertaken in one continuous operation.
3. The drill/mole shall be fitted with a signal generator to assist in locating the
end and the route of the drill
5.30.4 (A)
Where service pipes are to be installed ‘open cut’, narrow
trenching, utilising vacuum excavation techniques shall be
utilised.
5.30.5 (A)
Where excavation is required and the existing pipe work
permits, Hydrant Mini Line Stop (Hydrant Wizard) shall be
used to replace or renew underground type two fire hydrants
and washouts.
5.30.6 (A)
Stop Tap Adaptors (STA) shall be the preferred method to
install domestic water meter within external stop tap chambers
where patterns of stop tap bodies can be matched. The STA
shall also be utilised for the replacement of broken stop taps
and for pressure and flow works.
5.30.7 (A)
Line stopping and associated temporary pipework shall be
utilised as instructed by the Employer.
5.30.8 (A)
PE100 polyethylene pipe SDR17 shall be used for pipebursting. For welded pipe the external bead weld shall be
removed prior to installation.
5.30.9 (A)
Unless specified for exceptional circumstances sleeve pipe
will not be used.
5.30.10 (A)
Any scoring in excess of 10% of the wall thickness will involve
removal of the pipeline. This will be determined by examination
of the pipeline carried out at excavations made for ferrule
connections or fittings. In the absence of such excavations the
Contractor shall agree the extent of the unacceptable pipe with
the Employer’s Representative and arrange for its removal
and subsequent replacement at the Contractor’s own cost.
5.30.11 (A)
Existing service connections will be renewed via a ferrule,
installed using fusion methods and short length of pipe where
required, connected to the existing pipework. No automatic
renewal of the communication pipe between the ferrule and
the stop-tap box will take place unless the condition of the pipe
warrants such replacement. Such a situation will arise where
the communication pipe is lead and there is a history of bursts
or leakage.
5.30.12 (A)
CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
The Contractor will slowly charge the renewed section of main
with water. When fully charged the joints shall be checked at
full static pressure to ensure that no visible leakage is present.
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Any visible leakage shall be corrected by the Contractor
immediately. The Contractor shall ensure that customer
supplies have been properly restored and shall be responsible
for all work necessary to restore these supplies. Should the
main fail upon pressure testing in such a manner that could
have resulted in the ingress of water or material to the main
then the Contractor shall undertake the chlorination process
again until a satisfactory bacteriological sample is obtained.
5.30.13 (A)
All welding of PE pipe for pipe-bursting shall be undertaken
using a fully automated fusion box to the following
specification.
1) The unit must comply with WIS 4-32-16.
2) The control box should have data-logging facilities for 1000
welds
3) The control box is to be downloaded by a portable USB
memory stick and files are to be encrypted.
4) The downloaded files must be able to be viewed in standard
Windows operating format (Excel or similar) for ease of
storage and sharing
5) The control box must have a minimum IP rating of IP65
6) The control box must have a USB barcode facility to enable
auto recognition of all manufacturers’ fittings
7) Data entry should be entered using an alpha numeric
keypad
8) The control box should provide visual information on
Operator, Location and Job reference all on one screen.
9) The control box must be provided with both 4.0mm and
4.7mm lead end adaptors
10) The control box must be capable of welding fittings with
fusion times over 2000 seconds
5.30.15 (A)
Drilling of the pilot bore shall be carried out to achieve a final
tolerance of +/- 100mm on line or level.
5.30.16 (A)
In the event of an obstruction being encountered that requires
a major route correction the Employer’s Representative shall
be informed prior to corrective action being carried out. In
extreme cases corrective action may require withdrawal of the
drill string and recommencement of the bore on a different line
and/or level.
5.31 CONNECTIONS TO EXISTING WATER SUPPLY PRESSURE
PIPELINES
1. The dimensions of the existing pipe at the point of connection shall be
checked to ensure the compatibility of the proposed connection fittings.
Yorkshire Water Services Ltd additional,
new or substitute clauses
CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
5.31.2 (A)
The Contractor shall make such connections between new
mains and existing mains as may be required by the Contract
or work instruction or as may be directed by the Employer. No
final connection shall be made until the new main is
successfully pressure tested, swabbed and disinfected to the
satisfaction of the Employer.
5.31.3 (A)
Before any connection is started, the Contractor shall give the
consumers affected 24 hours notice if the interruption to the
water supply is expected to last between 30 minutes and 4
hours, and where the interruption is expected to last for more
than 4 hours,48 hours notice shall be given. The water supply
shall be turned off at the agreed time and the mains drained
by either the Employer's or Contractor's personnel depending
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on the extent of impact on the distribution network. The
connection shall be performed with the Contractor's
Representative on Site. All shut off times shall be recorded on
the Employer's systems
5.31.4 (A)
The Contractor shall comply with the Employer's WAND
assessment.
5.31.5 (A)
Before any pipe is cut, it shall be exposed and checked for size
and ovality. Pipe diameters shall be determined using a
circumference tape, callipers may be used to determine ovality
5.31.6 (A)
The Contractor should note that a completely dry "shut-off" may
not always be possible and as such should allow for dealing with
some water which may come from within a cut pipe.
5.31.7 (A)
The Contractor should so arrange his methods of working that
on cutting the existing main, the work proceeds without
interruption until the connection is made and ready to be charged
up. Where appropriate, fittings comprising the connection shall
be pre-assembled and lifted into place in a single unit in order to
reduce the time the mains are shut down. The Contractor shall
provide and fix all necessary temporary support and strutting in
order to support the pipe assembly until concrete stools or thrust
blocks achieve maturity. Such support shall allow for the
possibility of leakage passing from the live main to the new
branch after making the connection.
5.31.8 (A)
On completion, the 'live' main will be isolated from the new
branch pipework. Under no circumstances is the Contractor to
make the system live unless authorised to in writing by the
Employer.
5.31.9 (A)
The work shall be staged so that initially, the minimum amount of
pipework has to be laid on the line of existing mains, in order to
restore the water supply as soon as is practicable. The remaining
pipework on the new main can then be laid at the Contractor’s
convenience.
5.31.10 (A)
Branch connections to existing mains shall be made using nondisruptive under-pressure equipment.
5.31.11 (A)
Where the Contractor is required to isolate and/or recommission sections of the water distribution system
operation of valves must be in strict accordance with the
Employer’s risk assessment, contained in a WAND. In
circumstances where the Contractor is unable to comply with
the risk assessment he must inform the Employer and receive
advice before proceeding.
5.31.12 (A)
Valve intervention impacts shall be created on the Employer’s
IT system by either the Employer or Contractor. The
Contractor shall update the Intervention Impact dates and
times.
5.31.13(A)
In order to ascertain whether a potable water burst is located
on the supply or communication pipe the Contractor should
first attempt to consult with the Customer before operation of
a boundary control valve.
5.31.14 (A)
Where a hydrant/washout is found to be leaking the contractor
will shut down this apparatus, or cap the outlet where possible,
and record this action on the appropriate documentation.
5.31.15 (A) The first choice for the connection of new mains to existing mains
should be in such a manner as to not interrupt the supply to
customers. Such methods include the use of under-pressure
tees and line stopping equipment.
5.31.16 (A) New Communication Pipes shall be laid along a line
perpendicular to the property boundary.
CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
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5.31.17 (A)
Section 5 – Pipelines and Ancillary Works
Before reconnecting a new communication pipe to a new or
existing ferrule, and if so directed by the pipe shall be
disconnected from the stop-tap, and cleaned by using a sanisnake, swab or other approved method from stop-tap to
ferrule.
5.31.18 (A)
Ferrules, shall only be installed after the main has been
charged, pressure tested and a satisfactory bacteriological
sample has been obtained. The Contractor must provide his
own pressure ferrule insertion machines compatible with the
type of ferrules to be installed. Electrofusion or butt-fusion self
tapping ferrules shall be provided for use on polyethylene
mains and should be installed in accordance with the
manufacturer’s instructions. The distance between ferrules in
a length of main shall be a minimum of 300mm or the
diameter of the pipe whichever is greatest on most mains
materials and where practicable 500mm on u-PVC pipe
material. New ferrules shall not be installed within 300mm of
an existing ferrule.
5.31.19 (A)
Connections to existing services which are copper shall be
made with either capillary or compression fittings.
5.31.20 (A)
Where a connection is required between either lead or lead
alloy and copper pipe this will be made with either a corrosion
resistant union wiped on to the lead or lead alloy pipe, or a
mechanical compression fitting, whichever gives the more
robust connection. In the case of wiped lead unions, not less
than 35mm of the pipe to which this is to be connected shall
be included within this joint.
5.31.21 (A)
The use of plastic ’push-fit’ type connections, including those
suitable for lead, copper, iron and other metals should be used
wherever the use of a ‘push-fit’ type connection can be utilised
in accordance with the manufacturer’s instructions and these
should take precedence over other connection options.
5.32 TEMPORARY WATER SUPPLY MAINS
(i)
The
arrangements
for
the
maintenance and removal of temporary
water supply mains should be detailed in
the Contract.
(ii) Where temporary water supplies are
required to cross highways and roads,
prior approval may be required from the
relevant
Highway
Authority.
Arrangements for the protection of these
temporary mains should be detailed in
the Contract.
Yorkshire Water Services Ltd additional,
new or substitute clauses
CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
1. The sizes, materials and locations of all temporary mains shall be agreed
with the Client, prior to commencement. All temporary mains shall be suitable
for the working pressure in the area.
2. Temporary mains shall be set up, disinfected and sampled, as specified by
the Client. The relevant connections shall be made and supply restored within
a period agreed with the Client.
3. The Contractor shall ensure that all temporary hoses and temporary mains
are kept free from ice and are fully operational during cold weather.
5.32.4 (A)
The Contractor shall provide and erect as required temporary
by-pass pipework of a type and condition suitable for the
conveyance of potable water, necessary to provide the
continuity of supply to customers affected by the Works. In all
circumstances the Contractor shall assess the need for bypass pipework and include such requirements in his scheme
proposal.
5.32.5 (A)
Non-return double check valves shall be provided on all
temporary pipework connections on to existing mains to
prevent back siphonage.
5.32.6 (A)
Any mains by-pass arrangements shall be designed to
withstand a maximum pressure of either 10 or 15 bar as
demanded by the circumstances and so that the minimum
numbers of fittings require dismantling and re-assembling as
work progresses. Each length of by-pass shall be connected
to the existing distribution system by means of such fittings as
are required by the Contractor and where approved by the
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Employer to enable satisfactory swabbing, flushing and
chlorination of the by-pass pipework and its isolation from live
mains. The connection and disconnection of by-pass pipework
to existing mains shall be undertaken, wherever possible, in
such a manner as not to interrupt customer’s supplies.
5.32.8 (A)
Each time the by-pass is disconnected and moved to the next
section of main to be worked on, it shall be sterilised in
accordance with Clause 7.12 .2 however, if the by-pass
pipework is suspected of being contaminated during its
transfer, the full procedure detailed in Clause 7.12.1 must be
adhered to.
5.32.9 (A)
All by-passes must be restrained as necessary and
adequately signed and lit for the protection of pedestrians and
road users.
5.32.10 (A)
The by-pass pipe may be required to be laid below the surface
of the road at points of public access. Where such road
crossings are heavily trafficked or at points where the
motorist’s vision is restricted, the by-pass shall be buried over
the full width of the access. Adequate signs and lamps will be
provided to warn motorists and pedestrians of the hazard.
5.32.11 (A)
Where the Employer directs that a temporary access be
constructed over the by-pass pipework, any such access point
shall be constructed to be capable of carrying the weight of a
domestic vehicle without causing damage to the vehicle or
pipe. The construction may be by use of pre-formed ramps or
suitably formed granular fill material or other means, subject to
the approval of the Employer.
5.32.12 (A)
Where appropriate the Contractor may utilise layflat potable
water hose for use as by-pass pipework, such as ‘Snap-tite
Tuff-light 122’ or similar approved to meet the following
requirements:
a) The hose shall be of diameters 2”, 3”, 4”, or 6” (or their
metric equivalent) and in 25 or 50 metre lengths. The hose
shall be approved by WRc to BS6920 up to an operational
temperature of 50 degrees centigrade and the hose assembly
shall meet the requirements of the Water Byelaws scheme –
Approved product. The hose shall be resistant to fuels and
oils, chemicals, abrasion, puncturing, ozone attack,
microbiological attack and weathering.
b) The end terminations of such hoses shall comprise one
male and female ‘Cam Action Quick Lock Coupling’ shall have
the following capabilities:
Nominal
Bore (inches)
Minimum Burst
Capability (bar)
Minimum Test
Pressure (bar)
Maximum
Working
Pressure (bar)
2
50
30
15
3
50
30
15
4
35
20
15
6
30
15
12
Each hose assembly shall be tested hydrostatically with water
to its maximum working pressure capability and a pressure
chart retained by the manufacturer/supplier.
5.33 WATER MAINS TO BE ABANDONED
(i) A regulatory position statement
‘Leaving Decommissioned Asbestos
Pipes in Excavations’ and guidance
CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
1. Where water mains or services are abandoned, they shall be physically
severed from the network. A closed gate valve shall not be used to achieve
disconnection.
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notes are available from the Environment
Agency.
(ii) The fill material should be detailed in
the Contract.
Section 5 – Pipelines and Ancillary Works
2. Where water mains are to be abandoned and filled by grouting, the lowest
point of the abandoned length shall be suitably sealed, and the filling
operation shall commence from that point and continue progressively so as
to fill all voids completely.
3. All abandoned mains shall be identified and recorded with the as-laid
information and submitted to the Client for retention in the Client’s asset
records.
4. Asbestos cement mains, where decommissioned, shall be recorded with
the as-laid information and submitted to the Client for retention in the Client’s
asset records. Where an asbestos main has been burst and asbestos shards
remain in the ground, this shall be recorded with the as-laid information and
submitted to the Client for retention in the Client’s asset records.
Yorkshire Water Services Ltd additional,
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5.33.2 (S)
Where water mains are to be abandoned the method of filling
or plugging shall be agreed with the Employer. The lowest
point of the abandoned length shall be suitably sealed, and if
required, the filling operation shall commence from that point
and continue progressively so as to fill all voids completely.
Yorkshire Water Services Ltd additional,
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5.34 (N)
STREET FURNITURE
5.34.1
All redundant street furniture shall be removed, voids
backfilled and re-instated.
5.34.2
Defective street furniture shall be made safe, on a temporary
basis, using secure plates or other suitable method e.g.
temporary tarmac.
Drop-in replacement lids shall be utilised where available
patterns matches the existing pattern.
Metal resins used as a permanent in-situ repair shall be mixed,
prepared and applied in accordance with the manufacturer’s
recommendations.
Yorkshire Water Services Ltd additional,
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5.35 (N)
GENERAL
PIPE
AND
FITTINGS
INSTALLATION TECHNIQUES
REPAIR
AND
5.35.1
Where excavation is required to stop taps, the Contractor shall
replace them with MSM boundary meter box assemblies with
full flow blanking plugs.
5.35.2
Leaking sluice valve glands shall be repaired utilising underpressure leak sealing packing material or other ‘live’ nondisruptive technique.
5.35.3
Options for, but not limited to, the repair to mains and services:
‘Snatching’ technique requiring live repairs subject to risk
assessment, network pressures, mechanical repair clamps
and fitting tools.
Fitting of repair clamps.
Removal of a piece or full pipe length and replacement with
dowel pipe and couplings.
Pipe freezing.
Pipe squeeze.
CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
5.35.4
Flow / line stopping and temporary by-pass systems for water
main repair and installation works shall be considered and
utilised particularly where isolation of the water distribution
network is complex, involves large numbers or sensitive
customers.
5.35.5
Where practical, the Contractor shall use a double spade valve
and bypass for connecting new and existing mains on
development sites. This will enable the new main (further
phase) to be connected, pressure tested and sterilised without
the need to depressurise the existing main to remove
temporary fittings.
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Section 5 – Pipelines and Ancillary Works
Yorkshire Water Services Ltd additional,
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Yorkshire Water Services Ltd additional,
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5.36 (N)
MAINTENANCE OF
SERVICE PIPES
ELECTRICAL
CONTINUITY
OF
5.36.1
The Contractor shall comply with the Employer’s “Maintaining
Earth Continuity of Metal Service Pipes’ Technical
Specification TS5 a copy of which is available through Health
and Safety Online via the Employer’s intranet
5.36.2
The Contractor shall install an approved electrical cross bond
(10 mm2 sleeved copper earthing cable) across all meter
installations where the meter is being installed within a metallic
service pipe. The Contractor shall also install an electrical
cross bond between the redundant metal service pipe and the
Customer’s internal pipework where a metallic service pipe
has been renewed up to, or a repair has been carried out at,
the point of entry to the property.
5.36.3
Should the Contractor suspect whilst working on the
Customer’s pipework that an electrical current (earth leakage)
is present in the pipe, he shall inform the Customer.
5.36.4
Notices have been prepared by the Employer to be issued to
customers. The notices shall be produced and delivered by the
Contractor to affected properties.
5.37 (N)
SERVICE PIPE BLOCKAGES
5.37.1
The Contractor shall take all reasonable precautions to
prevent the blockage of Service Pipes during the works. In the
event of a Service Pipe becoming blocked due to the activities
of the Contractor, arrangements shall be made to clear the
obstruction and any such work started will continue until the
supply is restored. The Contractor shall record the reason for
the blockage. If the Contractor considers that the blockage is
attributable to the condition of the Service Pipe the Employer
should be notified. The cost of blockages attributable to poor
workmanship or failure to take adequate precautions shall be
borne by the Contractor.
5.38 (N)
TEMPORARY SERVICE CONNECTIONS
5.38.1
Yorkshire Water is committed to undertaking work on the
network without interrupting supplies to its customers. Where
it is feasible all temporary service connections will be made
using stop-tap by-pass apparatus. This equipment allows
temporary service connections to be made to customers’ stoptaps without interrupting their supply.
5.38.2
Temporary supplies will generally be of 25mm or 32mm PE
pipe. Larger diameter supplies may be required for
commercial or industrial users and it may be necessary to lay
them beneath the surface of the footpath for part of their
length.
5.39 (N)
REQUIREMENTS FOR THE PROVISION OF FITTINGS ON
DISTRIBUTION MAINS (NOT TRUNK MAINS)
5.39.1
When any type of mains rehabilitation is being planned, the
scheme designer shall consider how to improve network resilience, to minimise
the impact of future planned and reactive operational activities. The scheme
designer shall consult with Local Engineers to verify that the location, and
distance between valves and washout hydrants being proposed provides
sufficient network connectivity.
CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
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Section 6 – Building Works
SECTION 6
BUILDING WORKS
The Notes for Guidance are not part of
the Specification.
(i) This Section is intended only for
small-scale masonry buildings and
basic steel framed and clad enclosures
on operational sites. Where design is
included in the Contract, all buildings
which are occasionally occupied and/or
heated should, as a minimum, comply
with the Building Regulations 2000.
6.1 BRICKWORK AND BLOCKWORK GENERALLY
(i) Any requirement for rendering of
manholes and chambers should be
described in the Contract.
(ii) The bond should be described in the
Contract.
(iii) The required class of mortar and
type of cement should be described in
the Contract (see Clause 2.82).
(iv) For guidance on the design of joints
and jointing in building construction, see
BS 6093.
1. Brickwork and blockwork shall comply with the relevant provisions of BS
EN 1996-2.
2. The moisture content of the bricks shall be adjusted so that excessive
suction is not exerted on the mortar.
3. Bricks in each course shall break joint correctly with the bricks
underneath. The courses shall be laid parallel with joints of uniform
thickness and shall be kept straight or regularly curved, as required.
Brickwork shall be gauged to rise 300 mm in four courses. Vertical joints
shall be in alignment, as required by the bond, and shall have an average
thickness of 10 mm. Bricks forming reveals and internal and external angles
shall be selected for squareness and built plumb. Bricks with single frogs
shall be laid frog upwards.
4. Brickwork and blockwork shall rise uniformly; corners and other advanced
work shall be raked back and not raised above the general level more than
1 m. No brickwork shall be carried up higher than 1.5 m in one day. No bats
or broken bricks shall be incorporated in the work, unless essential for bond.
Where cut blocks are required, all cutting shall be carried out with a
mechanical cutting disk.
