Hertfordshire Highways
Process:
Develop and Deploy Policies, Plans and Strategies
Title:
Winter Service Operational Plan
Mandatory
Generic
Contract Specific
Guidance
Process
1
UNCONTROLLED IF COPIED or
PRINTED
AmeyLafarge
WINTER SERVICE OPERATIONAL PLAN
Contract:
Highway Works Contract (Hertfordshire)
Plan No:
HERTS-WINTERPlan-001
AmeyLafarge Statement of Intent
AmeyLafarge are the principal contractor for Hertfordshire County Council. AmeyLafarge is a
Joint Venture between Amey Infrastructure Services and Lafarge Aggregates Ltd.
Hertfordshire County Council, AmeyLafarge and Mouchel Parkman together form Hertfordshire
Highways.
Amey Lafarge have adopted Amey Infrastructure Services' Management Systems' for Quality
Assurance, Environmental and Health and Safety Management as the tool for Managing the
joint venture business and all operations it undertakes.
Purpose:
This Winter Service Operational Plan is a statement of intent to ensure that the management
of the Contract delivers the Client’s requirements and those of BS EN ISO 9001:2000. It is a
unique working document to provide guidance and direction for the effective management of
the winter maintenance service for the above Contract.
The Winter Service Operational Plan identifies those practices, resources, activities, controls
and procedures to be used on the Highways Works Contract to deliver customer satisfaction
and comply with the corporate management system.
Agreed by:
.....................................................................................
Date: .........................
Hertfordshire County Council
Agreed by:
.....................................................................................
Date: .........................
AmeyLafarge Project Director
Approved by: ......................................................................................
Date: .........................
AmeyLafarge Performance & Quality Manager
Approved:
A Shah-Cundy Authorised:
UNCONTROLLED if copied or printed
S Nicholls
© AmeyLafarge
Ref:
Rev:
HERTS-WINTERPlan-001
05
Date: Sep 05
Page 1 of 35
Hertfordshire Highways
Process:
Develop and Deploy Policies, Plans and Strategies
Title:
Winter Service Operational Plan
Mandatory
Generic
Contract Specific
Guidance
Process
1
RECORD OF REVIEW / REVISIONS
This management plan shall be reviewed during the summer period (between winter maintenance
periods) and updated accordingly. The reviews, including nil returns, shall be noted below.
Date
Oct-02
May-03
June03
Aug-03
Sept 04
Sept 05
Topic of Change
Approved
First Review
(not released)
General Review for discussion
(not released)
Improved format and updated
names.
Summer 2004 revision
Summer 2005 revision
Section(s)
Changed
All
All
Rev No.
00
01
Approved
BG
Draft only
Agreed
CP / SH
Draft only
All
02
Draft only
Draft only
All
03
BG
CP / SH
All
3,7,8,
App D
04
05
KK
ASC
SN
SN
REGISTER OF CONTROLLED COPIES
1
2
3
4
5
6
7
8
9
10
11
12
13
14
Holder
Performance &
Quality Manager
Antelope House
Coreys Mill
Rotunda
Hoe Lane
Trident
South Mimms
Shire House
Kings Langley
Shared Drive
Shared Drive
Shared Drive
Shared Drive
Shared Drive
Shared Drive
Company /
Organisation
AmeyLafarge
Location
Master copy on
site intranet /
network shared
drive
Policy Statements
& Management
Plans Folder
AmeyLafarge
Herts CC
Herts CC
Herts CC
Herts CC
Herts CC
Herts CC
Approved:
A Shah-Cundy Authorised:
UNCONTROLLED if copied or printed
Rev & Date of First
Issue
Rev 05
Copy
No
N/A
05 / Sept 05
Highways House
Antelope House
Rotunda
Trident House
Shire House
County Hall
S Nicholls
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Ref:
Rev:
HERTS-WINTERPlan-001
05
Date: Sep 05
Page 2 of 35
Hertfordshire Highways
Process:
Develop and Deploy Policies, Plans and Strategies
Title:
Winter Service Operational Plan
Mandatory
Generic
Contract Specific
Guidance
Process
1
CONTENTS
Section No.
1
Topic
Distribution Register of controlled copies
Statement of Policies and Responsibilities
2
Objectives
3
Operational Periods and Priorities
4
Assessment of Need
5
Response and Treatment Times
6
Vehicles, Plant, Equipment and Material Resources
7
Organisational Arrangements & Personnel
8
Weather Prediction and Information
9
Operational Communications
A
Appendices
Hertfordshire County Council's Road Network
B
Depot Locations
C
Calibration Procedures
D
Trained Winter Service Operations Personnel & HCC Duty Officers
E
Sub-contract letter of intent
F
Winter Decision Making Process and Records
G
Glossary of Meteorological Terms
H
Route Plans
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Ref:
Rev:
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05
Date: Sep 05
4
4
5
8
9
10
13
17
20
21
22
24
26
27
28
31
34
Page 3 of 35
Hertfordshire Highways
Process:
