Water Services Training Group
14th Annual Conference
New Decade – New Challenges
9th September 2010
New Decade - New Challenges
Annual Conference September 2010
Trenchless Watermain
Rehabilitation Techniques
Padraic J Fogarty
Director
New Decade - New Challenges
Annual Conference September 2010
Outline of Presentation
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Introduction
Rehabilitation Techniques
Review of Rehabilitation Techniques
Other Issues
Conclusions
New Decade - New Challenges
Annual Conference September 2010
Introduction
New Decade - New Challenges
Annual Conference September 2010
The Good News
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Water Services Investment Programme
(WSIP) 2010 to 2012
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Contracts with a total value of €321 million
to commence construction in the period
2010 to 2012.
90% Funding
WSIP 2010-2012 the Start!
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Annual Conference September 2010
Mains Rehabilitation Strategy
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Starting Point
Identifies
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Mains for Rehabilitation
Reasons for Rehabilitation
Pipe Materials
New Decade - New Challenges
Annual Conference September 2010
Objectives
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Bang for Buck (More for Less)
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Quality Installation
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Water Quality - Drinking Water Regulations - “Protect Human
Health"
Watertightness - Reducing UFW
Robust and Durable Installation
Minimise Impact
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Selection of Mains
Selection of Techniques
Interruption to Supply
Traffic and Access
Environmental – drilling fluids etc.
Nuisance - dust, noise etc.
Sustainable Construction
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Annual Conference September 2010
Terms and Abbreviations
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Rehabilitation –
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Replacement –
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All methods for restoring or upgrading the performance of an
existing pipeline system
Methods of rehabilitation of an existing pipeline system by the
installation of a new system, either on or off the existing line,
without incorporating the original fabric
Host Pipe – Existing pipe/mains to be rehabilitated
Spray in Place Pipe (SIPP)
Cured in Place Pipe (CIPP)
Horizontal Directional Drilling (HDD)
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Annual Conference September 2010
Rehabilitation Techniques
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Annual Conference September 2010
Slide with photo or graph
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Annual Conference September 2010
Structural Rehabilitation
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Cured in Place Pipe (CIPP)
Close Fit Sliplining
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Diameter Reduction
Rolldown
Sliplining
Pipe Bursting/Pipe Splitting
Horizontal Directional Drilling
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Annual Conference September 2010
Non Structural & Semi Structural
Rehabilitation
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Internal Joint Seals
Spray in Place Pipe (SIPP)
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Cement Mortar Lining
Epoxy Lining
Cured in Place Pipe (CIPP)
Close Fit Sliplining
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Diameter Reduction
Rolldown
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Annual Conference September 2010
Spray in Place Pipe - Epoxy
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Thorough
cleaning of host
pipe
Spray host pipe
with a thin lining
of resin (typically
1mm thick)
 Advantages:
Minimal excavation
 Disadvantage: Requires a completely clean
and dry host pipe
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Annual Conference September 2010
Cured in Place Pipe
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Fabric tube impregnated
with thermosetting resin
Inserted in host pipe and
heat cured – 2 Methods
 Pulled into host pipe
and expanded by
water pressure
 Liner turned inside
out (Inversion)
 Advantages:
Service connections
can be reinstated by robotic cutters
 Disadvantage: Requires extensive
pre-investigation
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Close Fit Sliplining – Diameter
Reduction
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New pipe temporarily
deformed
Two methods
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Swaging
Compression Rollers
 Advantages:
Limited loss of pipe diameter
 Disadvantage: Difficult to install if irregularities in host
pipe
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Annual Conference September 2010
Close Fit Sliplining – Rolldown
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Liner is heated
and folded
Liner is winched
into host pipe
and reshaped by
heat and
pressure
 Advantages:
Limited loss of pipe diameter and
accommodates bends
 Disadvantage: Reversion process may be difficult
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Annual Conference September 2010
Sliplining
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HPPE pipe is
pulled into host
pipe
 Advantages:
Not reliant on integrity of host pipe
 Disadvantages: Reduction in pipe diameter (but
maybe not in capacity)
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Annual Conference September 2010
Pipe Bursting/Pipe Splitting
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HPPE pipe is
attached to
bursting head
Break and
displace host
pipe
Pull replacement
pipe into the void
 Advantages:
No cleaning required; facilitates upsizing
 Disadvantage: Difficult in some situations; not suitable
for Asbestos Cement mains
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Pipe Bursting - Execution
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Horizontal Directional Drilling
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Pilot bore to line
and grade
Reamer and new
HPPE pipe
pulled through in
reverse direction
 Advantages:
Less disruption compared to open cut;
existing supplies not cut-off
 Disadvantage: Depends on suitable soil conditions
and corridor free from existing services
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Annual Conference September 2010
Review of Rehabilitation
Techniques
New Decade - New Challenges
Annual Conference September 2010
Selecting Appropriate Technique (1)
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Flow Chart for Selecting the Rehabilitation
Technology
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Scale of Contract
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Replacement/Structural Rehabilitation
Non-Structural and Semi Structural Rehabilitation
Is it large enough to justify use of specialist
equipment?