5. Completed brickwork and blockwork shall be protected at all times from
scaffold splash, mortar droppings, grout leakage from suspended slabs and
the harmful effects of weather. Brickwork and blockwork shall be allowed to
set thoroughly hard before cutting or chasing is carried out.
6. Blocks used in fair faced blockwork shall have a smooth undamaged face
and be neatly pointed with flush joints.
Yorkshire Water Services Ltd additional,
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6.1.7 (A)
The Designer shall pay due regard to the requirements of
CDM, the Health and Safety at Work Act and the Manual
Handling Regulations e.g. when considering the use of
dense concrete blocks.
6.2 BRICKWORK AND BLOCKWORK, JOINTING AND POINTING
(i) The type of jointing and pointing
should be described in the Contract.
1. Bricks and blocks shall be laid in mortar, properly bedded and jointed,
and all joints filled with mortar at every course.
(ii) Any requirement for sample panels
and their approval should be described
in the Contract.
2. Where the surface of walling does not provide an adequate key, the joints
on faces of walls to be plastered shall be raked out 12 mm deep.
Yorkshire Water Services Ltd additional,
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6.2.3 (A)
CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
Jointing of new and existing brickwork shall take account of
relative movement between the new and existing structure.
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Section 6 – Building Works
6.3 CAVITY WALLS
(i) Where the filling or semi-filling of
cavities with insulating material is
required, it should be described in the
Contract.
1. Cavity walls shall have a minimium cavity width of 50 mm and a minimal
air gap of 25 mm between any cavity insulation and the outer skin. Cavity
walls shall be built with wall ties uniformly spaced, 450 mm apart vertically
and 750 mm apart horizontally, staggered, and laid to fall outwards.
Additional ties shall be used near the sides of all openings, one for each
third course of bricks. Care shall be taken to keep the ties within the cavity
free from mortar or mortar droppings, and any mortar or debris collecting at
the bottom of the cavity shall be cleaned out through temporary openings
left for this purpose in the bottom courses.
2. Weepholes shall be provided by leaving open perpendicular joints at
intervals not greater than 900 mm in the course immediately above the
cavity tray. Where the cavity tray does not extend the full length of the
exposed wall, i.e., at an opening and stop end, at least two weep holes, not
more than 450 mm apart, shall be provided.
6.4 DAMP-PROOF COURSES
1. Construction of damp-proof courses shall comply with the relevant
provisions of BS EN 1996-2, BS 6576, BS 8102 and BS 8215.
6.5 CORBELLING
1. Oversail corbelling shall not exceed 30 mm on each course.
6.6 BONDING TO CONCRETE
1. Where brickwork or blockwork is to be bonded to concrete, this shall be
achieved by means of metal ties evenly placed at three per square metre.
Brickwork and blockwork shall be brought up subsequent to the concrete.
6.7 UNDERPINNING
(i) Larger-scale underpinning should be
described in the Contract and may
require the services of a specialist
contractor.
1. Underpinning in brickwork shall be carried up to within one course of the
underside of the existing structure and allowed to set. The remaining course
shall be bedded in mortar and wedged tightly against the existing structure
with slate pieces.
6.8 CENTERING AND LAGGING
1. Centering and lagging used for the construction of brickwork and
blockwork shall remain in place for such time as is necessary for the
brickwork and blockwork to develop sufficient strength to prevent sagging
or cracking of joints.
6.9 BRICKLAYING AND BLOCKLAYING IN COLD WEATHER
1. Materials used in bricklaying and blocklaying shall be frost free and no
bricks or blocks shall be laid when the ambient temperature is below 3°C,
unless special precautions are taken. Any additives used in the mortar shall
not cause a variation in the colour of the joints. Completed work shall be
protected adequately during cold weather.
2. General working practices shall be in accordance with the Brick
Development Association publication ‘Bricklaying in Winter Conditions’.
CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
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Section 6 – Building Works
6.10 PREPARATION FOR PLASTERING
(i) The type of scrim material should be
described in the Contract.
(ii) If joints are to be cut or covered as
an alternative to scrim, this should be
described in the Contract.
1. Unless a bonding agent is used, concrete ceilings, ceiling beams,
columns and stanchions shall be dubbed out, as necessary, before
plastering is commenced and the mix used for dubbing shall be similar to
that used for first undercoating. The surface of in-situ concrete shall be
cleaned of dust, loose particles and other matter. Surfaces shall be wetted
immediately before plastering is commenced.
2. Angles between walls and ceilings, vertical angles and joints between
dissimilar solid backgrounds, shall be reinforced with 90 mm wide scrim set
in plaster and trowelled flat. All joints between plasterboards shall be
similarly treated.
3. Expanded metal angle beads shall be provided at all external corners.
6.11 FIXING OF PLASTERBOARD
1. Drylining shall comply with BS 8212. Plasterboard for ceilings shall be
fixed to the support at 150 mm centres with plasterboard nails, and fastened
so that the joints are staggered. Noggins or other fixing surface shall be
provided, as necessary, to ensure that edges of plasterboard are secured
adequately. Ends of sheets shall be butted tightly and edges left with a gap
not exceeding 5 mm.
2. Where sheeting has been cut, nails shall not be less than 18 mm from cut
edges. Nails shall be driven well home, with heads slightly below the
surface, but shall not break the paper.
6.12 PLASTERING
1. Plastering shall normally be applied in two coats, in accordance with the
manufacturer’s instructions, and batches shall be used as soon as possible
after water has been added. The total thickness of both coats shall be of the
order of, but shall not exceed, 13 mm.
2. Where three coat work is described in the Contract, the thickness shall
be of the order of, but shall not normally exceed, 18 mm.
3. The thickness of two coat work applied to concrete ceilings and soffits or
plasterboard shall not exceed 9 mm.
4. The thickness of finishing coats shall be of the order of 3 mm, except
where board finished plaster is used when the thickness shall be 5 mm and
comply with the relevant provisions of PD CEN/TR 15123, BS EN 13914-2
and BS 8481.
5. Expanded metal beads, or similar, shall be provided at all arrises.
6.13 PLASTERING IN COLD WEATHER
1. When the ambient temperature is 5°C or less, the portion of the Works to
be plastered shall be completely enclosed. The ambient temperature shall
be raised and maintained above 5°C until the completion of plastering and
hydration.
6.14 CONCRETE FLOOR FINISHES
(i) The type of finish from BS 8204-2 and
BS 8204-4 should be described in the
Contract.
1. Concrete floor finishes shall comply with the relevant provisions of BS
8204-2 and BS 8204-4.
2. Minimum thickness of sand/cement floor screeds shall be 35 mm when
laid directly on a prepared concrete slab or 75 mm when separated from the
slab by a membrane.
3. Structural concrete slabs shall be suitably treated to provide a full bond
prior to screeding, unless a membrane is to be used.
4. Screeds laid in wash down areas shall be laid to a minimum fall of 1 in
40.
CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
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Section 6 – Building Works
6.14.4 (S)
Screeds laid in wash down areas shall be laid to a minimal
fall of 1 in 40 or as described in the Contract or agreed with
the Employer.
6.15 FLOOR TILING
1. Floor tiling shall comply with the relevant provisions of BS 5385-3 and BS
5385-5 for rigid tiling and BS 8203 for flexible tiling.
6.16 TERRAZZO FLOOR FINISHES
1. Terrazzo floor finishes shall comply with the relevant provisions of BS
8204-4.
6.17 EXTERNAL RENDERING
1. External rendering shall comply with BS EN 13914-1 and shall be applied
to a total thickness of not less than 20 mm. The mix for both coats shall be
as for Class M2 mortar. The first coat shall be applied, levelled, scratched
and left to dry for not less than 3 days in warm weather and not less than 7
days in cold or wet weather. The suction of the surface of the first coat shall
be adjusted, as necessary, by wetting before applying the second coat
which shall be coloured as directed, levelled and lightly trowelled with a
wooden trowel.
6.18 WALL TILING
1. Wall tiling shall comply with the relevant provisions of BS 5385-1, BS
5385-2 and BS 5385-4.
6.19 CARPENTRY AND JOINERY
1. Wherever possible, cutting and shaping of all timber shall be completed
before preservative treatment is carried out. Where any cutting or shaping
has to be carried out after treatment, the cut or worked surfaces shall be
given two coats of the preservative. After treatment, timber shall be
thoroughly dried out before use.
2. The whole of the joinery shall be cut and framed together as soon as
possible after the commencement of the work. Workmanship shall comply
with the relevant provisions of BS 1186-2 and BS 6446. Except where work
is described in the Contract as being to finished sizes, 3 mm shall be allowed
for each wrot face. Frames, casings and other joinery fittings shall be
secured to hardwood fixing slips, built in for the purpose. Where hardwood
fixing slips have not been provided, receiving surfaces shall be plugged with
hardwood plugs or other suitable type plugs.
3. Manufactured units to be painted shall be primed at the place of
manufacture.
6.20 STRUCTURAL STEELWORK
(i) This clause is intended to apply to
basic structural steel framed buildings,
used to enclose process equipment.
(ii) Any particular design requirements
or architectural finishes should be
described in the Contract.
(iii) Where steelwork is to be galvanised,
it should be described in the Contract,
unless covered by Clause 6.20.3.
(iv) Other protective coatings, if
required, should be described in the
Contract.
CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
1. Built in joists used in masonry structures shall be cut to length by cold
sawing. The minimum bearing length on masonry shall be 100 mm, and
minimum crushing strength of supporting blockwork shall be 7 N/mm2 or a
padstone provided to spread the load.
2. Structural steelwork for steel framed buildings shall be designed, detailed,
fabricated and erected in accordance with BS EN 1993-1 and BS EN 10902.
3. All structural steelwork in buildings housing wet processes, or otherwise
prone to condensation, shall be galvanised to BS EN ISO 1461 with a coat
thickness of 85 µm.
4. Welders employed in the fabrication of steelwork shall be certified to BS
EN 287-1 for tests appropriate to the work to be undertaken.
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(v) Requirements for the testing of welds
should be described in the Contract.
Section 6 – Building Works
5. Steelwork to be embedded in concrete shall have any loose mill scale
and rust removed.
(vi) Structural steelwork should comply
with the ‘National Structural Steelwork
Specification for Building Construction’
published by the British Constructional
Steelwork Association.
6. As a minimum, all steelwork to be coated shall be blast cleaned to second
quality, then treated with two coats of quick drying primer, reference shall
be made to BS 7079. All surface treatment shall comply with the relevant
provisions of BS EN ISO 12944 and shall be completed, as far as
practicable, before steelwork is delivered to Site. Sampling and testing of all
surface treatment materials shall be in accordance with the Contract.
(vii) The Contract should state the
arrangements for sampling and testing
of all surface treatment materials.
7. All steelwork fastenings shall receive protective treatment to at least as
good a standard as the parts connected.
8. After tightening, all bolts shall have at least two threads projecting beyond
the nut or lock nut. Bolt shank length shall be such as to ensure at least one
thread shall remain clear between the nut and the shank.
9. When required, the following tests of butt welds shall be made;
(a) Ultrasonic examination to BS EN ISO 17640:2010;
(b) Penetration test to BS EN ISO 3452-1:2013; or
(c) Magnetic particle test to BS EN ISO 9934-1.
10. Erection tolerances for buildings containing an overhead gantry crane
should comply with the requirements of Appendix F in BS 466:1984.
Yorkshire Water Services Ltd additional,
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6.20.11 (A)
All surface damage or interruptions to structural steelwork
coatings shall be reinstated as per the specified renovation
methods in BS EN ISO 1461:2009. If a Zinc Rich primer is
used this shall comply with BS 4652.
6.20.12 (A)
Corrosion Protection
Where specified corrosion protection shall be provided by
either hot dipped galvanizing or protective coatings as
described below:
a)
Hot dipped galvanizing
Hot dip galvanizing shall be applied in accordance with
BSEN1461. Where galvanized coatings are damaged
repairs shall be undertaken using one of the methods given
in BSEN1461.
If the chosen method of repair uses a zinc rich primer the
primer shall comply with the requirements of BS4652.
Repairs to galvanized coatings shall not be made using
Galvafroid or materials that are applied from an aerosol can.
b)
Protective coatings.
Corrosion protection by protective coatings shall use the
material specification given in CIRIA Report 174 that is
appropriate to the service environment and required design
life.
Repairs to damaged coating specification shall be in
accordance with the requirements of the original
specification.
The requirements of this clause do not apply to general
painting and decorating of items other than structural steel.
See clause 2.88 for general painting and decorating
requirements
6.20.13 (A)
Delete all Clauses 1 to 9 and replace with;
Structural steel shall be fabricated and erected in accordance
with the “National Structural Steelwork Specification for
Building Construction” published by the British Construction
Steelwork Association (BCSA).
CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
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Section 6 – Building Works
6.21 ROOFS
1. Roof members shall be fabricated in accordance with BS EN 1995-1-1.
2. Flats and gutters shall be covered with BS EN 636-3G plywood or
tongued and grooved wrot boarding laid diagonally, firred to falls of not less
than 1 in 120 for lead and copper and 1 in 60 for bitumen felt.
6.22 TIMBER FLOORS
(i) Thickness of floor boarding should be
described in the Contract.
(ii) If chipboard is to be used instead of
floor boarding, this should be described
in the Contract.
1. Floor joists shall be either built into brickwork or blockwork, or held in
galvanised steel joist hangers, and shall be trimmed, as described in the
Contract. Bridging shall be spaced at every 1.8 m apart and shall be 50 mm
thick to the full depth of the joists, or 38 mm by 50 mm herringbone strutting.
2. Boarding shall be cramped up and nailed with cut flooring nails. Trimmed
openings shall have mitred borders 75 mm in width.
6.23 DOOR FRAMES
1. Door frames shall be fitted into prepared openings, drilled and plugged at
three points per jamb. Fixings shall be suitable for the proposed application
and be not more than 600 mm apart and not more than 150 mm from top or
bottom. The door frame shall be bedded in non-shrink or epoxy grout.
2. The joint between external door frames and adjacent walls shall be
continuously pointed with gun-applied butyl or other approved non-setting
mastic.
6.24 WINDOWS
(i) Security requirements for windows
and doors should be stated in the
Contract.
1. Window frames shall be securely fixed to openings, in accordance with
manufacturer’s instructions, and shall be continuously pointed with gunapplied butyl or other suitable non-setting mastic.
6.25 GLAZING
1. Glazing shall comply with the relevant provisions of BS 6262.
6.26 PAINTING
(i) BS EN 927-1 gives guidance on
exterior paint protection systems.
(ii) Refer to Clause 2.88 for paintwork on
buildings.
1. Painting of structural steelwork shall comply with the relevant provisions
of BS EN ISO 12944. Other painting shall comply with the relevant
provisions of BS 6150.
6.27 SLATING AND TILING
(i) The types and sizes of slate and tiles,
together with details of any laps,
battens, fixings, beddings, underfelt and
boarding, should be described in the
Contract.
1. Slating and tiling work shall comply with the relevant provisions of BS
5534.
6.28 LIGHTWEIGHT CONCRETE ROOF SCREEDS
1. Lightweight concrete roof screeds shall be laid to the necessary falls and
shall comply with the relevant provisions of BS 8217. Before any felt is laid,
a coat of bitumen primer shall be applied and allowed to dry.
6.29 ASPHALT ROOFING
(i) A written guarantee may be available
for asphalt work incorporating terms
currently applied by the Mastic Asphalt
Council and Employers' Federation.
CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
1. Mastic asphalt shall be laid in accordance with the relevant provisions of
BS 8218 on an underlay of sheathing felt, laid loose and with joints lapped
at least 50 mm. The roof shall be set out with properly formed high points,
water lines and mitred bays, where required.
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Section 6 – Building Works
6.30 BITUMEN FELT ROOFING
(i) The surface finish
described in the Contract.
should
be
1. Built-up bitumen felt roof coverings shall be laid in accordance with the
relevant provisions of BS 8217.
6.31 PLUMBING
(i) Where heating and hot water systems
are to be installed, reference should be
made to BS EN 12828, BS EN 12831
and BS EN 14336.
1. Plumbing for domestic water supply shall comply with the relevant
provisions of BS EN 806-2 and BS EN 806-4.
(ii) Reference should be made to the
Water
Supply
(Water
Fittings)
Regulations 1999, the Water Supply
(Water Fittings) Regulations (Northern
Ireland) 2009 or the Scottish Water
Byelaws 2004.
6.32 OPENINGS IN WALLS, FLOORS AND CEILINGS
1. Box outs and/or cut openings through walls, floors and ceilings for the
passage of pipes and cables shall be provided. Where described in the
Contract, tube sleeves cut off flush with the finished surface shall be
provided and fixed in position. All openings and ducts shall be sealed on
completion to prevent the passage of liquids, or toxic or explosive gases.
6.33 TOLERANCES FOR BUILDING WORKS
1. Tolerances for building works, except where otherwise described in the
Contract, shall not exceed the permissible deviations from levels and
dimensions given in BS 5606, where applicable, for the corresponding types
of work.
6.34 ELECTRICAL INSTALLATIONS
1. All electrical installations shall comply with the ‘Requirements for
Electrical Installations’, BS 7671 published by the Institution of Electrical
Engineers.
6.34.1 (S)
All electrical installations shall comply with Yorkshire Water's
Engineering Specification Section 05, associated WIMES
Specification Clauses and for Electrical System less than
1000V, ‘Requirements for Electrical Installations’, BS 7671
published by the Institution of Engineering Technology.
6.35 PROFILED STEEL CLADDING
(i) The colour of profiled steel may
require the approval of the Local
Planning Authority.
1. Profiled steel roof cladding shall be designed in accordance with BS EN
1993-1-3. In addition, the combination of purlin spacing and sheeting profile
shall be of adequate stiffness to prevent undue deflection (such as to cause
loss of balance) when walked on during erection and maintenance.
2. Sheets shall be supplied to Site, cut to the required length. Any incidental
Site cuts shall be sealed in accordance with the manufacturer’s instructions,
using matching materials.
3. Any cladding sheets with damage to the external protective coating shall
be rejected. Other damage shall be repaired as in Clause 6.35.2. Sheeting
shall be carefully stacked on Site with its dust wrap in place, until required.
4. Flashings and fillers shall be purpose-made to suit the profile of the
sheets being used.
Yorkshire Water Services Ltd additional,
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CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
6.35.5 (A)
Where planning permission is required the colour of profiled
steel cladding shall be to the approval of the Planning
Authority. In all other cases the colour shall be as specified
in the Contract.
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Section 6 – Building Works
6.36 PRECAST CONCRETE FLOORS
(i) These clauses are a guide for the use
of “beam and block” or pre-stressed
concrete planks up to 5 m span.
1. Units shall be delivered cut to the correct lengths and complete with any
service openings required. Any Site modifications shall be carefully cut in
accordance with manufacturer’s instructions, following specific permission
from the manufacturer in each case.
2. Any unit with handling damage to the bearing area shall be rejected.
3. Minimum bearing areas for precast units bearing on steelwork shall be as
laid down by the manufacturer. No negative tolerance shall be allowed on
these dimensions. Units bearing on masonry shall have a minimum bearing
length of 100 mm and the strength of the masonry shall be as specified by
the designer, but not less than 7 N/mm2.
4. In-situ structural topping shall be cast in the sequence laid down by the
Designer. Propping requirements shall be exactly followed and props left in
place until the specified strength is reached.
5. Bricks, blocks and other materials shall not be stored on the floor.
6. Units with excessive pre-camber resulting in differential levels between
planks exceeding 10 mm shall be rejected. Screeded floor finishes shall be
to the tolerances laid down in Clause 4.25.
6.37 COMPOSITE FLOORS
1. In-situ concrete floors utilising permanent steel soffit formwork as part of
a composite structural construction, shall not be used in buildings housing
wet processes or otherwise subject to condensation.
2. The exposed soffit of any such permanent formwork used shall be
protected to the same standard as the general structural steelwork.
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CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
6.38 (N)
IRONMONGERY
6.38.1
All ironmongery shall be fixed using screws having a similar
finish to the particular item concerned and any screws
damaged shall be renewed.
6.38.2
All wearing surfaces of lift-off hinges including rising butts,
shall be greased during fixing and the wearing surfaces of
other metal hinges shall be lubricated whilst laid flat using
light machine oil. Any other ironmongery requiring lubrication
for correct functioning shall be lubricated in accordance with
the manufacturer's recommendations.