Develop and Deploy Policies, Plans and Strategies
Title:
Winter Service Operational Plan
1.0
Mandatory
Generic
Contract Specific
Guidance
Process
1
STATEMENT OF POLICIES AND RESPONSIBILITIES
This Document describes the winter operational service for the Highway Works Contract and covers
Hertfordshire County Council’s 3000-mile road network. It is compiled in conjunction with the contract
requirements - 2800 Winter Maintenance - Amendments to Specification for Highways Works.
The network covered is shown in Appendix A.
Every employee who is involved with delivering the winter maintenance service shall be fully acquainted
with and have access to this plan.
AmeyLafarge aim to provide an efficient and effective winter maintenance service, which as far as
possible allows the safe movement of traffic on Hertfordshire County Council's road network, keeping
delays and accidents caused by adverse weather conditions to a minimum.
The arrangements include utilising personnel and plant available within all operations 24 hours a day, to
enable precautionary salting of the network in accordance with specified response and treatment times.
The operations will be carried out from four winter maintenance depots located at South Mimms, Kings
Langley, Stevenage (Corey's Mill) and Ware (Hoe Lane), using specialised plant and equipment.
Appendix B shows the locations of these four depots.
2.0
OBJECTIVES
To comply with the general duty imposed by Section 41 of the Highways Act 1980: to maintain those
highways maintainable at public expense in a safe condition.
Maintenance and safe condition are not defined, but case law and further sections of the Act assist. They
are generally regarded as connoting fit for the level and type of use that can be anticipated on the
particular road in question.
Section 150 imposes a duty to remove obstructions such as snow and ice and it should be noted that this
duty applies not just to highways maintained at the public expense but also to private streets (i.e. those
over which the public has right of passage).
In seeking to meet both Sections 41 And Section 150 duties, Hertfordshire County Council undertakes to
provide a winter maintenance service which as far as reasonably practical will permit safe movement and
minimise delays and accidents directly attributable to adverse weather conditions.
The courts have recognised that is impossible for all roads to be salted or cleared and that when there is a
transient danger to the elements, the existence of danger for a short time is not necessarily evidence of a
failure to maintain the highway. However, the existence and implementation of an appropriate weather
checking and response system is essential if liability for damage is to be avoided.
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Hertfordshire Highways
Process:
Develop and Deploy Policies, Plans and Strategies
Title:
Winter Service Operational Plan
3.0
Mandatory
Generic
Contract Specific
Guidance
Process
1
OPERATIONAL PERIODS AND PRIORITIES
Hertfordshire County Council uses as a guide in establishing its priorities, the recommendations of the
Local Authorities Code of Good Practice for Highway Maintenance.
Weather in Hertfordshire, like the rest of the Country, is difficult to predict and the occurrence and extent of
wintry conditions varies considerably throughout the season and from year to year.
The winter maintenance season is from 1st October to 30th April. This period may be altered should
conditions dictate.
In order to achieve a reasonable balance between the need for winter maintenance service and the
operational cost, the season can be broken down into three main periods. These periods are shown in the
table below.
3.1
Operational Periods
Period
Time (Months)
Weather Conditions
High
December, January, February
Severe - Probable
Medium
November and March
Severe - may occur
Low
October and April
Severe - not expected
For Practical Operational purposes there is no distinction between High, Medium and Low periods.
However they do serve to highlight the need for a greater degree of availability of resources during the
High period.
Winter maintenance operations are geared to safe movement of traffic but to achieve this there has to be
some distinction between the relative importance of one road compared with another. This is achieved by
identifying in broad bands the relative priority of classes of road as shown in section 3.2.
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Hertfordshire Highways
Process:
Develop and Deploy Policies, Plans and Strategies
Title:
Winter Service Operational Plan
3.2
Route Planning for Carriageways, Footways and Cycleways
3.2.1
Road Priorities
Mandatory
Generic
Contract Specific
Guidance
Process
1
Priority Number
Description
Priority 1