Availability of specialist contractors and
equipment or option for knowledge transfer to
local contractors
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Selecting Appropriate Technique (2)
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Suitability of materials
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Suitability for contact with water
Physical properties (expansion and contraction)
Density of connections
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If more than 20 connections per 100m it may be
more economical to open cut
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Sustainable Construction
Open Cut
Directional
Drilling
Other No
Dig
Carbon Footprint
C
B
A
Waste
C
B
A
Local & Sustainable
Materials
C
B
B
Ecology
C
B
A
Archaeology
C
B/C
A
Health & Safety
B
A
A
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Annual Conference September 2010
Main Options
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Pipe Bursting
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Horizontal Directional Drilling
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Dependent on suitable site conditions
Rural/Semi Urban
Independent of Connections
Cured in Place Pipe?
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Annual Conference September 2010
Case Study: Arva, Co.Cavan
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Contract Details:
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Start Date: 8th June, 2010
Contract Period: 15 weeks
Scope of Works
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0.8km directional drilling of 180mm
HPPE
4.2km pipe bursting of 125mm HPPE
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Host pipe: 4" Cast Iron
New meter boxes on all connections
Replacement of lead services to
property boundary
Key Enabling Works
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Alternative Supply to facilitate pipe
bursting
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Other Issues
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Annual Conference September 2010
Form of Contract
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Capital Works Management Framework
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Public Works Contract for Civil Engineering
Works Designed by the Employer
Public Works Contract for Civil Engineering
Works Designed by the Contractor
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Standards for Products/Materials
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Two Aspects
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Strength and Robustness
Suitability for contact with Drinking Water
Products/Materials
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Pipes/Liners/Coatings
Valves and Fittings
Service Pipes and Fittings
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Rehabilitation of AC Mains
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Elephant in the Room
EPA Response to Pipe Bursting
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Not a feasible option
Options
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Cured in Place Pipe
Close Fit Sliplining
Offline Replacement Pipe
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Dealing with Existing Pipe?
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Annual Conference September 2010
Records and Monitoring
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Requirements of Appendix 7 of L6/07
UFW Reduction
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Prior to Rehabilitation
Post Rehabilitation
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Maybe no reduction in UFW initially due to
increased pressure
Robust GIS system and procedures:
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New infrastructure
Decommissioned infrastructure
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Annual Conference September 2010
Opportunistic Works
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Meter Boxes?
Lead Services?
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Annual Conference September 2010
Advancing Rehab Implementation
WSAs and Consultants
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Adoption of Mains Rehabilitation Strategy
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Identification of Contracts
Setting Requirements
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Contractor Qualifications
Performance Specifications
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Strategy for Rehabilitation of AC Mains
 Advancing Rehabilitation Contracts
 Resource and Training Needs
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Site Supervisory Staff
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Annual Conference September 2010
Advancing Rehab Implementation
Contractors
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Provision of Market Information
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Overall Programme – WSIP 2010 to 2012
Roll out of Contracts
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Contract Size
Design by Employer or Contractor
Rehabilitation Techniques
Reasons
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Efficient & Effective Implementation by facilitating
Contractors in identifying
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Plant Requirements
Resource and Training Needs
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Annual Conference September 2010
Conclusions
New Decade - New Challenges
Annual Conference September 2010
Key Success Factors
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Information
Technique to match Specific Circumstances
Competent Contractor
Preplanning
Response to Unknowns
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Contractor
Employer/Engineer
Engagement with Consumers
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Annual Conference September 2010
Conclusions
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Exciting New Phase in the Management of
Water Infrastructure Assets
 Evolving Situation
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Technology and Materials
Contractor Experience
Testing in Ireland
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Ground Conditions
Range of Contractors meeting Suitability Criteria
The Challenge 
Leave a Better Water Network Infrastructure for the
Next Generation
New Decade - New Challenges
Annual Conference September 2010
Acknowledgements
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Colleagues at TOBIN and Mouchel
Joe Doyle, USA Ltd and USSR Ltd.
Michael Ward, Ward & Burke
Construction Ltd.
New Decade - New Challenges
Annual Conference September 2010