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Section 7 – Testing and Disinfection
SECTION 7
TESTING AND DISINFECTION
The Notes for Guidance are not part of
the Specification.
(i) The Contract
requirements for:
should
describe
(a) temporary pipework, its connection to
existing mains and associated testing
apparatus;
(b)
disinfection,
chemical
and
bacteriological sampling, and the test
parameter values to be achieved; and
(c) samples and/or frequency of testing
of materials.
(ii) Refer to Guidance Note 2 of the
Water UK ‘Principles of Water Supply
Hygiene’ for guidance on the hygienic
transport and storage of new potable
water pipes.
(iii) Where water fittings and appliances
are to be used to convey water derived
from the public water supply, which
brings them under the scope of the
Water
Supply
(Water
Fittings)
Regulations 1999, the Water Supply
(Water Fittings) Regulations (Northern
Ireland) 2009 or Scottish Water Byelaws
2004, pressure testing should be
undertaken in accordance with these
regulations.
7.1 CLEANSING AND SWABBING OF PIPELINES
(i) The pipeline cleaning system should
be appropriate for the pipe material and
should be described in the Contract.
(ii) The Contract should describe the
type of swabs and the number of passes.
1. On completion of construction, and before any disinfection, internal
surfaces of pipelines shall be cleaned thoroughly.
2. On completion of the hydraulic test on water mains, a foam swab shall be
passed through the main a sufficient number of times to achieve clear wash
water.
3. All swabs shall be recovered and accounted for after mains cleaning.
Yorkshire Water Services Ltd additional,
new or substitute clauses
CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
7.1.4 (A)
The Contractor shall provide all necessary swabs, temporary
pipework and fittings.
7.1.5 (A)
Prior to pressure testing, the Contractor shall pass of a foam
swab of agreed texture through any newly laid main for final
cleaning.
7.1.6 (A)
In the event of a swab failing to emerge from the main, the
Contractor shall locate the swab and remove the swab and
any obstruction. The pipeline shall then be made good and
re-tested unless otherwise instructed by the Project Manager,
until a satisfactory result is obtained. All re-testing, clearing of
obstructions and making good the pipeline, shall be carried
out at the Contractor’s expense.
7.1.7 (A)
The Contractor shall be responsible for providing all
necessary swabs, temporary pipework and fittings. In general
swabs shall be soft absorbent hard-backed foam, medium
grade with a minimum diameter of 25mm greater than the
nominal internal diameter of the pipe, up to and including
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300mm pipework and 50mm greater for pipework of nominal
internal diameter greater than 300mm.
7.1.8 (A)
The Contractor shall provide and utilise as many swabs of the
appropriate grade as may be necessary for the wash water to
run clear. Swabs will be used once only, unless otherwise
approved by the Project Manager.
7.1.9 (A)
Potable water for swabbing will be made available to the
Contractor from YWS existing mains, free of charge for three
swab passes. Should further passes be necessary to clear
deleterious matter which may have accumulated during the
mains renewal or renovation work, a charge may be made for
the additional water used.
7.1.10 (A)
On no account should any valve, at any location in the main
or branches, be left shut, or partially shut, during swabbing.
At any such location the main or branch shall be blanked off
and the valve left with its gate in the fully open position.
7.1.11 (A)
Swabbing shall generally be carried out on lengths not greater
than 1km unless otherwise approved by the Project Manager.
7.2 PRECAUTIONS PRIOR TO TESTING PIPELINES
(i) See also Clauses 5.1 and 5.6.
1. Before testing any pipeline, it shall be anchored adequately and thrusts
from bends, branch outlets or from the pipeline ends shall be transmitted to
solid ground or to a suitable temporary anchorage.
2. Open ends shall be stopped with plugs, caps or blank flanges, properly
jointed.
3. Testing against closed valves shall not be permitted.
Yorkshire Water Services Ltd additional,
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7.2.4 (A)
The recharging process shall not commence until all work on
the main itself has been completed and personnel have been
removed from the trench or excavation.
7.3 TESTING METHOD PROGRAMME AND NOTIFICATION
1. The proposed programme and method of testing and swabbing shall be
stated in the Contract.
2. The Client shall be notified of the intention to test a section of pipeline
within the period specified in the Contract.
7.4 TESTING NON-PRESSURE PIPELINES
(i) The type of test (air, water, visual or
CCTV) should be described in the
Contract.
1. Non-pressure pipelines laid in open cut shall be tested after they are
jointed and before any concreting or backfilling is commenced, other than
such as may be necessary for structural stability whilst under test.
2. The pipelines shall be tested by means of an air or water test or by a visual
or closed-circuit television (CCTV) examination, in lengths determined by the
course of construction, in accordance with the programme.
3. A further test shall be carried out after the backfilling is complete.
Yorkshire Water Services Ltd additional,
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CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
7.4.2 (S)
Pipelines up to and including 750mm nominal diameter shall be
tested by means of an air or water test and pipes greater than
750mm nominal diameter by visual examination. Visual
examination may include the use of CCTV in lengths
determined by the course of construction, in accordance with
the programme.
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Section 7 – Testing and Disinfection
7.5 WATER TEST FOR NON-PRESSURE PIPELINES
(i) For provisions relating to pollution of
watercourses, see Clause 1.15.
1. The test pressure for non-pressure pipelines, up to and including 1000
mm nominal bore, shall be not less than 1.0 m head of water above the pipe
soffit or groundwater level, whichever is the higher at the highest point, and
not greater than 5 m head at the lowest point of the section. Steeply-graded
pipelines shall be tested in stages in cases where the maximum head, as
stated above, would be exceeded if the whole section were tested in one
length.
(ii) The allowable quantity of water
added is stipulated in Clause 13.3 of BS
EN 1610:2015
2. The pipeline shall be filled with water and a minimum period of 1 hour shall
be allowed for absorption, following which the original water level shall be
restored. Water shall then be added from a measuring vessel at intervals of
5 minutes over a 30-minute period and the quantity required to maintain the
original water level noted. The length of pipeline shall be accepted if the
quantity of water added in 30 minutes does not exceed 0.15 litres/m2 for
pipelines or 0.2 litres/m2 for pipelines and manholes tested together, where
m2 refers to the total area of the wetted internal surface.
3. Following a water test, pipelines and structures shall be emptied, as far
as is practicable.
Yorkshire Water Services Ltd additional,
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7.5.1 (S)
The method of testing non-pressure pipelines shall be agreed
with the Employer. Where water testing is required, the test
pressure for non-pressure pipelines, up to and including 1000
mm nominal bore, shall be not less than 1.0 m head of water
above the pipe soffit or groundwater level, whichever is the
higher at the highest point, and not greater than 5 m head at
the lowest point of the section. Steeply-graded pipelines shall
be tested in stages in cases where the maximum head, as
stated above, would be exceeded if the whole section were
tested in one length.
7.6 AIR TEST FOR NON-PRESSURE PIPELINES
(i) BS EN 1610 :2015 ‘Construction and
Testing of Drains and Sewers’, gives
advice on testing requirements.
1. Non-pressure pipelines to be air tested shall have air pumped in by
suitable means until a pressure of 100 mm head of water is indicated in a Utube connected to the system. The pipeline shall be accepted if the air
pressure remains above 75 mm head of water after a period of time “t” given
in the following Table without further pumping, following a period for
stabilisation.
Nominal Diameter
Testing time (minutes)
DN 100
5
DN 200
5
DN 300
7
DN 400
10
DN 600
14
DN 800
19
DN 1000
24
2. Failure to pass the test shall not preclude acceptance of the pipeline if a
successful water test can subsequently be carried out in accordance with
Clause 7.5.
7.7 CCTV INSPECTION OF PIPELINES
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(i) CCTV inspection should be
described in the Contract, if required.
Section 7 – Testing and Disinfection
1. CCTV inspections shall comply with the ‘Model Contract Document for
Sewer Condition Inspection’ 1994, published by The Foundation for Water
Research.
7.8 INFILTRATION
(i) The permissible infiltration is the
same as the permissible loss in the
water test in Clause 7.5.
1. Non-pressure pipelines (including tunnels and shafts) and manholes shall
be tested for infiltration after backfilling. All inlets to the system shall be
effectively closed, and any residual flow shall be deemed to be infiltration.
2. The pipeline, including manholes, shall be accepted as satisfactory if the
infiltration, including infiltration into manholes, in 30 minutes does not exceed
0.2 litres/m2, where m2 refers to the total internal surface area of the pipeline,
including manholes.
3. Notwithstanding the satisfactory completion of the above test, if there is any
discernible flow of water entering the pipeline at a point which can be located
either by visual or CCTV inspection, then measures as are necessary to stop
such infiltration shall be taken.
Yorkshire Water Services Ltd
additional, new or substitute clauses
7.8.4 (A)
The method of testing non-pressure pipelines and manholes for
infiltration shall be agreed with the Employer.
7.9 TESTING OF DUCTILE IRON, PVC, GRP AND STEEL PRESSURE
PIPELINES
(i) BS EN 805 gives the permissible
losses during the test.
1. The entire pipeline shall be pressure tested in accordance with
BS EN 805.
(ii) The Contract should specify either
a “water loss” or “pressure loss”
method of testing in accordance with
BS EN 805.
2. Gauges used for testing pressure pipelines shall either be of the
conventional circular type, not less than 200 mm diameter, calibrated in metres
head of water, or shall have a digital indicator capable of reading increments
of 0.1 m head. Before any gauge is used, it shall be checked independently
and a dated certificate of its accuracy shall be provided.
(iii) Details for Site pressure testing in
accordance with BS EN 805 are
provided in IGN 4-01-03 ‘Pressure
Testing of Pressure Pipes and
Fittings for Use by Public Water
Suppliers’.
(iv) Where a pipeline is to be tested in
sections, the Contract should identify
any constraints in length.
(v) The test pressures should be
described in the Contract.
(vi) Testing should be carried out with
the pipework isolated from the
existing adjacent pipework to prevent
the transmission of thrust.
3. Before testing, valves shall be checked and sealed, the sections of main
filled with water and the air released. After having been filled, pipelines shall be
left under normal operating pressure for 24 hours, so as to achieve conditions
as stable as possible for testing.
4. The pressure in the pipeline shall then be raised steadily until the specified
test pressure is reached in the lowest part of the section, and the pressure shall
be maintained at this level, by pumping, if necessary, for a period of one hour.
The pump shall then be disconnected, and no further water shall be permitted
to enter the pipeline for a further period of one hour. At the end of this period,
the original pressure shall be restored by pumping and the loss measured by
drawing off water from the pipeline until the pressure as at the end of the test
is again reached.
5. Where a new pipeline is to connect to an operational pipeline, the final
connection shall be inspected visually under normal operating pressure and
there shall be no visible leakage.
(vii) The testing of Polyethylene
Pressure Pipelines shall be carried
out in accordance with QMS
procedure 207.3.05 Pressure testing
of water mains and service pipes.
Yorkshire Water Services Ltd
additional, new or substitute clauses
7.9.6 (A)
The Contractor shall be responsible for providing all necessary
equipment for the testing of pressure pipelines, including
pipework, fittings and facilities to transport the water to the place
of testing.( IGN 4-01-03 Water Industry Standard)
7.9.7 (A)
Testing against closed valves or transmitting thrusts onto
existing or completed pipework shall not be permitted. Testing
shall be carried out with the pipework isolated from the
Employer’s existing mains.
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7.9.8 (A)
Conventional circular type pressure gauges shall have a
maximum reading no greater than two x test pressure.
7.9.9 (A)
The monitoring system shall be set up prior to pumping and will
include a data logger provided by the Contractor. This logger will
be set up at a hydrant location or a suitable tapping point by a
competent person to be nominated by the Contractor. A hard
copy printout from the logger will be held on file by the
Contractor as proof of the outcome of the test.
7.9.10 (A)
The permissible loss shall not exceed 2 litres per metre nominal
bore per kilometre length per metre head (calculated as the
average head applied to the section) per 24 hours.
7.9.11 (A)
In addition to any tests on separate sections, the whole pipeline
shall be tested upon completion to the same pressure and to the
same procedure as that outlined for the individual sections
where the pipeline length is less than 1000m. Testing is carried
out after swabbing but before disinfection of the main.
7.9.12 (A)
The Employers Representative shall be invited, in all cases, to
witness such tests, but notwithstanding this the Contractor shall
nominate to log the actions and results of such tests and to
forward the results in an appropriate format to the Project
Manager.
7.9.13 (A)
If a test fails on any length of pipeline, the Contractor shall be
responsible for locating and remedying the cause of failure
whatever its nature. Any defective pipes or couplings discovered
as a result of the test shall be replaced with sound ones at the
Contractor’s cost. The Contractor shall ensure that customer
supplies have been properly restored and shall be responsible
for all work necessary to restore these supplies. If the pressure
test fails then the process must be recommenced with swabbing
before pressure testing and then disinfection if required.
7.9.14 (A)
Where possible, mechanical joints should be left exposed to
allow visual inspection during testing.
7.9.15 (A)
On no account must operatives undertaking the testing be
allowed to leave the site prior to the main/service becoming fully
pressurised and it has been observed that all joints and pipes
are sound.
7.9.16 (N)
Acceptable alternative pressure tests:
i)
Live Installation
When a live installation technique is used for new mains
installations within an existing network by pipe-bursting, open
cut, directional drilling , slip-lining or close fit lining and
pre-chlorinated pipe is used and re-commissioned within the
day, when fully charged the joints shall be visually checked
at full static pressure to ensure that no visible leakage is
present. Note: Where multiple coils of pipe are used and not
re-commissioned within the day, an hydraulic pressure test is
required in accordance with Section 03.07 of the Engineering
Specification
ii)
Connections and Short lengths
For connections and short lengths of main up to 18 m and in
line with our chlorination procedures, when fully charged the
joints shall be visually checked at full static pressure to
ensure that no visible leakage is present.
iii)
Access points
Re-connection (piece-up) pipework at any access points for
pipe lining, swabbing, Ice pigging and Air scouring, when fully
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charged the joints shall be visually checked at full static
pressure to ensure that no visible leakage is present.
iv)
Services and temporary by-pass mains
For services and any temporary by-pass mains, when fully
charged the joints shall be visually checked at full static
pressure to ensure that no visible leakage is present.
Note: These alternative pressure tests only apply to
distribution mains i.e. mains supplied downstream of a
Distribution Management Area meter(s).
7.10 TESTING OF POLYETHYLENE PRESSURE PIPELINES
(i) Where a pipeline is to be tested in
sections, the Contract should identify
any constraints in length.
1. The testing of polyethylene pressure pipelines shall be carried out in
accordance with the procedures in IGN 4-01-03 ‘Pressure Testing of Pressure
Pipes and Fittings for Use by Public Water Suppliers’.
(ii) The test pressures should be
described in the Contract.
(iii) Testing should normally be
carried out with the pipework isolated
from the existing adjacent pipework
to prevent the transmission of thrust.
However, this might not be
appropriate where the test is
designed to test the tension capability
of welds and the transfer of thrust
through the pipeline.
Yorkshire Water Services Ltd
additional, new or substitute clauses
7.10.2 (A)
The testing of Polyethylene Pressure Pipelines shall be carried
out in accordance with QMS procedure 207.3.05 Pressure
testing of water mains and service pipes.
7.11 DISINFECTION OF WATER MAINS
(i) The Contract should describe the
sampling parameters.
(ii) Any specific requirements for
bringing water mains back on line
should be included in the Contract.
(iii) Timescales for the return of
sample results from bacteriological
and chemical sampling should be
described in the Contract.
(iv) Refer to Clause 1.16 for details
relating to water supply hygiene.
1. After satisfactory completion of testing and, if applicable, after swabbing,
pipelines intended for conveying potable water shall be disinfected in
accordance with ‘Principles of Water Supply Hygiene’ and the accompanying
Guidance Notes published by Water UK, or as specified in the Contract.
2. After disinfection and bacteriological and chemical sampling of completed
sections of water mains, no valves shall be turned or any other action taken
which might interfere with the main or existing network without the prior
agreement with the Water Undertaker.
3. On completion of the disinfection, the pipeline shall be left full of water under
operating pressure and with sufficient flow or changes of water so as to
maintain water quality.
4. Groundwater shall not be allowed to come into contact with the inside of
water mains after disinfection.
Yorkshire Water Services Ltd
additional, new or substitute clauses
7.11.5 (A)
Disinfection of completed sections of water mains shall be
carried out by the Contractor in accordance with the
Company’s procedures described in Level 2 Water
Quality manual in IMS 202.4.02
7.11.6 (A)
CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
Groundwater levels in all excavations or access chambers must
be maintained at least 200mm below invert level of the exposed
main, service or tapping point during installation. Pumps must
be available to prevent flooding while work is in progress.
Should ingress occur or be suspected of occurring the main
should be re-chlorinated and sampled as though it was a new
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Section 7 – Testing and Disinfection
main. Open ended mains must not be left unattended and
should be cap ended or pieced up.
7.11.7 (A)
All surfaces of pipes, services, fittings or material that are likely
to come into contact with potable water should be wetted with a
solution containing 1000mg/litre of free chlorine using sponge,
spray or immersion. Every effort should be made to wet all
internal surfaces of fittings such as valves or hydrants.
7.11.8 (A)
Once connected to the existing network the main should be
charged and flushed to expel air before being put into service.
7.11.9 (A)
The Contractor shall prepare pre-fabricated lengths or coils of
PE main for insertion, sufficiently in advance of mainlaying
operations to allow for chlorination and sampling. The main shall
be flushed, chlorinated and sampled as detailed in clause 7.12.
The pipe shall remain tightly sealed. When a pipe has been prechlorinated and sealed before use then it must be installed
within two weeks of the approved disinfection date. Where the
two week period has been exceeded the pipe must be rechlorinated.
7.12 CLEANSING OF STRUCTURES
1. On completion of construction, and before any disinfection, internal surfaces
of structures designed to retain or convey an aqueous liquid shall be cleaned
thoroughly in such a way as to remove all oil, grit and other deleterious matter.
7.13 TESTING OF CONCRETE ROOFS
(i) The Contract should describe
which of the two alternative tests is
required. Lagooning is the preferred
method but hosing may be used for
smaller structures.
1. Concrete roofs of structures which are to contain aqueous liquids shall be
watertight and shall, where practicable, be tested prior to the installation of any
waterproof membrane by lagooning with water to a minimum depth of 25 mm
for a period of 24 hours.
2. Where it is impracticable because of roof falls, or otherwise, to contain
25 mm depth of water, the roof shall be thoroughly wetted by continuous hosing
for a period of not less than 6 hours.
3. In either case, the roof shall be regarded as satisfactory if no leaks or damp
patches show in the soffit.
4. The roof covering shall be completed as soon as possible after satisfactory
testing.
7.14 TESTING OF CONCRETE STRUCTURES DESIGNED TO RETAIN AN
AQUEOUS LIQUID
1. After cleaning, and as far as practicable before any earth or other filling is
placed against the outside wall faces, concrete structures designed to retain
an aqueous liquid shall be filled with water at a uniform rate of not greater than
2 m in 24 hours. A period of up to 21 days shall be allowed for stabilisation,
after which the water level shall be recorded at 24-hour intervals, for a test
period of 7 days. During the test period, the total permissible drop, after
allowing for evaporation and rainfall, shall not exceed 1/500 of the average
water depth of the full tank or 10 mm, whichever is the lesser.
2. If the requirements for the 7-day test are not met then, after completion of
any remedial work, the structure shall be refilled and, if necessary, left for a
further stabilisation period after which the water level shall be recorded at 24hour intervals, for a test period of 7 days.
2. Not withstanding the satisfactory completion of the above test, any leakage
visible on the outside faces of the structure shall be stopped. Any caulking or
making good of cracks in the wall section shall, where practicable, be carried
out from the inside face.
3. The hydraulic test shall be carried out after successful completion of the roof
tests, before any disinfection work and before any sealing is undertaken.
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4. Adjacent internal chambers within a structure shall be tested sequentially.
Chambers adjacent to the chamber under test shall be empty during the test.
5. On satisfactory completion of the test, the structure shall be emptied, as far
as practicable, unless the water can be used as part of subsequent activities.
7.15 DISINFECTION OF STRUCTURES FOR POTABLE WATER
(i) This Clause will not apply if the
Client
directly
undertakes
disinfection.
(ii) For provisions relating to pollution
of watercourses, see Clause 1.15.
(iii) The Contract should describe the
sampling parameters.
(iv) Responsibility for taking samples
should be described in the Contract.
(v) Timescales for the return of
sample results from bacteriological
and chemical sampling should be
described in the Contract.
(vi) The period within which the Client
should make the sample test results
available to the Contractor should be
stated in the Contract.
1. Immediately before acceptance of any structure for potable water, the interior
shall be disinfected using water chlorinated to give a residual of not less than
20 mg of free chlorine per litre. Roofs and other surfaces above top water level
shall be sprayed with a solution containing 20 mg chlorine per litre. The
structure shall be emptied, flushed with mains water and then filled with water
having a chlorine residual of not more than 0.5 mg free chlorine per litre to
normal top water level.
2. After 24 hours, samples shall be taken for bacteriological and chemical
analysis. The structure shall be deemed to be disinfected if there are no
coliforms in the sample.
3. The Client shall arrange for samples to be taken which are representative of
the bulk of the water in the structure.
4. On completion of the disinfection, the structure shall be left full of potable
water, under operating pressure and with sufficient flow or changes of water so
as to maintain water quality.
(vii) The advance period notice for
taking of samples should be stated in
the Contract.
Yorkshire Water Services Ltd
additional, new or substitute
clauses
7.15.1 (S)
Immediately before acceptance of any structure for potable
water, the interior shall be disinfected using water chlorinated in
accordance with the Company’s procedures described in the
Level 2 Water Quality manual in IMS 202.4.03
7.15.5 (A)
All persons concerned with disinfection of structures for potable
water shall wear suitable protective clothing, provided solely for
use in the structures for water under preparation or conveyance
for public water supply, and on each occasion before entering
the structure shall wash their boots in 1000mg/L chlorine
solution. A tray containing such a solution shall be placed
immediately before the entry to the structure for this purpose.
The chlorine solution shall be changed daily or at such shorter
intervals that the Employer may direct.
7.16
(i) The Contract should describe any
constraints relating to the temporary
supply, including flow rate, pressure,
location of the supply and period of
notice required to make supplies
available.
WATER FOR TESTING, SWABBING AND DISINFECTION
1. Water for testing, swabbing and disinfection of potable water mains and
structures shall be taken from the existing potable water supply. Arrangements
shall be made with the Client for appropriate supply facilities.
(ii) Any particular requirements for
bridging
pipework
should
be
described in the Contract.
(iii) The arrangements for recording
and reporting volumes of water used
for testing, swabbing and disinfection
should be stated in the Contract.
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7.16.1 (S)
Potable water if required for cleansing, swabbing, disinfection
and testing purposes will be made available from the Employer’s
existing main. The Contractor will be responsible for providing
all the facilities to transport the water to the place of testing.
7.16.2 (A)
Potable water if required for testing purposes shall be provided
free of charge by the Employer.
7.16.3 (A)
Non return double check valves shall be provided on all
temporary pipework connections onto existing mains to prevent
back siphonage.
7.16.4 (A)
All valves controlling water from existing supply mains shall be
controlled in accordance with WAND.
7.17 DISPOSAL
DISINFECTION
(i) Flow rates should be specified in
the Contract for discharges to
sewers.
(ii) Consent to discharge to a
watercourse is issued by the
Environment Agency in England and
Wales,
and
the
Scottish
Environmental Protection Agency in
Scotland.
OF
WATER
FROM
CLEANSING,
TESTING
OR
1. The provisions for the removal and disposal of water used for disinfection,
swabbing or testing shall be stated in the Contract.
2. Discharges to sewers shall not take place without the consent of the
Sewerage Undertaker.
3. Water used in the cleansing, testing or disinfection of structures or pipelines
shall be rendered safe prior to discharge to the environment.
(iii) Water from disinfection is high in
chlorine and may have an adverse
effect on the environment and the
operation of sewage treatment works.
(iv) For provisions relating to pollution
of watercourses, see Clause 1.15.
Yorkshire Water Services Ltd
additional, new or substitute clauses
7.17.1 (S)
The Contractor shall be responsible for providing the facilities
for removal and disposal of water used for the testing, cleansing
or disinfection of structures and pipelines.
7.17.4 (A)
The Contractor shall be responsible for obtaining the relevant
consents to discharge, and for complying with the terms of the
consents.
7.18 TESTING OF NON-CONCRETE STRUCTURES FOR RETAINING
AQUEOUS LIQUIDS
(i) Tests for non-concrete roofs
should be described in the Contract.
(ii) The method for assessing the
change in water level should be
described in the Contract, together
with a reasonable interpretation of
“no discernible change”.
(iii) Rainfall and evaporation could be
assessed by using a test tank of a
similar size.
1. After cleaning, and before any external fill is placed against the structure, it
shall be filled to its overflow level at a rate approved by the manufacturer, or
detailed of the structure in the Contract. The water level shall then be recorded
for a period of 3 days. The tank shall be deemed to have passed the test if
there is no discernible change in water level after taking account of rainfall and
evaporation, and that there are no visible signs of leakage from the walls or
base of the structure.
2. This test shall only be carried out after a successful test of any roof structure.
3. Internal compartments shall be tested separately. Compartments adjacent
to the compartment under test shall be empty during the test.
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additional, new or substitute clauses
Section 7 – Testing and Disinfection
7.18.4 (A)
Prior to any hydraulic testing of the structure, all required nondestructive testing shall have been completed. Any faults found
shall be repaired and re-tested.
7.18.5 (A)
The water tightness test shall be carried out before any
disinfection work.
7.18.6 (A)
On satisfactory completion of the test, the structure shall be
emptied as far as practicable, unless the water can be used as
part of subsequent activities.
7.18.7 (A)
Immediately before acceptance of any non-concrete structure
for potable water, the interior shall be disinfected using water
chlorinated in accordance with the Company’s procedures
described in the Level 2 Water Quality manual in IMS 202.4.10.
7.19 (N)
TESTING AND DISINFECTION OF SERVICE CONNECTIONS
AND PIPES
7.19.1
Small fittings for Service Pipes such as ferrules, stop taps and
connectors should be immersed in a solution containing the
equivalent of 1000mg/l of chlorine, contained in a suitable
receptacle for a minimum of 2 minutes immediately prior to their
use in the Works. The solution shall only be used for up to 24
hours after mixing or until it becomes exhausted or
contaminated.
7.19.2
All Service Pipes shall be thoroughly flushed with potable mains
water prior to them being connected to the Customer's supply.
If there is any likelihood that the inside surface of the pipe has
become contaminated, then the pipe shall be discarded.
7.19.3
Following the installation or repair of a Service Pipe the
Contractor shall ensure that the whole length of the Service Pipe
is thoroughly flushed until all air or contamination has been
removed and the chlorine concentration has reached normal
background levels.
7.19.4
After installing the communication pipe and connection to pipes
laid by a Developer each pipe shall be tested to ascertain the
correct plot number / property served.
7.20 (N)
DISINFECTION, SAMPLING AND OPERATION OF WATER
MAINS
7.20.1
7.20.2
Disinfection procedures shall be conducted in compliance with
the recommendations outlined in ‘The Principles of Water Supply
Hygiene’. Disinfection is carried out after pressure testing of
mains. An up to date version of the Company’s Disinfection
Procedures are included in the Water Distribution Level 2 Water
Quality manual in IMS 202.4.02.
Customers should be advised to run water to waste for several
minutes following restoration of supplies in order to dissipate
any chlorine tastes or smells or possible discolouration.
7.20.3
The Contractor must ensure that no main or service can be
inadvertently turned into supply, either by his own personnel or
YWS staff, while the concentration of free chlorine in the water
is above normal acceptable levels.
7.20.4
The utmost care must be taken to prevent the contamination of
operational mains or services wherever the inside of the pipe is
exposed. However if dirty water (ground water) enters a main or
service, or if there is any suspicion that water from a foul drain
or sewer has entered the pipe, it must be swabbed, flushed and
disinfected as for a new main in accordance with the Project
Manager’s instructions and not returned to service until a
satisfactory bacteriological result has been obtained from YWS.
In such circumstances the Project Manager, Duty Manager and
Water Quality Scientist must all be informed immediately in
order that a decision can be made whether or not notices
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advising customers to boil water should be issued or to instigate
such other action as may be necessary. The Contractor will be
responsible for all expense incurred in such circumstances.
7.20.5
The Contractor shall supply the materials for disinfection.
The introduction of rapid release chlorine tablets which are
inherently safer to transport and handle, and have a ‘reasonable
shelf life’ before losing their strength, has rendered the use of
liquid sodium hypochlorite unnecessary when producing
disinfection solutions on site in small quantities.
7.20.6
Solutions should therefore be made up as required by dropping
tablets into a clean stainless steel bucket in accordance with the
manufacturer’s instructions. The solution should be gently
stirred and not used until the tablets have completely dissolved.
7.20.7
The following table is a guide to using either ‘Instachlor’ PR1000
rapid release chlorine tablets or sodium hypochlorite (chlorus)
which is solution containing 10% free chlorine at normal
strength.
7.20.8
7.20.9
Required concentration
Volume of
Number of litres of
of free chlorine in
chloros
water per
water (mg/litre)
to water
Instachlor tablet
1
1:100000
1000
10
1:10000
100
100
1:1000
10
1000
1:100
1
The Contractor is advised that products containing chlorine are
potentially hazardous and must be handled strictly in
accordance with a safe working procedure that satisfies the
requirements of the Health and Safety at Work Act.
Disinfection solution shall be prepared freshly on a daily basis.
Testing and neutralisation of water used for cleaning,
disinfection and testing
7.20.10
The Contractor shall be responsible for providing the facilities
for removal and disposal of water used for cleaning, disinfection
and testing of pipes.
7.20.11
Chlorinated water must not be allowed to enter a stream or
watercourse and shall not be discharged to the sewerage
system without the prior approval of the sewerage authority.
7.20.12
Where necessary de-chlorination of waste water shall be carried
out either by injection of Sodium Thiosulphate solution, using a
suitable mobile dosing unit or, by running the chlorinated water
over through sacks containing Sodium Thiosulphate crystals.
Disinfection procedure for modification to mains, installation of
fittings, repair of main, connection work
7.20.13
The disinfection of water mains, services, fittings, shall be
carried out by the Contractor in conjunction with all operations
requiring the de-pressurisation of any water mains, services or
fittings.
7.20.14
Groundwater levels in all excavations or access chambers must
be maintained at least 200mm below invert level of the exposed
main, service or tapping point during installation or repair.
Pumps must be available to prevent flooding while work is in
progress.
7.20.15
All surfaces of pipes, services, fittings or material that are likely
to come into contact with potable water shall be wetted with a
solution containing 1000mg/litre of free chlorine using sponge,
spray or immersion. Every effort shall be made to wet all internal
surfaces of fittings such as valves or hydrants.
7.20.16
On completion of the work the main must be thoroughly flushed
at the nearest downstream hydrant for a period of time which
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accounts for the size and length of the main, the flow and
pressure available within the system, also the risk of
discolouration and interruption to supply. The following table
suggests flushing times for mains in a normal urban situation:
Diameter of Main
Flushing time per 100m of
main*
3” (80mm)
4 minutes
4” (100mm)
7 minutes
6” (150mm)
15 minutes
*Measured from repair location to flushing hydrant
7.20.17
For the purposes of bacteriological testing the Contractor shall
take a sample from the nearest downstream hydrant.
7.20.18
The main may then be returned to supply.
7.20.19
The disinfection of all new water mains and temporary bypasses on first arrival shall be carried out by the Contractor in
conjunction with the swabbing and pressure testing of the main
unless otherwise directed by the Project Manager.
7.20.20
The Contractor shall provide all the equipment necessary for the
satisfactory completion of the work including pumps, meters,
chlorination unit, chlorine testing equipment (comparator and
tablets), hoses, standpipes and fittings.
It is required that the chlorination unit should have the facility to
combine measurement of flow with automatically adjusted
chemical injection rates in order to maintain an accurately
prescribed dosage of disinfection solution.
7.20.21
All pipework and fittings shall be stored and laid as hygienically
as practicable with reasonable measures taken to exclude
vermin, debris and dirty water. During pipe laying exposed pipe
ends shall be sealed with pipe stoppers (Cam stoppers or
similar) when left unattended for any length of time.
7.20.22
Following swabbing and pressure testing the following
disinfection procedure shall be applied.
Firstly the main shall be charged with potable water by way of
the dosing unit connected between two hydrants. The automatic
controls shall be adjusted such that the incoming water receives
a continuous dosage of 10% strength sodium hypochlorite
solution intended to achieve a free chlorine content of 20mg/litre
throughout the pipework. The concentration shall be confirmed
at each downstream hydrant using a comparator whilst the
water is still being discharged.
Where restricted access or road traffic considerations render
automatic dosing impracticable, the Contractor may choose to
use a ferrule as the injection point (situated as close to the live
valve as possible) in conjunction with a small portable pump.
The hypochlorite solution shall then be injected at a rate of 1.8
litres per hour whilst maintaining a flow of 150 litres per minute
of water through the main to produce the same free chlorine
content of 20mg/litre checked by comparator.
7.20.23
Chlorinated water shall be discharged for a sufficient period of
time to ensure that the main is fully charged with chlorinated
water of the required strength. The main shall then be isolated
by shutting hydrants and the main allowed to stand for a contact
period of 24 hours.
After the contact period has expired the chlorine residual of the
water should be checked to establish that it has not dropped
below 15mg/litre. In the event that chlorine levels are below
15mg/litre, indicating possible contamination of the main, the
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Contractor shall, at his own expense, carry out such additional
swabbing, re-chlorination and flushing as may be necessary to
obtain results that are to the satisfaction of the Project Manager.
7.20.24
After successful chlorination the Contractor shall flush the main
until the chlorine residual has reduced to normal background
levels. The main shall then be left to stand for a further period of
24 hours following which the Contractor shall take a sample. The
sample shall be taken by a nominated competent person and
the Project Manager’s site representative will be given the
opportunity to witness the taking of the sample.
The Contractor shall take the sample in a cool box to a
designated laboratory (or agreed drop off/pick up point) where it
will be examined for bacteriological, chemical and aesthetic
compliance.
7.20.25
The results will be available 18 to 24 hours after delivery of the
sample to the laboratory. The Contractor should initially phone
to receive information on the status of the sample. Faxed
confirmation will follow and this should be retained on file by the
Contractor and produced for inspection by the Project Manager.
Should any sample not be the standards required for potable
water, the Contractor shall undertake such additional swabbing,
chlorination and flushing as may be required to produce a
satisfactory result, all at his own expense.
Thereafter, the main shall be regarded as operational and the
Contractor shall not turn any valves or take any other action
which might interfere with the use of the main unless instructed
to do so by the Project Manager in order to carry out final
connections.
7.20.26
Newly laid mains shall not be connected directly to the existing
mains system (until cleared bacteriologically) except by way of
a standpipe fitted with a double check valve.
7.20.27
Mains up to 10m in length, connections, individually installed
fittings and previously sampled mains by-passes shall not be
subject to the mains disinfection process unless so directed by
the Project Manager but rather in accordance with Sub-clause
7.12 (12-17).
Disinfection of renovated mains
7.20.28
Access holes should be excavated to a depth of at least 200mm
below the main. Pumps must be available throughout the
lining/disinfection process to prevent any water in the excavation
from entering the open ends of the main.
Exposed ends of the pipe shall be sealed with stoppers when
the pipeline is unattended for any length of time.
7.20.29
The Contractor must ensure that all customers’ stop taps remain
closed wherever possible during the disinfection process.
7.20.30
All surfaces of pipes, fittings, stop taps, ferrules and other
equipment likely to come into contact with potable water should
be wetted by spraying with or immersed in a solution containing
1000mg/litre free chlorine prior to installation.
7.20.31
Special attention should be paid to CCTV equipment. Prior to
survey the camera head should be immersed in, or sprayed with
a solution containing 1000mg/litre free chlorine. During the
operation the CCTV cable shall be fed through a clean sponge
or similar which has been saturated with the same solution.
7.20.32
After satisfactory completion of lining and CCTV survey,
disinfection shall be carried out by spraying with a solution
containing 1000mg/litre of free chlorine. The spray shall be
drawn through the pipe ensuring that all surfaces of the pipe are
adequately wetted. The spray chlorinator shall be driven by a
machine and not hand pulled and will be capable of providing a
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printout (that will be kept for record purposes) showing that the
spray head functioned throughout the pull, the length of main
disinfected, the amount of solution used and the date and time
of disinfection.
It is important to ensure that contamination does not occur due
to back siphonage of water into the lined pipe as a result of
flooding of the works.
7.20.33
As soon as the spray chlorinator head exits the pipe the main
must be capped (quick fit stoppers such as Camstoppers are
useful for short term protection for the main) to protect it from
post disinfection contamination. It is particularly important to
ensure that contamination does not occur due to back
siphonage of water into the lined pipe as a result of flooding of
the works. Such protection of the main will remain in place up to
the point the main is ‘pieced up’ to the live main.
7.20.34
Charging up the main should ‘absorb’ the residual chlorine spray
within the main thereby avoiding the need for extensive flushing.
The chlorine residual should be checked using a comparator,
and the main flushed until a normal background level of chlorine
is achieved. At this point bacteriological, chemical and aesthetic
samples are taken for laboratory analysis.
7.20.35
Customer stop taps can then be opened and the main returned
to service, but as a further precaution, customers should be
advised to boil any water for drinking and food preparation for a
period of 48 hours after restoration of supplies. Should the
bacteriological test prove unsatisfactory an extension of the
boiling notice will be issued. Further cleaning/disinfection
measures may be required by the Project Manager or the YW
water quality scientist.
7.20.36
If the lined main supplies a dead end, precautions shall be taken
to ensure that there is no risk of stagnation during the first night
back in service. This is to be achieved by inducing a low flow of
water through the main such that the residence time is not more
than 1 hour for the first 24 hours in service. In practice this
equates to a flow of about 13 litres per minute in a 100mm pipe.
A dead end main is defined as the last 200m of main terminating
in a washout, hydrant or capped end.
Disinfection of service pipes
7.20.37
The Contractor shall act in full compliance with the general
clauses for disinfection which are 7.12 (1-4) and 7.12 (12-17).
7.20.38
Small fittings for service pipes such as ferrules, stop taps and
connectors should be immersed in a solution containing
1000mg/litre of free chlorine contained in a suitable receptacle
for a minimum of 1 minute individually prior to their use in the
works.
7.20.39
All service pipes, whether permanent or temporary, new or
repaired, shall be thoroughly flushed with potable mains water
prior to being connected to the customers’ supply.
If there is any likelihood that the inside surface of the pipe has
become contaminated then, depending upon the source of the
contamination, the pipe shall be discarded or disinfected.
Disinfection of the service pipe shall be achieved using a swab
soaked in a solution containing 1000mg/litre free chlorine driven
through the pipe using potable mains water pressure and then
flushed thoroughly prior to connection.
Yorkshire Water Services Ltd
additional, new or substitute clauses
7.21 (N)
SAMPLING FROM STANDPIPES, FILLING OF POTABLE
WATER CONTAINERS FROM STANDPIPES
7.21.1
Any standpipe for sampling or the filling of potable water
containers shall be specially constructed for the purpose with a
chrome or brass bib-cock or sample tap and should be kept clean
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7.21.2
specifically for this purpose and stored and transported in a clean
plastic bag. Standpipes for sampling should have drain taps to
ensure that no stagnant water is being sampled. Detailed
considerations on the sampling from Standpipes are described in
the Company’s Level 2 Water Quality manual in IMS 203.01.
If the hydrant chamber is full of water or debris, bale out or
remove to below the level of the frost plug in the hydrant bowl.
7.21.3
Open the hydrant valve carefully to wash out debris from the
hydrant bowl but do not flood the hydrant chamber
7.21.4
Bale out to at least 2.5cm from the top of the hydrant bowl and
place one Instachlor tablet into the bowl
7.21.5
Unwrap the standpipe from its plastic bag and screw into the
hydrant bowl with the bib-cock shut. Drain any water in the
standpipe from the tap, wait for 2 minutes then open the hydrant
valve slowly and then open the bib-cock unto chlorinated water
first discharges. Close the bib-cock and hydrant immediately.
7.21.5
Sterilise the bib-cock using a blowtorch and wait 5 minutes to
allow the heavily chlorinated water to disinfect the standpipe
7.21.6
Open the hydrant and bib-cock and allow the water to run to
waste for a couple of minutes, taking care that the first flush of
heavily chlorinated water does not splash clothing
7.21.7
After flushing test using a comparator to ensure that the level of
residual chlorine is no higher than normal for the distribution
zone
7.21.8
The standpipe is now ready for sampling or for public use. For
sampling adjust the bib-cock to a gentle stream and fill the
sample bottle or potable water containers.
7.22 (N)
THE USE OF POTABLE WATER CONTAINERS
7.22.1
Emergency/temporary supplies to individual customers will be
provided using bottled water.
Bottles must be stored in a cool place and out of direct sunlight
and should not be used once the sell by date has elapsed.
Yorkshire Water Services Ltd
additional, new or substitute clauses
7.23 (N)
DISINFECTION, FILLING AND USE OF BOWSERS
7.23.1
All Water bowsers used on Potable water works shall be
disinfection in accordance with the Company’s procedures
described in the Level 2 Water Quality manual in IMS 202.4.07.
Yorkshire Water Services Ltd
additional, new or substitute clauses
7.24 (N)
PRESSURE TESTING OF SERVICE PIPES
7.24.1
All services will be tested by filling with potable water and
applying water pressure after all connections are made between
the stop tap and the main prior to cutting a hole through the
main.
7.24.2
Hydraulic pressure for the test should be applied through an
adaptor connected in place of the cap on the tapping tee or other
approved method.
7.24.3
The service pipe will be tested by applying a water pressure
equivalent to either the SDR pressure rating of the pipe, or 1.5
x normal ‘working’ operating pressure. The lowest of the two
calculated pressures shall be used to test the service pipe. All
joints should be visually inspected for leakage whilst the
pressure is maintained. The pressure need only be maintained
for a period sufficient to allow inspection of all joints and to
demonstrate that the pressure is holding.
7.24.4
When a leak has been identified on a mechanical seal, the
Contractor may de-pressurise the assembly and re-assemble
the fitting. When the leak is at a welded joint then the joint shall
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be replaced with a new fitting. In both cases a new test should
be conducted.
Yorkshire Water Services Ltd
additional, new or substitute clauses
7.24.5
The Contractor shall inform YW staff of the time and date of
these tests and must give an opportunity for them to be
witnessed and approved.
7.25 (N)
REGULATORY POTABLE WATER SAMPLE POINTS
7.25.1
A basic Regulatory Sample Point (RSP) installation comprises
of the following principle items:•
Housing
•
Ferule connection to main
•
Cast Concrete base
•
LPC 3/4 rated sample cabinet
•
Copper Sample Line with Isolation valve
•
Sampling Bibcock
•
Drainage.
•
Labelling
The description of each of the component parts are detailed
below.
7.25.2
The hydraulic connection point and type of sampling facility shall
be recorded on IMS for all new and modified assets.
7.25.3
The Regulatory Sample Point shall located on the outlet of the
installation and shall be representative of the water leaving the
asset at all times and shall be capable of delivering an
uninterrupted continuous flow at all times. The sample point will
be hydraulically positioned to allow a sample to be collected at
30% to 100% full.
7.25.4
The sample point shall be located in a suitable location which is
free from potential contamination and reduces the risk of
external damage by weather or malicious damage. It shall be
accessible at all times.
7.25.5
All RSPs shall be located in a purpose built building suitable for
sampling. Where an external sample cabinet is required it shall
be placed in a safe location and be fixed securely to a concrete
base. Any external sample cabinet shall meet the following
minimum size requirements to provide shelter of the sample
from the prevailing weather conditions. The cabinet must be
W600mm x D400mm x H1200mm. See also Section 03.03
Outdoor Kiosks.
7.25.6
The sample point ferrule connection must be on a representative
feed from the storage facility or Water Treatment Works and
shall be located within the isolation of the facility. It shall allow
the full and complete mixing of the feed water. The tapping on
the main shall be a side tapping at 90o or 270o and carried out
using a Gun metal ferrule only. Any connections shall be carried
out by authorised personal according to Yorkshire water
procedure held on the IMS for the installation of new fittings
(3.2).207.3.01 and water quality procedures for the disinfection
of new mains fixtures and fittings (4.2) 202.4.02 & (4.2) 202.4.05
7.25.7
All new sample lines shall be 15mm WRAS approved DHC
(EN1057) Copper. All external connections shall have WRAS
approved compression fittings (EN1254) only.
7.25.8
In all instances the sample line shall not exceed 10 metres in
length and be dedicated and discrete to the sample point (i.e.:
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the sample point shall not be used for any other purpose and
shall not have any “dead legs” or connections to instrumentation.
The line shall meet minimum velocity requirements of 4 turnover
of the sample line in 2 minutes which equates to a 0.36 m/s
velocity.
7.25.9
All sample lines shall be fitted with a stainless steel isolation
valve or a ferrule connection which can be accessed without
restriction.
7.25.10
Any connections shall be carried out by authorised personal
according to Yorkshire water procedure on IMS for the
installation of new fittings (3.2).207.3.01 and water quality
procedures for the disinfection of new mains fixtures and fittings
(4.2) 202.4.02 & (4.2) 202.4.05
7.25.11
All sample points shall be gravity supplied. No hydraulic
pumping is permitted.
7.25.12
All water services and water fittings shall be protected from frost
and heat gain so far as reasonably practicable. In the case of
Regulatory Sampling Points potential damage shall be removed
by placing the sample point in a secure heated space. In addition
to this the line shall be lagged.
7.25.13
Where the sample line is external and it is not possible to protect
the line with heating it shall be insulated using closed cell type
lagging complying with BS5422 & in accordance with BS5970
up to a depth of 500mm below ground level.
7.25.14
On any new installation the height of the tap shall be 1000mm
from the base of the cabinet to reduce any risk of contamination
from the ground.
7.25.15
On existing sampling facilities the minimum permissible height is
500 mm from base of the cabinet. The height shall be assessed
on a case by case basis by a water quality representative for the
risk of contamination and altered accordingly.
7.25.16
The distance between the tap and tundish shall be no less than
300mm to allow full range of sampling bottles to be sampled
from.
7.25.17
The sampling point shall have a backboard made from a suitable
material which will allow the fixing of the regulatory label, tap,
burn plate and tundish. The backboard will withstand damp
environments and be mould resistant. The sampling point shall
also have a burn plate to protect the backboard from damage
during the sterilisation process. The burn plate shall be made of
Stainless steel and be of a sufficient size to allow easy flaming
of the tap.
7.25.18
The sampling point shall be drained away using a suitable
tundish which reduces splash back to a minimum. The waste
pipe shall drain to a suitable sump or soak away and be fitted
with an anti - insect screen mesh.
7.25.19
All newly installed or modified regulatory sample point items
shall be commissioned to demonstrate reliability in operation
and control under the specified conditions. The sample flow will
be sampled as set out below dependant on nature of
modification. The failure of the plant to operate correctly, or
failure of final effluent samples taken to measure performance
of the plant, shall be deemed a failure of the commissioning
requirements.
7.25.20
For new sample installations / line Installations / >10% line
modification the effluent will be sampled with two separate
events on separate dates to ensure that the point is
contamination free prior to use as a regulatory sample point. The
Water quality parameters to be sampled are as follows:
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Section 7 – Testing and Disinfection
Event 1
2 minute flushed sample:
Physicals, Bacti for Coliforms/Ecoli, NLF & Clostridia
Event 2
7.25.21
7.25.22
Grab
Physicals & Flushed Metals
30 second
Physicals & Flushed Metals
1 minute
Physicals & Flushed Metals
2 minute
Physicals, Bacti for Coliforms/Ecoli, NLF’s 2 & 3
Day TVC, Clostridia, Taste & Odour & Flushed
Metals
5 minute
Physicals & Flushed Metals
10 minute
Physicals Bacti for Coliforms/Ecoli, NLF’s 2 & 3
Day TVC, Clostridia, Taste & Odour & Flushed
Metals
For any new installation or modification of tap height will require
a flow test to ensure that it meets asset standard. The sample
velocity needs to meet minimum 0.36m/s and therefore achieve
the required minimum two turnovers of the sample line at the
maximum length of 10m.
Following any repair/modification to the hydraulic connection a
commissioning sample of the effluent must be collected to prove
that that water quality is representative of the asset being
sampled.
Sample requirement:
2 minute flushed sample for Coliforms/E. coli/Clostridia,
physicals
CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
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Section 8 – Roadworks
SECTION 8
ROADWORKS
The Notes for Guidance are not part of
the Specification.
(i) This Section is not intended to cover
the construction of prospectively
adoptable highways but, together with
the relevant Materials Clauses, is based
generally on the requirements of the
‘Specification for Highway Works',
published by the Highways Agency,
abbreviated and simplified to take
account of the type of road normally
required in association with Water
Industry work.
8.1 ROAD FORMATIONS
(i) A cross-section of the carriageway
construction and the position and type of
any joints, should be described in the
Contract.
1. The road formation shall be the surface obtained after completion of any
earthworks.
2. Formations, immediately before being covered with sub-base or road base
material, shall be clean, free from mud and slurry and properly shaped and
compacted to an even and uniform surface.
3. The preparation and surface treatment of formations shall be carried out
after the reinstatement of any excavations for services.
4. The formation shall be compacted so that the dry density of the upper 150
mm of the ground or fill is less than 95% of the maximum dry density,
determined in accordance with Section 4 of BS 1377-4. Where the formation
is in natural ground, the compaction shall, whenever possible, be carried out
at or near the natural moisture of the ground.
8.2 SUB-BASE CONSTRUCTION
(i) The use of approved recycled
materials is actively encouraged.
(ii) If a lean-mix concrete sub-base is
required, this should be described in the
Contract.
1. Within 48 hours of completion of a road formation, granular sub-base
material shall be spread and compacted to the required thickness. The subbase shall be protected from deterioration due to ingress of water, the
adverse effects of weather and the use of construction equipment.
Compaction shall be carried out in accordance with the relevant Highway
Reinstatement Specification.
8.3 WET-MIX MACADAM CONSTRUCTION
1. Wet-mix macadam shall be spread evenly on the sub-base and
compacted in layers of not more than 200 mm thickness at the optimum
moisture content ± 0.5%.
2. Spreading shall be undertaken concurrently with placing. Compaction
shall be completed as soon as possible after the material has been spread
and carried out in accordance with the relevant Highway Reinstatement
Specification.
8.4 LEAN CONCRETE CONSTRUCTION
1. Lean concrete construction for roads shall be GEN1 and shall be spread
evenly on the sub-base and laid and compacted in layers of not more than
200 mm thickness.
2. Spreading shall be undertaken concurrently with placing. Compaction
shall be completed as soon as possible after the material has been spread
and carried out in accordance with the relevant Highway Reinstatement
Specification. The maximum period of time between mixing of the materials
and final compacting of any given material shall be 2 hours.
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3. Where practicable, joints against hardened material shall be avoided.
Where such joints are unavoidable, the hardened material shall be cut back
vertically for the full depth of the layer before placing any further adjacent
material.
4. Lean concrete shall be cured for a period of not less than 7 days. No
vehicular traffic shall be allowed to run on the base during this time.
8.5 LAYING COATED MACADAM
1. Transportation, laying and compaction of all coated macadam shall be
carried out in accordance with the relevant provisions of BS 594987.
2. Where laying against an exposed edge, the joint shall be treated with an
application of bitumen conforming to BS EN 12591 Grade 100/150.
8.6 LAYING HOT ROLLED ASPHALT
1. Transportation, laying and compaction of hot rolled asphalt shall be
carried out in accordance with the relevant provisions of BS 594987.
2. Where laying against an exposed edge, the joint shall be treated with an
application of bitumen conforming to BS EN 12591 Grade 100/150.
8.7 WATERPROOF UNDERLAY FOR CONCRETE CARRIAGEWAYS
1. Waterproof underlay shall consist of waterproof paper or impermeable
plastic sheeting, laid to provide a membrane immediately below the
concrete. Overlaps shall be not less than 300 mm and precautions shall be
taken to prevent ponding on the membrane.
8.8 REINFORCEMENT OF CONCRETE CARRIAGEWAYS
(i) This Clause assumes that only a
single layer of reinforcement is
necessary.
1. Reinforcement in concrete carriageways shall be so placed that, after
compaction of the concrete, its cover below the finished surface of the slab
is 60 mm (± 10 mm) and it terminates 125 mm (± 25 mm) from the edges of
the slab and from all pre-formed joints in the concrete.
2. At transverse joints between mats of steel fabric reinforcement, the
longitudinal bars shall overlap by at least 35 times the bar diameter, provided
that such overlap shall not, in any case, be less than 450 mm. Mats shall be
placed so as to maintain the same spacing between edge longitudinal bars
as in the body of the mat.
3. Reinforcement shall be positioned above dowel bars and tie bars,
irrespective of the tolerances on position.
8.9 LAYING CONCRETE CARRIAGEWAYS
(i) The positioning and detailing of
movement joints should be described in
the Contract.
1. Placing, compacting and finishing of concrete in carriageways shall be
carried out in one layer as rapidly as possible and shall be so arranged that,
in any transverse section, the time for completion of mixing the first batch of
concrete to completion of compaction of that section shall not exceed 2
hours.
2. Carriageway surfaces shall have a screeded finish, which shall be
brushed transversely to produce a lightly brushmarked finish, with a 100 mm
arris steel trowel finish to sides and at joints.
3. Surface irregularities shall not exceed 3 mm when checked with a 3 m
straight edge.
8.10 LAYING KERBS AND CHANNELS
(i) Details of the concrete bed and
haunch should be described in the
Contract.
CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
1. Kerbs, edgings, channels and quadrants shall be laid and bedded on a
layer of Class M12 mortar, either on the concrete carriageway or on a GEN3
concrete foundation, as described in the Contract. They shall be butt-jointed,
except where they are laid on concrete carriageways. They shall be provided
with joints coincident with the carriageway movement joints, of width and
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Section 8 – Roadworks
with filler identical to that used in the carriageway joints. All kerbs shall be
backed with GEN3 concrete.
2. For radii of 12 m or less, kerbs and channels of the appropriate radius
shall be used.
3. Alignment of kerbs and channels shall not deviate by more than 10 mm
from that described in the Contract, with no lipping of visible faces.
8.11 FOUNDATIONS FOR FOOTWAYS
(i) A cross-section of the footway
construction should be described in the
Contract.
1. Foundations for footways shall consist of Type 1 granular sub-base
material, spread evenly and compacted in layers of not more than 100 mm
thickness.
2. Compaction to the correct levels shall be carried out using a vibratory
roller having a static load of at least 1000 kg per metre width of roll.
8.12 LAYING CONCRETE PAVING FLAGS
(i) Paving flags should not be laid on
ground which has been either excavated
below normal service depth or not
backfilled to Highway Reinstatement
Specification.
1. Precast concrete flags of 50 and 63 mm thickness (Types A, B, C or D
from BS EN 1339) shall be laid to the required falls on sub-base material, as
described in the Contract, and bonded with joints and fully bedded on mortar
in accordance with BS 7533-4.
2. Precast concrete paving flags 60, 65 or 70 mm thickness (Types E, F or
G from BS EN 1339) shall be laid to the required falls on sub-base material,
as described in the Contract, bonded with joints at right angles to the kerb
and bedded on sand-bed in accordance with BS 7533-4.
3. Flags shall be cut to fit around surface boxes and other furniture and, on
circular work where the radius is 12 m or less, shall be radially cut on both
edges to the required lines.
8.13 LAYING PAVING BLOCKS
1. Precast concrete block paving shall be laid in accordance with
BS 7533-3.
8.14 TOLERANCES FOR FINISHED CARRIAGEWAY SURFACES
1. Finished surfaces at each stage of road construction shall not vary from
the levels described in the Contract by more than the following permissible
tolerances:
Surface
Formation and sub-base
Base
Wearing surface or slab surface
Permissible Tolerance (mm)
+ 10, - 30
± 15
±6
2. The combination of permitted tolerances in the levels of different
pavement courses shall not result in a reduction in thickness of the
pavement, excluding the sub-base, by more than 15 mm from the specified
thickness, nor a reduction in the thickness of the bituminous wearing course
by more than 5 mm from that specified, and the maximum allowable
irregularity of the wearing surface below a 3 m straight edge shall be 3 mm.
3. Combinations of reverse tolerances shall not result in ponding of surface
water.
8.15 FIXING OF GULLIES
1. Gullies shall be bedded and surrounded with GEN3 concrete to the
thickness described in the Contract.
2. Frames shall be bedded in epoxy mortar on two courses of Class B
engineering brickwork or precast concrete gully cover slabs.
8.16 LINING AND SIGNAGE
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(i) Road traffic signs should be provided
in accordance with the the Traffic Signs
Regulations and General Directions,
2002, published by The Stationery
Office.
Section 8 – Roadworks
1. Permanent road markings shall be applied, in accordance with
BS 3262-3.
(ii) Deployment of traffic signs should be
as ‘Safety at Street Works and Road
Works, 2002, published by The
Stationery Office.
8.17 CONCRETE FOOTWAYS
1. Where in-situ concrete footways are constructed, the final surface shall
have a brush finish, with a minimum 60 mm smooth trowelled margin at the
edge.
Yorkshire Water Services Ltd additional,
new or substitute clauses
CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
8.17.1 (S)
Where in-situ concrete footways, steps and stairways are
constructed, the final surface shall have a brush finish, with a
60 mm smooth trowelled margin on each side excluding the
toe edge. Brushing to be parallel to the fall direction.
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Section 9 – Sewer Renovation
SECTION 9
SEWER RENOVATION
The Notes for Guidance are not part of
the Specification.
(i) This Section covers the fundamental
requirements of sewer renovation based
on the recommendations of the
‘Sewerage Rehabilitation Manual’, (5th
Edition), 2001 published by WRc plc.
(ii) The Contract
requirements for:
should
describe
(a) the interface with the existing
operational system to avoid unplanned
disruption of services to customers and
pollution incidents;
(b) dealing with any
aggressive effluents; and
unusually
(c) dealing with existing flows to maintain
levels of service.
(iii) Attention is directed to BS EN ISO
11296 'Plastics Piping Systems for
Renovation of Underground Nonpressure Drainage and Sewerage
Networks, Part 1: General, Part 2: Lining
with Continuous Pipes, Part 3: Lining
with Close Fit Pipes, Part 4: Lining with
Cured-in-place Pipes'.
(iv) Reference should be made to Report
UM 1464 'Typical Specifications for
Trenchless Technology Systems', 1995
published by WRc plc.
9.1 ISOLATION OF FLOWS
(i) Example flow schedules are given in
the ‘Sewerage Rehabilitation Manual’
(5th Edition), 2001 published by WRc
plc.
1. Flows shall be positively dealt with or isolated from the section being
renovated.
(ii) Where the Contractor will be
permitted to operate flow control devices
and isolate flows, this should be
described in the Contract.
Additional Clause
2. The Contractor shall take due regard of the weather forecast as supplied
by the Met Service for the closest weather station for the duration of the
intended isolation period.
9.2 PREPARATORY SURVEY
(i) Details of the structural condition
survey should be described in the
Contract.
1. The sewers to be renovated shall be surveyed to determine the position,
size and angle of approach of all laterals, to an accuracy appropriate to the
method of reconnection.
2. A survey of the structural condition of the sewers and associated flow
control devices shall be carried out.
3. All flow control devices shall be operable prior to the commencement of
sewer renovation works.
4. Prior to ordering any materials, the sewer dimensions shall be confirmed
from the survey.
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Section 9 – Sewer Renovation
5. Any sewer pressure main to be renovated shall be surveyed to determine
its position, size, material and structural condition, and the location and
operability of all fittings that may impede the insertion of the liner.
9.3 PREPARATION OF SEWERS
(i) The Contract should describe where
flow control devices may be operated.
1. Sewers to be renovated shall be prepared so that the installation and
performance of the renovation system is not impaired. The installation
method and preparation shall not affect the stability of the existing sewer.
2. Debris shall be prevented from being carried downstream whilst preparing
or working in existing sewers. Such debris is to be removed from the sewer.
3. Intruding laterals shall be finished flush prior to the application of any lining
system.
4. Loose or unsound brickwork or masonry in man-entry sewers shall be
repaired using Class A engineering bricks and Class M12 mortar, with all
joints completely filled before other phases of rehabilitation.
5. All substrate surfaces shall be stated in the Contract.
6. Pressure pipelines shall be thoroughly cleaned to remove all rust,
tuberculation, deposits, loose or deteriorated remains of any original
coatings and other foreign materials from the inside of the pipe, to produce
a smooth surface finish.
7. Valves, bends and other fittings shall be removed, as appropriate, to
enable the liner to be correctly installed.
9.4 JOINTING GENERALLY
1. Jointing surfaces and components shall be kept clean and free from
extraneous matter until the joints have been made or assembled.
9.5 CONNECTIONS
(i) The period between sewer lining and
reconnection of laterals should be
described in the Contract.
1. All laterals and branches shall be reconnected following sewer renovation
works. Any circumferential lining joints shall not be made at, or within
100 mm of, a connection.
2. Each finished connection shall be made flush with the lining and shall
provide a smooth transition.
3. Cured-in-place lateral connection collars (“Top Hats”) shall be Class B in
accordance with BS EN ISO 11296-4: 2011. The rim shall extend for more
than 50% of the circumference of the main pipe.
9.6 CHAMBERS
1. In chambers, where applicable, the edges of the lining shall be adequately
sealed and the benching made good.
2. Brick chambers shall be repaired with Class B Engineering bricks bedded
on Class M12 mortar.
3. Exposed edges or ends of plastics liners shall be mechanically anchored.
9.7 RELEASE OF CURING WATER
(i) Due regard must be paid to the
disposal of curing liquors to avoid
pollution.
(ii) The Environment Agency, SEPA and
NIEA provide advice to industry and the
public on their legal responsibilities and
good environmental practice through a
series of Pollution Prevention Guidance
1. Whenever hot water curing of a lining system is carried out, the water shall
not be released until it cools below 40°C.
2. Prior approval from the Client shall be obtained before the release of
curing water.
Notes (PPGs), see www.environmentagency.gov.uk.
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Section 9 – Sewer Renovation
9.8 ANNULUS GROUTING GENERALLY
(i) Any alternative restrictions on
maximum grout pressures should be
described in the Contract.
(ii) The grouting materials should be
detailed in the Contract.
1. All air, water and contaminated grout are to be expelled from the annulus
by the grouting process.
2. The grout injection pressure shall be continuously measured by a suitable
gauge and shall not exceed 50 kN/m2.
3. The quantity of grout injected at each injection point and the maximum
pressure at the nozzle at that point shall be recorded.
4. Disposal of grout to live sewers is not permitted.
5. Annulus grouting shall closely follow the placing of any lining segments.
6. The applied grouting pressure shall not exceed the design external
pressure for the liner unless the liner is internally pressurised during grouting
or other internal support provided.
Yorkshire Water Services Ltd additional,
new or substitute clauses
9.8.7 (A)
The Contractor shall submit for approval, the proposed
method of ensuring the calculated volume of grout is
monitored and delivered within stated tolerances. The
Contractor shall react immediately to correct any defect (over
or under delivery) as set out in his Method Statement.
9.9 INSPECTION AFTER GROUTING
1. The main sewer, branches or laterals shall be inspected immediately after
each grouting operation and any excess grout cleaned out.
9.10 LINING THROUGH FLOW CONTROL DEVICES
1. Any flow control devices lined in-situ shall be operated throughout their
full travel, several times immediately after lining, in order to ensure free
operation.
9.11 INSPECTION AFTER RENOVATION
(i) The format of the information required,
and any need for a CCTV survey, should
be described in the Contract.
(ii) The number of samples to be
removed and the length of the sample
should be described in the Contract.
Where appropriate, a control sample
should be provided, in advance of the
renovation commencing, to compare
with samples taken at completion.
1. On completion of the renovation, a survey shall be undertaken and a
record of that survey provided to the Client. Where man-entry is not possible,
a CCTV survey shall be carried out, including the use of a pan and tilt
camera, where laterals are included in the length concerned.
2. Pipe samples shall be taken to check lining performance and to determine
the thickness. The lining shall be made good after the samples have been
taken. The monitoring of renovation will be used to determine the location of
samples. The pipe samples shall be provided to the Client.
3. The method of localised air testing shall be in accordance with Clause 13
of BS EN 1610:2015.
(iii) The sampling and acceptance of
cured-in-place lateral connection collars
should be as detailed in the Contract.
9.12 LINING TEMPLATE
1. For man-entry sewers, a lining template shall be drawn through the sewer
prior to ordering the lining to “prove” the suitability of the profile. If necessary,
the template shall be adjusted and the proving operation repeated until a
suitable profile is established.
2. For non-man-entry sewers, immediately prior to installation a proving pig
with solid ends of sufficient rigidity and length to represent the proposed
lining system shall be passed down the sewer length to be relined.
9.13 LINING DESIGN
1. The lining design shall be in accordance with the ‘Sewerage Rehabilitation
Manual’ (5th Edition), 2001, published by WRc plc.
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Section 9 – Sewer Renovation
9.14 TOLERANCES FOR PREFORMED LININGS
1. The position of the internal face of any unit shall not deviate by more than
± 20 mm from the agreed profile. No section of lining shall have a backfall.
2. Lipping between adjacent units shall not exceed 5 mm.
9.15 CUTTING AND PROTECTION OF LININGS
1. Linings shall be cut in accordance with the manufacturer’s instructions.
2. Cut edges of GRP shall be sealed in accordance with WIS 4-34-02.
3. The ends of polyethylene and polypropylene linings shall be mechanically
anchored using suitable fixings.
4. At the upstream end of the lining, the original invert shall be broken out
and the lining unit laid on a Class M12 mortar bed so that the inverts of the
lining and the host pipe are correctly aligned.
9.16 MAN-ENTRY PREFORMED GRP AND GRC UNITS
1. Each lining unit shall be laid to the mean line and level of the existing
sewer and be packed, in a minimum of four suitably-spaced positions, with
chemically inert spacers of no greater strength than the grout used to fill the
annulus.
2. The annulus shall not be less than 10 mm in width.
9.17 CURED-IN-PLACE LINING SYSTEMS
1. All cured-in-place linings shall be designed, manufactured, constructed,
tested, inspected and certified in accordance with BS EN ISO 11296-4:
2011.
2. Cured-in-place linings for resisting infiltration shall pass the leak tightness
test set out in WRc plc Report CP308 ‘Procedures for Testing the Capability
of Cured-in-place Pipe (CIPP) Lining Systems to Resist Infiltration’.
9.18 RENDERING AND LOCAL REPAIRS
(i) Any requirements for rendering and
local repairs should be described in the
Contract.
1. All bricks intruding into the barrel shall be removed and replaced from
inside the sewer.
9.19 PATCH REPAIRS
1. Cured-in-place patch repairs shall be leaktight and shall comply with
WIS 4-34-06.
2. The materials used to fabricate the patch shall conform to the requirements
of Clause 4.2 of WIS 4-34-06:2010.
3. The patch linings shall be fabricated in accordance with Clause 4.3 of
WIS 4-34-06:2010.
4. The materials used for cured-in-place patch repairs for structural
enhancement shall incorporate a means of anchorage that will continue to
function after all initial shrinkage has occurred.
5. Where a complete pipe length (from joint to joint) requires a repair, the
patch shall extend the full length of the pipe (joint to joint) and beyond the
pipe joints by a minimum of 100 mm.
6. Where a repair is required within a pipe length, the repair shall extend by
a minimum of 100 mm either side of the defect, except where the repair
crosses a joint, then Clause 9.19.5 shall apply.
7. Where it is necessary to overlap patches, the overlap shall be a minimum
of 150 mm.
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Section 9 – Sewer Renovation
8. The Contractor shall specify the method of installation in accordance with
Clause 4.3 of WIS 4-34-06:2010.
9.20 STYRENE FUMES
(i) To prevent styrene fumes being
forced into laterals and properties, air
extraction should be used to draw the
fumes out of the sewer from the working
manhole. Extractor fans should ventilate
the lined sewer from upstream to
downstream.
1. The Contractor shall take all precautions to prevent styrene fumes from
cured-in-place linings or patch repairs entering the properties via their
laterals. A suitable monitor to measure the styrene fumes level shall also be
available on Site.
9.21 SPRAY LINING
(i) In the absence of a standard for spray
polymeric
linings
for
wastewater
applications, the guidance given in BS
EN 13566 should be followed.
1. Dimensional requirements, material tests and measurements are to be in
accordance with BS EN ISO 11296-4: 2011 .
(ii) The method of testing polymeric
spray linings should be as stated in the
Contract.
Yorkshire Water Services Ltd additional,
new or substitute clauses
CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
9.22 (N)
SEWER HANDOVER
9.22.1
For all works on live sewers the Contractor shall comply with
the requirements of the Yorkshire Water Sewer Handover
Procedure.
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Yorkshire Water Engineering Specification
Section 10 – Water Mains Renovation
SECTION 10
WATER MAINS RENOVATION
The Notes for Guidance are not part of
the Specification.
(i) This Section covers the fundamental
requirements
of
water
mains
rehabilitation
based
on
the
recommendations of the ‘Water Mains
Rehabilitation Manual’, 1999, published
by WRc plc.
(ii) The Contract
requirements for:
should
describe
(a) the interface with the existing
operational system to avoid unplanned
disruption of services to customers and
pollution incidents;
(b) dealing with existing flows to
maintain levels of service; and
(c) where valves and hydrants may be
operated.
10.1 PREPARATORY SURVEY
1. The water mains to be rehabilitated shall be surveyed to determine their
position, size, material and structural condition, and the location and
operability of all fittings.
Yorkshire Water Services Ltd additional,
new or substitute clauses
10.1.2 (A)
In addition to work instructed by the Employer, the Contractor
may carry out such preparatory survey and further trial holing
as he considers necessary for his own purposes to facilitate
the planned and efficient execution of the scheme, but this
additional work shall be deemed to be covered by the items in
the Schedule of Rates for mainlaying and renovation.
10.1.3 (A)
The Contractor will be expected to provide trained staff to
locate and mark up existing apparatus in advance of the main
and service works by means of electronic detection
equipment.
10.1.4 (A)
The position and number of trial holes required shall be
agreed jointly between the Employer and the Contractor. Trial
holes shall be carried out sufficiently in advance of the main
works to ensure that any enabling works identified can be
undertaken without causing any delay to the programme.
10.1.5 (A)
A hydrant camera will be used across the area that is being
investigated to determine whether ductile iron and cast iron
pipes are lined and whether there are sedimentary deposits in
other mains. The initial investigation will be used to gain
information for a more targeted pipe sampling programme and
will provide information to prevent the proposed lining of mains
that already have a lining or are not suitable for lining because
of their structural condition. The extent of the hydrant camera
survey will be determined by the project core team. All of the
information obtained from the hydrant camera programme will
be included in the Investigation Report.
10.1.6 (A)
The Employer is committed to undertaking work on the
network without interrupting supplies to its customers. As part
of this initiative no pipe samples are now taken from mains
except in rare cases where circumstances dictate. The
process for obtaining information about the condition of pipes
is set out below.
CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
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10.1.7 (A)
Section 10 – Water Mains Renovation
The sample programmes shall be agreed with the Employer
and shall take onto account the need to take representative
samples of all mains in the area that is being investigated and
the information that has been obtained from the hydrant
camera survey. In practice this usually means a sample
approximately every 500m in urban areas and every 1000m
in rural areas.
10.1.8 (A)
The process on site will involve excavation down to and
around the pipe followed by the cleaning of soil from the pipe
bore. At this point a visual inspection of the main will
determine if the pipe is in a good enough structural condition
for couponing to take place. If not then a physical pipe sample
will be required at a later date when the required warning
notices to customers have been served. Firstly an ultrasonic
scan will be taken over the full bore of the pipe over a length
of approximately 300mm. Then an under-pressure tapping will
be used to take a coupon to determine the lining, if any, of the
pipe and a camera inserted to view the condition of the pipe
along its bore.The tapping is then sealed and the excavation
is backfilled.
10.1.9 (A)
The information obtained from the above field investigation will
be used to produce a report with proposals for the required
form of mains rehabilitation for the main. The decision whether
the main needs to be renewed, lined, cleaned or no action
taken shall be carried out in accordance with guidance
outlined in Yorkshire Water’s Technical Approach on Mains
Rehabilitation in QMS.
10.2 PREPARATION OF WATER MAINS
1. Water mains to be re-lined shall be prepared internally such that the
performance of the lining system is not impaired.
Yorkshire Water Services Ltd additional,
new or substitute clauses
10.2.2 (A)
During a refurbishment of a section of main it may become
evident that items of existing apparatus, notably valves and
hydrants, are defective and shall replaced in order to realise
the full benefit of the scheme.
10.3 IN-SITU LININGS
(i) Due regard should be paid to the
release of toxic gases and odours from
the installation of epoxy lining systems.
1. The measures to be taken to control the release of odours and gases
arising from the Works shall be stated in the Contract.
2. The in-situ lining of water mains with epoxy resin shall be in accordance
with the, ‘Code of Practice: In-situ Resin Linings of Water Mains (IGN 4-0202) and Operational Requirements: In-situ Resin Lining of Water Mains
(WIS 4-02-01) published by Water UK.
3. The in-situ lining of water mains with cement mortar shall be in accordance
with the ‘In-situ Cement Mortar Lining – Operational Guidelines and Code of
Practice’, published by WRc plc.
4. The in-situ lining of water mains with polymeric linings shall be in
accordance with the ‘Code of Practice: In-situ Resin Linings of Water Mains
(IGN 4-02-02) and the Operational Requirements: In-situ Resin Lining of
Water Mains (WIS 4-02-01), published by Water UK.
Yorkshire Water Services Ltd additional,
new or substitute clauses
10.3.5 (A)
It is Yorkshire Water’s policy to spray line through tees where
possible but this does not preclude the renewal of attached
valves and hydrants if deemed necessary.
10.4 SLIPLINING AND REPLACEMENT MOLING
(i) The period between pipe lining and
reconnection of services should be
described in the Contract.
1. The use of sliplining and moling techniques shall be in accordance with
‘Sliplining and Replacement Moling of Water Mains – Operational Guidelines’
published by WRc plc.
2. The annular void shall be grouted unless otherwise stated in the Contract.
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10.5 CONNECTIONS
1. Service connections shall be disconnected and reconnected, as required,
for the work.
10.6 LINING THROUGH VALVES
1. Any valves lined in-situ shall be operated throughout their full travel,
several times immediately after lining, in order to ensure free operation.
There shall be no in-situ lining through valves of pipelines of non-man-entry
sizes.
10.7 INSPECTION AFTER IN-SITU RE-LINING
(i) The format of the information required
and CCTV survey should be described
in the Contract.
(ii) The number of samples to be
removed and the length of the sample
should be described in the Contract.
Where appropriate, a control sample
should be provided, in advance of the
renovation commencing, to compare
with samples taken at completion.
1. On completion of the rehabilitation, a survey shall be undertaken and a
record of that survey shall be supplied to the Client.
2. Pipe samples shall be taken and provided to the Client in order to check
lining performance and to determine thickness. The lining shall be made
good after the samples have been taken. The monitoring of rehabilitation will
be used to determine the location of samples.
10.8 BRINGING REHABILITATED WATER MAINS INTO SERVICE
1. Before returning any rehabilitated water main into service, the main shall
be cleaned and disinfected.
Yorkshire Water Services Ltd additional,
new or substitute clauses
10.9 (N)
RAPID SETTING POLYMERIC LINING
General
10.9.1
All rapid setting polymeric lining shall be carried out by a
Contractor approved on behalf of the DWI for the purpose in
accordance with the requirements of the Water Industry
Specification and Information and Guidance Notes for in-situ
lining of water mains. This incorporates the use of approved
materials and an approved contractor who is operating an ISO
9002 Quality System in association with an accredited third
party certification body.
10.9.2
The clauses of the Water Industry Specification and
Information and Guidance Notes together with such additional
requirements as detailed within this document form the
complete specification for the technique and shall be complied
with at all times.
10.9.3
It is these actions were set out on the basis that they will be
completed within 10 hours.
10.9.4
In acceptable circumstances unlined mains will be allowed to
be put back into supply so that the warning period is not
exceeded. In these cases a flow of water will be maintained
through the unlined pipe at all timers by use of an opened
hydrant.
10.9.5
The Contractor shall be formally approved by a certifying
organisation on behalf of the Nominated Body and shall
supply trained and certified personnel, approved materials
and a certified lining rig to apply the polyurethane in
accordance with the Water Industry Specification and
Information and Guidance Notes.
10.9.6
Prior to the commencement of any lining operations the
Contractor shall provide the Project Manager with the
following details which shall be complied with throughout the
contract period:
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1)
Section 10 – Water Mains Renovation
The Instructions for Use (IFU) documentation for such
rapid-setting systems to include details of the material
mix ratio, cure regime, application temperatures, storage
requirements and health and safety data sheets.
2)
Documentary evidence that, as a minimum the Site
Agent, Foreman, Rig Operator and Application Head
Operator for each lining site are direct employees of the
Contractor and that these staff have been fully trained
and have been deemed competent by a suitably
approved organisation. At least 3 key personnel shall be
on site for each entire cleaning and application operation.
Any fitter attending the site shall also be certified to work
on the rig in question.
3)
Documentary evidence of the ability to apply rapid-setting
polymeric linings correctly. Such evidence shall indicate
the date of such approval and the proposed date of the
renewal. The Contractor shall ensure that approval is not
allowed to lapse.
4)
Details of the lining rig design, monitoring system,
delivery hose, in line mixer and lining application head
and documentary evidence of the relevant approved
assessment for such machinery.
5)
Details of any sub-contracting organisation to be used
part of the rehabilitation process though not directly
cleaning or applying rapid-setting polymeric linings to
water mains.
Any changes to these criteria shall notify in writing to the
Project Manager for approval at least one month prior to such
amendments taking place.
10.9.7
The Contractor shall be permitted to sub-contract the rapidsetting polymeric lining works to an alternative contractor as
long as such an organisation is fully able to comply with the
requirements of the specification and is fully approved in
writing by the Project Manager.
10.9.8
Each lining rig will be regularly audited by an independent
organisation and YW audits will also be made on all lining
operations.
10.9.9
Lining products shall be procured through the existing
framework agreement.
10.9.10
The equipment to clean and line water mains with rapidsetting polymeric material shall permit the workers to follow
the procedures and obtain results described in the Water
Industry Specification and Information and Guidance Notes.
10.9.11
For all diameters of main the rapid-setting polymeric material
shall be centrifugally spray applied to the bore of the pipe.
10.9.12
The minimum thickness for standard rapid polymeric lining is
1mm for mains up to 450mm diameter. For mains equal to or
greater than 450mm in nominal diameter the minimum
thickness is 1.5mm.
10.9.13
Semi-structural rapid setting polymeric lining shall not be used
for the rehabilitation of pipes with a structural scheme driver.
When semi-structural rapid-setting polymeric product is
applied for water quality purposes only it shall be applied at a
minimum thickness of 2mm.
10.9.14
The Utility Representative shall be provided with all calibration
details and schedules and all components in the schedule
shall be suitably labelled indicating dates of the last calibration
and proposed re-calibration. The lining rig shall not be
operated if these requirements are not in place.10.9.15
The Contractor shall plan his operations so that access
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(i) Air Vortex cleaning technique is
used on mains up to and including
300mm in diameter, above this
diameter
alternative
cleaning
techniques should be considered.
Section 10 – Water Mains Renovation
excavations coincide wherever possible with valves and
fittings that are to be replaced and/or installed.
10.9.16
Any temporary by-pass and pipework required shall be
suitably installed and secured prior to any work commencing.
10.9.17
Excavations shall be of a suitable size to adequately gain clear
access to the water main.
10.9.18
After adequate notification has been given to any customers
that are affected, the main to be lined shall be isolated by the
operation of the appropriate valves. In addition stop taps shall
be located by the Contractor, their operation checked and any
problem with their operation or condition of the furniture to be
reported as part of the detailed design proposal. The
Contractor will be responsible for closing stop taps prior to
cleaning and re-opening for returning the main to service. All
efforts should be made to not interrupt customers’ supplies
during the lining operation by the use on innovative supply
techniques and good design practice.
10.9.19
Prior to cutting into the main it will be tapped live to ensure
that it is a water main.
10.9.20
Prior to lining with polyurethane the pipe will be cleaned by an
air vortex low water use pipe cleaning technique. This involves
blowing aggregate down the pipe at high speed until all
tuberculations, deposits, loose or deteriorated remains of a
previous coating and other foreign materials from inside the
pipe have been removed. Where it is not appropriate or
possible to use this technique then consideration will be given
to using more traditional cleaning technologies such as rack
feed boring or drag scraping as agreed by the Core Team.
The cleaning method chosen shall not remove areas of
graphitisation and shall leave the bore of the pipe smooth,
intact and free from dust to ensure a secure bond for any spray
lining to be applied, or not to provide any sharp promontories
which may damage the lining.
10.9.21
The aggregate used shall be dust free and only contain dry
granite or flint that meets the equipment manufacturer’s
specification. The aggregate and removed deposits will be
collected in an enclosed vessel at the end of the main, and
upon completion of the cleaning of the pipe the contents of the
vessel will be disposed of in an environmentally safe manner.
10.9.22
Suitable precautions must be taken to protect operatives and
the public from injury during the use of all types of cleaning
equipment.
10.9.23
Although the air vortex method of cleaning, does not typically
require settling tanks (as there is no effluent) on occasions
when settling tanks are required they shall be of a suitable size
and capacity and shall be used to initially remove all coarse
debris from the discharge water before it is disposed of. In
addition a further level of treatment will be required such as
flocculation or fine screening to remove fine debris from the
discharge water. Discharge of water must be with the written
approval of and in accordance with the requirements of the
Environmental Agency and/or sewerage undertaker. All solid
debris will be removed from site to an approved tip.
10.9.24
In order to ensure an approved application and suitable bond
between the host material and the new polymeric lining during
in-situ spray or blown lining operations one of the following
methods should be adopted to avoid moisture or dew forming
on the substrate and becoming trapped between the lining and
the host substrate.
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•
•
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The substrate shall be heated to a temperature at least
5 deg C above the ambient temperature of the
environment in which the lining is being applied or
The atmosphere within the pipe immediately before the
application shall have a dewpoint/moisture content less
than 900ppm.
10.9.27
The materials shall be heated, applied and cured in
accordance with the requirements provided by the
manufacturer and the Water Industry Specification and
Information and Guidance Notes including for mixing using an
approved static mixer.
10.9.28
The minimum spin-up time shall be that determined by the
resin manufacturer.
10.9.29
The Contractor shall take all reasonable precautions to
prevent blockages occurring in service pipes and internal
pipework. The Contractor shall be responsible for clearing
blockages to ferrules, communication pipes, stop taps,
meters, service and internal pipework and appliances
following scraping and lining of the main supplying such
premises. To minimise the likelihood of blocking service pipes
the Contractor shall take the following actions.
10.9.30
An appropriate vacuum generating pump shall be installed at
one end of the pipe with a cap end at the other end after
cleaning has taken place but before lining commences. A
negative pressure shall be applied to the pipe and the stoptaps opened to draw any material from the service pipe and
into the main. The stop taps shall then be shut and equipment
disconnected from the main. Any debris shall then be cleaned
from the main prior to lining. This process shall be employed
for all linings whether the presence of debris is apparent or
not.
10.9.31
After lining but before disinfection a flexible cutter machine,
shall be used to unblock any ferrules that have been coated
with resin. The camera on the flexible cutter shall be used to
ascertain if a ferrule is blocked and if that is the case then the
cutter shall be used to drill out the obstruction. The drilled out
resin shall then be cleaned away prior to disinfection.
10.9.32
After these actions have been taken if there are still blockages
to a customer supply then the Contractor shall take immediate
steps to clear such blockages using a reputable qualified
plumber as necessary. It should be noted that blockages and
supply problems do not always come to light immediately
following renovation work and such occurrences may be
reported outside normal working hours.
10.9.33
Following the cure period the Contractor shall conduct a
colour CCTV survey of each lining length.
10.9.34
Full details of each lining length and critical aspects of the
lining quality shall be recorded on the lining record sheet,
signed by the Contractor and supplied to the Project Manager.
These records shall enable the quality of the works to be
audited at any time.
10.9.35
The main shall be chlorinated in accordance with Clause 7.11
(27-35) of this specification.
10.9.36
After disinfection the main shall be flushed for the period
stated in the manufacturer’s IFU, or if no period is stated then
for a period of one hour at 0.5m/s or available mains velocity
before return to service. Chlorine concentrations shall be
checked to confirm they have returned to background
concentrations.
10.9.37
Where lining defects or failures occur either on the rig
printouts or the actual lining remedial works are required. For
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the purpose of this contract the following remedial actions are
the minimum requirements expected by the Project Manager
and are not to be challenged or compromised, failure to
comply with them could ultimately lead to the suspension of a
lining gang and/or key personnel for a period to be defined by
the Project Manager.
10.9.38
Any incident regarding out of specification mix ratio shall be
rectified immediately. The acceptable tolerance on
manufacturer’s mix ratio is +/- 5%; any reading outside of such
tolerances requires positive action. The minimum acceptable
actions are post lining weight checks and a pipe sample at the
location where the mix ratio was incorrect. A series of more
than 3 mix ratio alarms during the lining shall require the lining
to be aborted. Any out of specification readings shall be
highlighted on the rig printout and recorded on the relevant
documentation.
10.9.39
In this clause the first figure refers to standard PU lining of
pipes up to 300mm in diameter, the first figure in brackets
refers to standard PU lining of pipes equal to or greater than
300mm in diameter and the second figure in brackets refers
to semi-structural PU lining of pipes with a 3mm thickness.
10.9.40
Any reading of less than 0.80 (1.50) (2.80) mm shall be
highlighted on the rig printout, recorded on sheet NCR and
requires a pipe sample to be exhumed at the location where
the thickness was incorrect.
10.9.41
Any individual reading between 0.80 (1.50) (2.80) and 0.99
(1.49) (2.99) mm shall be highlighted on the rig printout and
recorded on the relevant documentation.
10.9.42
5 or more consecutive readings between 0.80 (1.30) (2.80)
and 0.99 (1.49) (2.99) mm shall be highlighted on the printout,
recorded on the relevant paperwork and requires a pipe
sample to be exhumed at the location where the thickness
was incorrect.
10.9.43
Any indication that the lining was consistently less than 1.0
(1.5) (3.0) mm shall be recorded on the relevant
documentation and will require overlining.
10.9.44
Should the rig printout fail and show no readings either for part
or all of the lining, details shall be recorded on the relevant
documentation and at least one pipe sample shall be
exhumed to confirm lining thickness.
10.9.45
Even if the reported mix ratio remains within specification, any
fluctuation that causes an alarm will require investigation as
the ratio at the lining application head may be unacceptable.
The course of action is to conduct post lining weight checks
and exhume a pipe sample at the location where the alarm
sounded.
10.9.46
The most common lining faults with minimum rectification
works are as follows, the Utility Representative shall
determine severity and requisite actions:
(i)Clause 10.9.39 to 10.9.46 relate to
the use of a water quality liner or semi
structural liner.
(ii)The structural enhancing liner
introduced in 2016 can range in
thickness from 2.75mm to 8.0mm. The
lining thickness is calculated using
length of main to be renovated, water
pressure and mains material. Lining
tolerances are agreed with the service
partner and a defect rectification date
agreed at the same time.
CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
FAULT
RECOMMENDED RECTIFICATION WORKS
Miss or exposed pipe
pipe sample exhumed at the relevant location
Slump
pipe sample exhumed at the location, if lining
less than 1mm on any part of the pipe the main
or affected pipe to be overlined
Minor water damage
depending on severity, pipe sample exhumed
at the location (little exposed pipe) to remove or
assess extent of severity or rectification
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Major water damage
Section 10 – Water Mains Renovation
pipe sample at location to remove or access
extent of (lining removed to severity for
rectification expose pipe)
Rings
pipe sample exhumed at location to assess
severity, if trough appears less than 1.0 (1.50
(3.0) mm shall be overlined
Unmixed or soft lining
pipe sample exhumed at the location to remove
and assess severity for rectification – possible
overline or replacement. (Rig should be
assessed by fitter before further use to
determine cause
Blister pipe
sample exhumed at the location if damaged or
broken. Otherwise severity to be assessed and
remedial works determined by Utility
Representative.
Blowholes
severity to be assessed and remedial works
determined by Utility Representative.
Obstruction in lining
if obstruction cannot be removed by swabbing,
pipe (skids, swabs, etc.) sample to be exhumed
at location
10.9.47
The Contractor shall slowly charge the renovated section with
water. When fully charged the joints shall be checked at full
static pressure to ensure that no visible leakage is present.
Any visible leakage shall be corrected by the Contractor
immediately. The Contractor shall ensure that customer
supplies have been properly restored and shall be responsible
for all work necessary to restore these supplies.
10.9.48
The Contractor shall supply all documentation relevant to
each lining to the Utility Representative within 24 hours of the
main being returned to service. Full and accurate completion
of this documentation is intended to ensure compliance with
the requirements of this specification.
10.9.49
The following sheets to the regulatory format defined in the
Water Industry Specification/Information and Guideline Notes
shall be provided for every lining:
1)
10.9.50
10.9.51
CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
Rapid-setting polymeric Lining Record (RSPLR) to
include a copy of the numerical rig printout and dip cards.
The following sheets to the regulatory format as defined in the
Water Industry Specification/Information and Guideline Notes
shall be provided when circumstances dictate:
1)
Non Conformance Record (NCR) – to report any defect
experienced during lining
2)
Pipe Sample Quality Record (PSQR) – for every pipe
sample exhumed
3)
Weight Check Calculation Record (WCCR)
4)
Spin up Determination Record (SUDR)
5)
CCTV Record Sheet (CCTVR)
All sheets shall be cross-referenced and signed by the
Contractor and the Utility Representative as a true and
accurate record of each lining. Such paperwork shall be
completed for test linings carried out above ground on new
iron pipes that are subsequently used as pipe make-up
pieces. The Utility Representative shall be informed of the
locations where such pipework is installed in the network.
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Yorkshire Water Services Ltd additional,
new or substitute clauses
Section 10 – Water Mains Renovation
10.10 (N)
SLIPLINING AND CLOSE FIT LINING
10.10.1
Sliplining is defined as the process whereby a lining pipe is
installed inside an existing parent pipe and the lining pipe is of
a smaller diameter than the parent and does not form an
interference with it.
10.10.2
A close fit lining is defined as one which after installation forms
a tight interference fit with the existing pipe. Initially it is
reduced in diameter either as a circular or deformed pipe prior
to installation.
10.10.3
PE100 polyethylene pipe minimum SDR17 meeting the
requirements of BS EN 12201 shall be used for Sliplining and
Closed-fit lining. For welded pipe the external bead shall be
removed prior to installation. It is envisaged that all operations
will be completed within a 10 hour shut-off period and that
every effort will be made to maintain customers’ supplies
during these operations.
10.10.4
The Contractor shall ensure that all installation works are
conducted as expeditiously as practicable. It is envisaged that
scheme design, planning and programming will be conducted
in a manner to maximise productivity and fully utilise resource
in the most cost effective manner whilst undertaking the work
with minimum disruption to customers and road-users.
10.10.5
The equipment to reduce the diameter of circular polyethylene
pipe in situ can be based on diametrically opposed
mechanical rollers or a reduction die (with or without heating
of the pipe and/or die). The number of rollers used or the
configuration of the die should be such that the pipe be
reduced in diameter by more than 10% of the original diameter
and any ovality introduced shall be no more than 2% in either
of two axes at right angles to each other.
10.10.6
The pipe shall be pushed or pulled through the equipment. For
swage lining or cold die drawn lining the maximum stress
exerted on the pipe shall not exceed 10MPa for PE100 and
the pipe shall be maintained in tension within the maximum
limits defined above, modified to suit actual diameter, wall
thickness and temperature conditions, until the installation is
complete from end to end.
10.10.7
Deformed linings shall be prepared with circular pipes which
can be deformed immediately after extrusion in the
manufacturing process. The pipe shall be collapsed and
folded and then coiled on a reel in an appropriate configuration
to suit the diameter and pressure rating of the pipe. This
procedure relates to pipes up to 315mm in diameter.
10.10.8
The manufacturing process shall be to the Approval of the
Project Manager.
10.10.9
For larger pipes it will be allowable to carry out in-situ
deformation of the pipe using suitable equipment. This should
be such that the pipe is pushed through a plough share
arrangement located in a semi-circular guide channel to
collapse and fold the pipe. The plough share shall be of a
design that does not damage the pipe and of sufficient length
so as to allow gradual deformation and folding of the pipe.
10.10.10
The use of a prescribed banding system to retain the pipe in
its deformed shape will be allowed.
10.10.11
Any requirement for the heating of the pipe in a site procedure
to carry out a reduction in size or allow entry into the existing
pipe shall be notified in the method statement to be submitted
with the tender together with details of the temperature and
the stage of the installation where such heating is
required.10.10.12
After adequate notification has been
given to the customers affected, the main to be lined shall be
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isolated by the operation of appropriate valves. In addition
stop taps shall have been located by the Contractor, their
operations checked, and any problems in their operation or
condition of their furniture reported as part of the detailed
design proposal. The Contractor will be responsible for
operating all stop taps prior to cleaning.
10.10.13
Cleaning of the pipe by an air vortex pipe cleaning technique,
is the recommended cleaning technique.
10.10.14
In addition the Contractor shall expose and remove all ferrule
connections from the main and shall cut suitable windows in
the wall of the host pipe to allow new service pipe connections
to be made.
10.10.15
CCTV survey and inspection shall be carried out prior to
installation of the lining to be installed. The passage of the
CCTV camera will be considered as being adequate proving
of the main.10.10.16 For Sliplining an adequate and
calibrated winch with a current test certificate provided by an
independent testing house must be used to install the pipe.
The winch shall be equipped with a tension limiting device
which can be set to ensure that the winch force imparted to
the pipe cannot exceed the maximum load of at least 1.5 times
the maximum possible tension generated by the winch.
10.10.17
The Contractor shall ensure that operatives and public are
protected from the winch wire at all times during winching
operations by suitable cages. In addition the public must be
prevented from obtaining access to excavations by the use of
secure barriers.
10.10.18
The winch shall be connected to the pipe lining, which shall
have been fitted with an appropriate nose cone for the pulling
operation, with a fully tilting swivel head.
10.10.19
The winch shall be adequately restrained such that all reaction
forces are contained within the excavation and do not induce
ground movement.
10.10.20
For close-fit linings the pipes shall be pulled or pushed through
rollers, die or deforming device at a speed which will ensure
that the required reduction can be achieved. The Contractor
shall monitor and carry out check measurements to confirm
this fact. For linings deformed in-situ some temporary
strapping may be applied to retain the deformation. For factory
deformed lining it is assumed that such strapping will have
been applied at the factory prior to the pipe being coiled.
10.10.21
The reduced diameter lining shall be immediately installed in
the existing pipe such that the installation is complete within a
natural inversion period where this is relevant.
10.10.22
The lining shall be installed beyond the existing pipe to
account for longitudinal recovery of the length as the result of
reversion to the original diameter. The Contractor shall
determine the required length necessary for recovery prior to
installation of the lining.
10.10.23
Where preliminary heating of a deformed pipeline on a coil is
necessary to allow initial insertion the method of achieving this
and control of lining temperature must be stated in the Tender.
On no account should the temperature of the lining be allowed
to exceed 70 degrees centigrade and the Contractor shall
supply thermocouples or some other method to monitor the
temperature of the pipe on the coil.
10.10.24
In all cases the pipe must enter the pipeline through a properly
configured trench and pulley arrangement.
10.10.25
If air/water pressure is to be used for reversion care must be
taken to charge the main and slowly increase its pressure to
the appropriate value. Under no circumstances will reversion
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pressures, which should be stated in the method statement,
be allowed to exceed 80% of the manufacturer’s specified
yield stress of the pipe. Appropriate calibrated recording
gauges shall be provided and fitted such that a continuous
record of the pressure profile over the necessary period of
time may be kept.
10.10.26
Where reversion takes place under pressure the ends of the
deformed pipes shall be locally heated to fully revert a short
length of pipe to the full diameter and allow fixing of a suitable
fitting and flange for filling and pressure monitoring.
10.10.27
Such reversion may require the use of a steam/air mixture and
suitable measures, that may require the use of thermocouples
which shall be used to monitor the temperature of the lining
throughout its length. Injection of steam shall be carried out
along the length of the lining such that an even distribution of
temperature is achieved with no section at a temperature
greater than 125 degrees centigrade. The output from the
thermocouples or other adopted monitoring method shall
provide a continuous temperature record that shall be logged,
and a copy provided to the Project Manager’s Representative.
10.10.28
If natural reversion is adopted the lining shall be left for a
sufficient period to ensure that the full reversion occurs. The
Contractor shall determine the minimum periods necessary
for pipes of various diameter and pressure classification.
10.10.29
Once the reversion process is complete the lining shall be
allowed to cool or water drained away to allow for piecing up
and the fittings of service pipe connections. No piecing up or
ferrule connection shall take place until full longitudinal
recovery of the pipe has been achieved.
10.10.30
In the case of PE100 lining pipe an annular section of host
pipe may be removed to facilitate electrofusion ferrule
connection. This should be carried out in advance of the lining
installation and all sharp edges on the cut face shall be
chamfered so as not to impart damage to the installed pipe.
Any oversized gaps between oversized sections of host pipe
and the lining shall be grouted.
10.10.31
Renewal of ferrule connections shall be made using an
electro-fusion welded fitting supplied with a suitable strapping
arrangement to retain the fitting to the lining during the welding
operation. No automatic renewal of the communication pipe
between the ferrule and the stop tap box will take place unless
the condition of the pipe warrants such replacement. Such a
situation will arise where the communication pipe is lead and
there is a history of burst/leakage.
(i)
Lead service pipes are
lined using an adapted vortex
cleaning technology or replaced.
(ii)
The in-situ lining of service
pipes shall be carried out in
accordance with YW Method
Statement on Cleaning and Lining of
Lead Service Pipes, the ‘Code of
Practice: In-situ Resin Linings of
Water Mains (IGN 4-02-02) and the
Operational Requirements: In-situ
Resin Lining of Water Mains (WIS 402-01), published by Water UK.
Any Electrofusion box used shall comply with Clause 2.97.7.
10.10.32
Thin walled closed fit lining may be acceptable to the Project
Manager and details of any such proposals shall be submitted
by the Contractor with a method statement. The method
statement will address all aspects with respect to type of
materials and method of installation in particular measures to
fix ferrules or service connections to the lining as well as
termination and connection details at the end of linings.
10.10.33
Details of the close-fit method to be adopted and the type of
ferrule and end sealing or connection mechanism to be used
shall be submitted for the Project Manager’s approval.
Couplings or adaptors to be used to connect close fit linings
with existing or new pipelines shall be of a type to provide a
seal against the parent pipe and the lining as well as providing
shear resistance and full end loading – liner grip or similar will
be an acceptable form of connection.
10.10.34
Use of existing pipework or fittings to resist forces generated
by thrust or thermal movement is not permitted. Any
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Section 10 – Water Mains Renovation
mechanical connections must be capable of full end loading
and must have WRAS and CPP approval for use in contact
with potable water.
10.10.35
All make up pieces in excavations etc. must be completed with
10 bar rated PE pressure pipe or DI pipe.
10.10.36
The main shall be chlorinated in accordance with the
requirements of clauses 7.11.10.10.37 The Contractor shall
slowly charge the renovated section with water. When fully
charged the joints shall be checked at full static pressure to
ensure that no visible leakage is present. Any visible leakage
shall be corrected by the Contractor immediately. The
Contractor shall ensure that customer supplies have been
properly restored and shall be responsible for all work
necessary to restore those supplies.
10.10.38
The Contractor shall undertake inspections and maintain the
following records contemporary with their sliplining activities
for each lining length. The records shall be produced to an
agreed format, copies of which will be signed by the
Contractor and supplied to the Project Manager. The
Contractor shall submit for approval a record form by the
Project Manager. The records shall be maintained to enable
the quality of the works to be audited at any time and shall
include:
1)
Date of work
2)
Pit references between which lining pipe is installed and
location description.
3)
Length of main lined
4)
Gang reference
5)
Size and material of existing pipe
6)
Maximum and minimum recorded internal diameter of
existing pipe
7)
Cleaning method used and extent of each where
appropriate
8)
Results of post cleaning CCTV inspection and video
reference
9)
Size of any gauging pig
10) Details of lining pipe at pipe entry, intermediate position
and on completion
11) Temperature of lining pipe at installation
12) Pulling force on lining pipe at pipe entry, intermediate
position and on completion
13) Number of service connections
14) Scoring or surface damage to lining pipe
15) Client water sample reference number
16) Details of obstructions removed or non-conformance
reference (if applicable)
17) Signature of Contractor’s Representative to confirm
accuracy of preceding records
18) Authorisation for commissioning of mains by Project
Manager’s Representative
19) Time and date of supply restorations
10.10.39
All the records other than numbers 17 to 19 must be
completed by the Contractor and inspected by the Project
Manager’s Representative prior to authorisation to bring the
main in to service.
10.10.40
If at any time before, during or after installation scoring of the
lining pipe occurs exceeding 10% of the original lining pipe
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wall thickness, the Contractor shall record his actions in
identifying the extent of such scoring and the remedial works
undertaken to remove the defective length.
10.11 (N)
AIR SCOURING
10.11.1
Air scouring operations are for the removal of loose deposits
only on mains up to 8 inch diameter and it is not intended that
hard tuberculation should be capable of being removed by this
process. The Contractor’s proposal for air scouring should
reflect this requirement. All work shall be carried out in
accordance with the recommendations contained in
‘Removing Loose Deposits from Water Mains: Operational
Guidelines’ by WRC.
10.11.2
It is envisaged that these operations will be completed within
a 10 hour shutdown period. The Contractor shall inform the
Project Manager at the detailed design proposal whether or
not such a timescale is applicable. If during construction it is
apparent that such a timescale will not be achieved the
process will be stopped and the Contractor shall provide
suitable personnel to restore customer supplies within the
warning period.
10.11.3
The Contractor shall ensure that all installation works are
conducted as expeditiously as practicable. It is envisaged that
scheme design, planning and programming will be conducted
in a manner to maximise productivity and fully utilise resource
in the most cost effective manner while minimising disruption
to customers and road-users. The Contractor is expected to
continually review all operations with a view to consistently
improve the entire rehabilitation process, the development
and implementation of novel programming regimes will be
expected by the Project Manager.
10.11.4
The Contractor shall plan their operations such that entry
points can be used for multiple air scouring operations
wherever possible in order to minimise excavations. Wherever
it is possible existing hydrants and valves shall be used for
carrying out this cleaning technique.
10.11.5
The Contractor shall submit to the Project Manager as part of
the detailed design proposals, details of enabling works, air
injection and discharge points, valve operations and cleaning
sequence.
10.11.6
The Contractor shall make arrangements to separate
suspended matter from the water discharged from the mains
being cleaned by use of settlement tanks or lagoons. The
settlement tanks shall comply with Clause 10.9.23. The
Contractor shall be responsible for obtaining the necessary
permission for siting of lagoons and arrangements for
discharge of effluent from lagoons or settlement tanks. Any
discharge of water to a piped sewerage system or
watercourse must be in accordance with procedures
confirmed by the written agreement of the Sewerage
Undertaker or the Environment Agency.
10.11.7
The air scouring equipment shall be such that if separate units
are used, comprising air compressor, air coolers, filter and
control unit they cannot be connected incorrectly.
10.11.8
All equipment shall be in good mechanical condition. The
compressor shall release as little oil as possible in to the air
stream. Filters shall be installed to remove oil or other
contaminants and filter elements shall be replaced at regular
intervals in accordance with the manufacturer’s instructions.
10.11.9
The efficiency of the air filter unit shall be tested by the
Contractor. The air filtered unit should produce filtered air
which does not impart a detectable odour or taste when about
50 litres of air is bubbled through 1 litre of water. This test shall
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be carried out before the commencement of each day’s
cleaning activity and be documented by the Contractor.
Equipment that does not meet this test shall not be used for
cleaning.
10.11.10
All branch lines, including customer stop taps shall be closed
during cleaning operations to prevent discoloured water being
carried through the distribution system.
10.11.11
The duration of air scouring in a section of main shall continue
until clear water conditions appear at the point of discharge.
10.11.12
All works related to the maintenance or replacement of stop
taps and installation of new fittings identified by the Contractor
during detailed design and incorporated on the construction
drawings shall be carried out in advance of the cleaning
operations.
10.11.13
The Contractor will be responsible for closing all stop taps
prior to cleaning and opening to restore supply upon
completion of the works.10.11.14
Unless
otherwise
directed existing mains cleaned by air scouring may be
returned to service without disinfection.10.11.15 The
Contractor shall slowly charge the renovated section with
water. The Contractor shall ensure that customer supplies
have been properly restored and shall be responsible for all
work necessary to restore those supplies.
10.12 (N)
LINERS TO PIPES IN DAMS
10.12.1
The structural or semi structural lining requirements shall be
as specified in the Works Information or as directed by a
suitably qualified Chartered Civil Engineer approved by the
Employer.
10.12.2
Use of HDPE or MDPE pipe.
a)
All pipes shall be butt welded to the full required length
prior to insertion. Any proposal to line the pipe with
shorter lengths shall be approved by the Employer
b)
All welding beads shall be removed prior to insertion.
10.12.3
All lining pipes shall be designed to be as large a diameter as
possible to give a tight fit within the host pipe.
10.12.4
Pressure Testing shall be carried out in accordance with
Section 7 Testing and Disinfection of this specification. A
minimum Test Pressure of 1.5 times the static head shall be
used in all circumstances.
10.12.5
All lining pipes shall be centrally located within the host pipe
using lugs or spacers.
10.12.6
All liners shall have a welded flange on the upstream end of
the pipe and shall be bolted to the control valve or penstock
or secured in any such other manor as approved by the
Employer.
10.12.7
The annulus of the liner shall be grouted in accordance with
Section 9.8 Annulus Grouting Generally, using a non-shrink
grout.
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Section 11 – Tunnelling and Shaft Sinking Works
SECTION 11
TUNNELLING AND SHAFT SINKING WORKS
The Notes for Guidance are not part of
the Specification.
11.1 HEADINGS, TUNNELS AND SHAFTS
(i) For further guidance, see British
Tunnelling Society and Institution of Civil
Engineers ‘Specification for Tunnelling’.
(ii) Where appropriate, particularly in
areas of previous mining activity,
probing ahead requirements should be
described in the Contract.
(iii) This Section, as well as dealing with
tunnelling and shaft sinking, provides for
thrust boring.
(iv) The need for any ground
investigation ahead of the face of any
tunnel, heading or shaft should be
described in the Contract.
Yorkshire Water Services Ltd additional,
new or substitute clauses
1. Any restrictions on vehicle movements and working hours shall be as
stated in the Contract.
2. On Site storage capacity required for excavated materials shall be stated
in the Contract.
3. Excavations for headings and tunnels shall be adequately supported at all
times. The faces of all headings and tunnels, other than those in solid rock,
shall be fully supported whenever excavation has been stopped for a period
exceeding 12 hours.
4. All working shafts shall be supplied with effective means of communication
with the Works below ground. A fail-safe back-up means of communication
shall also be provided.
11.1.5 (A)
Unless otherwise specified the requirements of the
“Specification for Tunnelling”, published by the British
Tunnelling Society and the Institution of Civil Engineers shall
apply.
11.2 SHAFTS
(i) Any special requirements relating to
protection should be described in the
Contract.
(ii) Special Clauses will be required for
other types of shaft sinking.
1. A safe means of access and egress shall be provided in compliance with
BS 6164. All shafts shall be provided with a primary and secondary means
of access and egress. A ladder access shall be provided in addition to any
mechanical means.
2. Segments used in shafts shall be so erected as to break vertical joints,
except in any rings required to be broken out.
3. Where shafts are constructed by underpinning and lined with segments,
they shall be grouted up at least once per shift.
4. Where segmental shafts are sunk by caisson methods, an annulus shall
be maintained by a lubricant which shall be replaced with a grout on
completion.
5. After any primary lining is complete and before any openings are made at
or near the foot, the excavation for the base of the shaft shall be taken out
and the base concreted.
Yorkshire Water Services Ltd additional,
new or substitute clauses
11.2.1 (S)
A safe means of access and egress shall be provided in
compliance with BS 6164. The provision of primary and
secondary means of access and egress routes shall be subject
to a risk assessment and shall be agreed with the Employer. A
ladder access shall be provided in addition to any mechanical
means.
11.3 OPENINGS IN SHAFTS AND TUNNELS
(i) The Contract should describe any
limitations which the design of the tunnel
CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
1. Drawings shall be provided showing proposals for forming openings in
shafts and tunnels. These Drawings shall include details of temporary
supports to the lining and to the ground.
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or shaft will impose on temporary
openings.
Section 11 – Tunnelling and Shaft Sinking Works
2. Openings in shafts and tunnels shall only be made after the segments
have been grouted.
11.4 SEGMENTAL SHAFT AND TUNNEL LININGS
1. Segments shall be erected and assembled in accordance with the
manufacturer’s instructions and the Contractor’s method statement. The
lining shall be built as soon as possible after the ground has been cut.
11.5 UNBOLTED CONCRETE TUNNEL SEGMENTS
(i) Requirements for any circumferential
pre-stress should be described in the
Contract.
1. The shape of unbolted concrete segmental tunnels shall be maintained
within tolerance after erection, until the segments have been stabilised by
grout or other means.
2. Where a circumferential pre-stress is applied, the force shall be such that
the whole of the concrete lining is expanded tight against the surrounding
ground. A joint lubricating compound shall be applied to all wedge faces of
each segment to be expanded.
3. Where wedge block segments are specified, the excavated profile shall
be lubricated to reduce skin friction.
4. Where key segments are shorter than other segments comprising the ring,
the pockets formed shall be filled with concrete to the grade specified in the
Contract.
11.6 BOLTED CONCRETE SEGMENTAL LININGS
(i) Any requirement relating to rolling of
segments should be described in the
Contract.
1. Segmental joints to bolted concrete tunnel and shaft linings shall be trued
and longitudinal joint bolts tightened before the final tightening of the
circumferential joint bolts connecting the ring to the adjacent ring.
2. Packings shall be inserted in the joints of the lining at the time of erection,
as required, to maintain correct shape, line and level, and shall not exceed
6 mm or half of the sealing capacity of the gasket.
3. Segments shall be fixed in accordance with manufacturer’s
recommendations. Where grummets are to be used, two grummets shall be
threaded on each bolt to be grummetted at the time any bolted segment is
erected. One grummet shall be placed under the washer at the head of the
bolt and the other under the washer at the nut.
11.7 GROUTING OF SEGMENTS
(i) Any requirements for high pressure
grouting should be described in the
Contract.
(ii) Any locations where it is required to
grout more frequently than once per shift
should be described in the Contract.
(iii) When selecting grout, due regard
should be given to its specification to
ensure that local aquifers are not
polluted.
1. Segmental shaft and tunnel linings shall be grouted by forcing the required
grout through the grouting holes in the segments, so that all interstices
around the outside of the segments are filled. Adequate venting shall be
provided to ensure that air is not trapped.
2. Temporary hardwood plugs shall be inserted into grout holes after
grouting; these shall be replaced by permanent plugs of material similar to
that of the segments being grouted when it is evident to the Client that
grouting has been effective.
3. Grout pipes shall be provided in head walls or ring walls, and any void
remaining after concreting shall be filled with the required grout.
(iv) A pressure gauge should be fitted
onto the grouting nozzle to avoid ground
heave, overstress or distortion.
4. Where primary grouting does not completely fill all cavities, secondary
grouting shall be carried out.
Yorkshire Water Services Ltd additional,
new or substitute clauses
11.7.6 (A)
CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
5. Grouting shall closely follow the erection of rings, be undertaken every
four rings, and at least twice per shift.
If circumstances require a thixotropic grout should be used
instead of the standard G1 grout. Proprietary grout may be
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Section 11 – Tunnelling and Shaft Sinking Works
chosen and used in accordance with the manufacturers’
instructions.
11.8 CAULKING
(i) Material to be used for caulking
should be described in the Contract.
(ii) The time when caulking is carried out
may depend, for example, upon ground
conditions and availability of the working
area.
1. Caulking of segment joints in tunnels and shafts shall be carried out as
late as practicable within the construction programme; the grooves shall be
raked out and cleaned immediately before caulking.
2. Caulking of circumferential and longitudinal joints shall be bonded to form
a homogeneous and continuous mass, consolidated to fill the recess up to
the inner surface of the segment or to the depths described in the Contract.
11.9 POINTING OF JOINTS
1. Where joints between segments are required to be pointed, they shall be
raked out, cleaned, filled with a proprietary non-shrink cement mortar and
pointed flush.
11.10 SECONDARY LININGS TO SEGMENTS
(i) The specification of the lining and the
surface finish should be stated in the
Contract.
1. Before construction of a secondary internal lining to a segmental tunnel is
commenced, it shall be cleaned out, caulked and proven to be watertight.
2. The minimum thickness of lining over the ribs of the segments shall be
agreed in advance with the Client, unless otherwise stated in the Contract.
11.11 WATERTIGHTNESS OF SHAFTS AND TUNNELS
(i) See also Clause 7.8.
1. Shafts and tunnels shall be substantially watertight, with no identifiable
flow of water penetrating either the primary or secondary lining.
11.12 CONTROL OF GROUNDWATER
1. Working methods and systems shall be designed to control groundwater
and, where necessary, to remove water from the tunnel. Removal of
groundwater shall not cause damage to the Works nor to the property of third
parties.
11.13 PIPE JACKING
(i) Advice on the design and construction
of pipejacks is given in ‘A Guide to Best
Practice for the Installation of Pipejacks
and Microtunnels’, published by the Pipe
Jacking Association.
(ii) Collars fabricated from weldable
structural steel may be susceptible to
corrosion from the ground, groundwater
or the effluent carried. If corrosion can be
expected, the design of the joint should
provide for a secondary sealing gasket
to be applied on Site.
(iii) The material required to seal the
joints should be described in the
Contract.
1. Excavation for pipe jacking shall be undertaken from within a shield
equipped with steering jacks for adjusting the alignment. Face boards shall
be available for boarding up the exposed excavation.
2. The jacking load applied to the pipeline shall be limited so that damage to
the pipes is avoided and an intermediate jacking station shall be provided,
where necessary, to achieve this.
3. The jacking load shall be transferred to the pipes through a thrust ring,
which shall be sufficiently rigid to ensure even distribution of the load.
4. The pipe manufacturer’s permitted draw or angular deflection shall not be
exceeded at any individual joint.
5. Up-to-date records shall be maintained of jacking loads and line and level
measurements. A graphical relationship between the jacking force and the
distance moved shall be produced to ensure that the necessary measures
are taken to avoid exceeding the maximum permitted jacking forces.
6. All lifting holes and grouting holes shall be sealed.
7. Joint packing material designed to distribute the jacking load evenly shall
be inserted at, and between, the pipe ends, and at any intermediate jacking
stations.
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8. Before work may start on any thrust pit, it shall be demonstrated that the
design will withstand the maximum jacking force of which the jacks are
capable.
9. Before a particular pipe jack may commence, evidence shall be provided
that the pipes necessary for completing the jack are on Site or in storage
elsewhere. The envisaged number of intermediate jacking stations shall be
agreed in advance of commencement. At least one intermediate jacking
station assembly shall be available at the start of the pipe jack, unless
otherwise agreed.
10. Pipes, including lead pipes, which have been jacked through a pipe jack
shall not be used elsewhere on the Works. Cut pipes shall not be jacked.
11. Pipe jacking shall be undertaken in a continuous operation and the
jacking load shall be limited so that installed joints are prevented from
opening when the jacking loads are removed.
12. On completion of the drive, intermediate jacking stations shall be left fully
closed. All jacks, props, thrust rings and packing shall be removed, the ends
of the pipes cleaned, a new packing ring glued to the receiving face and the
joint jacked partly closed. An “O” ring seal shall then be inserted into the
sliding joint and the joint jacked fully closed. The order of closing the stations
shall be from the tunnelling shield working back.
13. The annular space between the sides of the excavated tunnel and the
jacking pipes shall be constantly filled with an approved lubricant at a
pressure that will support the adjacent excavation. Daily records of the
quantity of lubricant used for each length of pipe thrust and the point at which
the lubricant was injected shall be submitted to the Client. The lubricant shall
be thoroughly mixed prior to pumping or placing. On completion of the pipe
jack, the annulus shall be filled by displacing the lubricant with grout.
Yorkshire Water Services Ltd additional,
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11.13.14 (A)
Unless otherwise specified the guidance given in “A Guide to
Best Practice for the Installation of Pipejacks and
Microtunnels” published by the Pipe Jacking Association shall
be followed.
11.14 MICROTUNNELLING
1. The microtunnelling machine shall be selected with regard to the ground
conditions, length of drive and other relevant factors.
2. Microtunnelling shall comply, generally, with the provisions of Clause
11.13.
11.15 VENTILATION OF TUNNELS AND SHAFTS
(i) See also the ‘Construction (Health,
Safety and Welfare) Regulations’, 1996,
the ‘Construction (Health, Safety and
Welfare) Regulations’ (Northern Ireland)
1996, BS 6164 and HSE Guidance Note
EH40.
1. Sufficient ventilation throughout the tunnels and shafts shall be provided
to ensure that a safe working environment is maintained at all times.
11.16 WORK IN COMPRESSED AIR
(i) The ‘Work in Compressed Air
Regulations’, 1996, (and the ‘Work in
Compressed Air Regulations (Northern
Ireland)’, 2004) and the accompanying
Guidance Notes should be referred to
when carrying out work in compressed
air.
CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
1. Full details shall be submitted to the Client of the type, capacity and
arrangement of the compressed air plant, ancillary equipment and medical
facilities it is proposed to install.
2. All standby plant shall be tested weekly by using it to supply air to the
Works under normal working conditions.
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(ii) The CIRIA Report R44 gives
recommendations as to standards of
good practice for work in compressed
air.
Section 11 – Tunnelling and Shaft Sinking Works
3. After installation, but before work in compressed air is commenced, all
compressed air plant shall be given a 24-hour continuous running test at the
normal operating pressure.
(iii) The appropriate provision of BS 6164
also applies.
11.17 RECORDING OF INFORMATION
1. Records shall be kept of the line, level and the diameter, measured
horizontally and vertically, of any tunnel lining. Similar records shall be kept
for shafts and for pipe jacking.
11.18 TOLERANCES FOR SHAFTS, TUNNELS AND PIPE JACKS
(i) Where a tunnel is to have a secondary
lining, it may be necessary to specify
permissible deviations for the primary
lining, having regard to the nature of the
work.
(ii) Any requirements for more stringent
tolerances should be described in the
Contract.
(iii) Where a shaft or tunnel is to be
constructed in ground which is variable
or unstable, it may be appropriate for a
larger tolerance for line and level to be
described in the Contract.
1. The position of the internal face of any shaft or tunnel shall not deviate
from that described in the Contract by more than the following permissible
tolerances:
Work Category
Pipe jacking/
Microtunnelling
Shafts and chambers
Shafts and tunnels
Tunnels without
secondary lining
Tunnels with
secondary lining
Shaft, tunnel and
sewer lining segments
Dimension or
Alignment
Permissible
Tolerances
Line
± 50 mm
Level
± 35 mm
Vertically
1 in 300
Finished diameter
1% but not exceeding
± 50 mm
Line
± 35 mm
Level
± 35 mm
Line
± 35 mm
Level
± 35 mm
Maximum lipping
between edges of
adjacent segments
10 mm
2. The difference between maximum and minimum measured diameters in
any one segmental ring shall not exceed 2% of the diameter of the ring.
3. No combination of tolerances resulting in a reverse fall will be permitted
where the invert of the tunnel is required to convey sewage by gravity flow.
CDIMS ASS IMP ENG SP H 0302 A1.A01-V20
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