Primary Roads
Priority 2 (a)

Main Distributor Roads

Secondary Distributor Roads

Roads serving significant industrial areas and shopping centres

Scheduled Bus Routes

The growth of mini and midi buses within towns has raised the question
about which bus routes should be singled out for special treatment. In
general terms the small buses have greater manoeuvrability than
conventional single and double decker buses therefore the routes where
these buses operate will not be singled out for special treatment

One road to each village

Urban cycleways open to mopeds where accessible to vehicle mounted or
towed spreaders

Other roads with steep gradients in urban / residential areas

Rural roads with poor drainage where the remainder of the road network
running or standing water is a hazard

The remainder of the road network
Priority 2(b)
Priority 3
Priority 4
Precautionary salting is to be carried out on all priority 1 and 2 roads when conditions dictate that salting is
necessary unless the Duty Officer decides otherwise.
The precautionary salting network routes will be as agreed with the Winter Maintenance review group.
No other road other than priority 1 and 2 roads should be included in precautionary
salting routes.
Some roads already included for precautionary salting have been added historically and may no longer
meet the priorities as shown above. However this does not set a president for other similar roads to be
included in precautionary salting.
From time to time there may be operational reasons why some roads do not receive precautionary salting
on every occasion. Typical reasons are due to roadworks, heavy parking, or attacks on salting vehicles.
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Hertfordshire Highways
Process:
Develop and Deploy Policies, Plans and Strategies
Title:
Winter Service Operational Plan
3.2.2
Mandatory
Generic
Contract Specific
Guidance
Process
1
Footway Priorities
1
High Traffic
Town and City centre and outside local community shops plus footways
linking transport interchanges
2
Medium Traffic
Busy Urban footways leading from housing estates to town and city
centres. Frequently used public amenities. Main streets in villages
3
Low traffic (High Risk)
Housing estates with high incidence of defects due to age of footway
extensive utility trenches or vandalism. Lengths where there are
significant high numbers vulnerable users e.g. outside old peoples homes
4
Low Traffic-Urban
Housings Estates and other urban footways
5
Low Traffic Rural
Little used rural footways
Road closures, diversions and Road Traffic Collisions (RTC)
Rev 05
3.2.3
For planned road closures, consideration should be given to the effect on the salted road network. Usually
it will be the diversion route that is salted, unless the scheme promoter has instructed that the closed
section of road is to also receive salting. Even where a non-precautionary road is to be closed, the
scheme promoter should assess if the increased traffic on the diversion route warrants a change to salting
practices. Where a road closure without special instructions, or an unplanned closure such as an RTC, is
encountered by a salting vehicle, the default will be to salt the alternative route or signed diversion route.
Further instruction may need to be sought for part time closures where the untreated closed road section
may be reopened to traffic while temperature are still below or may fall below zero.
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Hertfordshire Highways
Process:
Develop and Deploy Policies, Plans and Strategies
Title:
Winter Service Operational Plan
4.0
Mandatory
Generic
Contract Specific
Guidance
Process
1
ASSESSMENT OF NEED
The need to carry out winter maintenance in the form of precautionary salting or snow clearing is
determined by the onset of adverse weather. Weather conditions can vary across the County due to local
topography, wind, humidity and altitude. Unlike coastal or mountainous areas the variations in
Hertfordshire are small and often insignificant.
Identification of the need relies very heavily on frequent, accurate weather forecasts. It is only in the last
few years that professional weather forecasters have looked at the specific needs of Highway Authorities.
The result is a growing understanding of the conditions that adversely affect the road network. Many
Highway Authorities including Hertfordshire have invested in Ice Warning Systems, which supply valuable
weather data to forecasters and facilitate more accurate local forecasts.
Monitoring of the weather forecasts shows variations in their accuracy when comparing them with actual
conditions. This variation is not consistent but generally forecasts err on the pessimistic side and
instances of frost or snow occurring when none were forecast is small, generally below 2%. Action taken
on the basis of forecasts can result in a decision to salt roads when no frost actually occurs. Improved
accuracy of forecasting therefore has the potential to save money.
The use of more local data determining the likely weather pattern is a means of limiting the wastage of
resources and assists the weather forecasters providing data to improve decision-making. Hertfordshire
has installed an Ice Warning system known as Icelert for recording weather conditions at a number of sites
on major roads in the County.
The data recorded by this system is available for use by Weather forecasters in their forecast model to
improve the local data on which forecasts for the County are based.
Frost will form when the road surface temperature reaches 0°C. In many instances road surface
temperatures can differ significantly from air or ground temperatures and the appearance of frost on grass
and car windows can be a misleading guide to action required on the roads. As a general rule
precautionary salting must be considered whenever road surface temperatures are forecast to be + 1°C or
below to allow for the inconsistency in weather forecasts.
Some of the difficult conditions facing the officer dealing with winter maintenance (The Duty Officer) are:

Frost forecasts after rain - salting too early could result in the salt being washed away, but salting too
late could result in widespread formation of ice

Freezing conditions coinciding with rain - this almost inevitably results an ice forming. Salting prior to
rain will delay the effect, but unless temperatures rise quickly following commencement of rainfall the
Duty Officer is left with an impossible task

Rapid falls in temperature due to changing cloud conditions - this is very difficult to predict and unless
salting has been carried out in anticipation mobilisation times are too long for salting to be effective
until sometime after ice has formed

During heavy snow falls the resources available and the reliance on up to date information limit the
effectiveness of any operation to keep roads clear. Hindrance by the rapid build up of traffic also has a
significant influence on the effectiveness of any plan of action.
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Hertfordshire Highways
Process:
Develop and Deploy Policies, Plans and Strategies
Title:
Winter Service Operational Plan
5.0
Mandatory
Generic
Contract Specific
Guidance
Process
1
RESPONSE AND TREATMENT TIMES
The effectiveness of any winter maintenance action relies on response at the right time and completion
within a time that is practical.
During High, Medium and Low periods decisions are required on a daily basis. The target time for
reaching a decision is 15:00 hrs. This ensures that the salting crews can be aware of any action that they
are required to take before they leave the depot. It also ensures that the Local Area Offices can be
informed before their crews leave the depot. At weekends the same target is achieved, although crews
will be notified individually at their homes.
For the majority of occasions this time is satisfactory but there will be instances where decisions have to
be made in response to predicted or actual conditions at other times of the day and night.
Spreading of salt is normally undertaken after the evening peak traffic period or before the morning peak.
Under most circumstances frost on the road surface does not form until late evening or early morning, but
where earlier frost is forecast salting will be carried out during the afternoon before the evening peak.
Peak periods are generally 07:30 to 09:00hrs and 16:30 to 18:30 hrs
Salting within these peak periods could delay the salting operation due to heavy traffic flows this could
extend the completion time beyond the required times
Treatment routes and shift arrangements have been organised to achieve defined standards of response
and treatment times on the specified network highway hierarchy.
Definitions:
Response Time is defined as the time taken from the decision to begin precautionary treatment until the
winter maintenance vehicles are loaded, manned and ready to commence actual salting.
Treatment Time is defined as the time as the time taken from leaving the compound in order to begin
treatment of the network through to completion of the treatment.
Response and treatment times are indicated in the following tables - Response and Treatment Times for
Principal Roads and Response Treatment Times for All Other Roads.
5.1
Response and Treatment Times for Principal 'A' Roads
PERIOD
RESPONSE TIME
(HRS)
TREATMENT TIME (HRS)
10grams/m²
20grams/m²
40grams/m²
High Risk
1
2
2
4
Medium Risk
1
2
2
4
Low Risk
1
4
4
8
5.2
Response and Treatment Times for All other Roads
PERIOD
RESPONSE TIME
(HRS)
TREATMENT TIME (HRS)
10grams/m²
20grams/m²
40grams/m²
High Risk
1
2.5
2.5
5
Medium Risk
1
2.5
2.5
5
Low Risk
1
5
5
10
The response time takes account of the distance between home and depot for many of the salting crews
and the time taken for the decision to reach all the crews. The treatment times takes account of the lower
speeds, general road layout and other traffic, and is a balance between a longer period using larger but
fewer vehicles and a shorter period using smaller but more vehicles
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Hertfordshire Highways
Process:
Develop and Deploy Policies, Plans and Strategies
Title:
Winter Service Operational Plan
Mandatory
Generic
Contract Specific
Guidance
Process
1
6.0
PLANT, VEHICLES, EQUIPMENT AND MATERIAL RESOURCES
6.1
Salting Routes and Snow Plough Fleet
The current gritting fleet for season October 2005 to April 2006 is as follows:

18No. Dedicated Gritters 6m³ - New Econ units mounted on Mercedes Benz 1835

4No. Dedicated Gritters 9m³ - New Econ units mounted on Mercedes Benz 1835

13No. Econ Unibodies 4.85m³- new units

16No. Schmidt demountables

2 Econ Cycleway units
All have Econ snowploughs
The gritters will be fitted with equipment, which complies with the requirements of BS 1622:1989
and Clause 2816AR of the Highway Works Contract.
The gritters will be mechanically maintained by Econ Engineering Limited.
Econ Engineering Limited, Boroughbridge Road, Ripon, North Yorkshire, HG4 1UE
Tel: 01765 605 321
For the attention of: Jonathan Lupton
The Schmidt gritters will be maintained by Schmidt UK
Schmidt UK Ltd, Southgate Way, Orton Southgate, Peterborough, PE2 6GP
Tel: 01733 363300
All Contact, Maintenance, Breakdown and Hire arrangements for contract plant should be
initially obtained from Amey Fleet Services.
Amey Fleet Services, Appleford Road, Sutton Courtney, Nr Abingdon, Oxfordshire, OX14 4PP
Tel: 01253 844 710
For the attention of: Ralph Fordham or Clive Brooks
Testing of the spreader and coverage performance of all gritters will be undertaken by Econ
Engineering Limited to ensure capability of symmetrical and asymmetrical spreading in accordance
with Class A1 requirements of BS 1622:1989. Calibration procedures are shown in Appendix C.
All tests shall be completed by the last week in September unless otherwise agreed with
Hertfordshire County Council.
Snowplough blades shall be adjusted so that the wearing strips are within 10mm of the road surface
over the whole length of the blade. Any damage or worn wearing strips will be replaced or turned as
a matter of routine. Snow ploughs and wearing strips shall on every occasion of use be checked,
adjusted and repaired as necessary for optimum performance.
Where prevailing weather conditions dictate, it may be necessary to utilise additional resources.
This may be in the form of labour and plant from various sources.
The existing labour force and plant resources will always be utilised in these situations. In the
unlikely event that the existing resources are not sufficient, additional labour and plant will be
sourced from existing sub-contractors on the network.
Details of contacts for farmers are maintained in a separate register held centrally at Highways
House and at the Area Offices.
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Hertfordshire Highways
Process:
Develop and Deploy Policies, Plans and Strategies
Title:
Winter Service Operational Plan
6.2
Mandatory
Generic
Contract Specific
Guidance
Process
1
SALT
Fine Rock Salt to BS 3247:1989 (minimum 6mm) shall be used as the prime material for combating
snow and ice. It is however recognised that salt is also environmentally unfriendly therefore to gain the
most economic and environmentally satisfactory solution, the minimum amount of salt will be used to
obtain the best effect.
Salt shall not contain any other substances that will cause hazard to human beings, animals, fish or
plant life under normal conditions of use of the salt.
A NAMAS approved laboratory will be used when any Salt Certification is required. Each certification
will be forwarded to Hertfordshire County Council. Certificates will be provided for every 500 tonnes of
salt supplied.
The target rates of spread of salt are given in Section 5 Response and Treatment Times - Principal
Roads and Response and Treatment Times - All other Routes.
To obtain and retain the most economical rates of spread, every gritter will be calibrated and checked
annually prior to 30th September in accordance with current regulations.
Spread patterns and widths of spread will be checked to avoid wastage.
Salt will be supplied by Salt Union Limited.
Salt Union Ltd, De-Icing Business, Winsford Rock Salt Mine, Winsford, Cheshire, CW7 2PE
Salt stockpiles will be stored under covered salt barns at the 4 Winter Maintenance Depots. The
required contract commencement maximum and minimum salt stock levels (during each winter service
period) shall be maintained as table below.
Depot
Required Stock Levels for
Commencement of 2005/06
Season (tonnes)
Minimum Stock
(Tonnes)
Oct Feb
Mar
Apr
Maximum Stock
(Tonnes)
Kings Langley
2900
2000
800
600
3000
Hoe Lane Ware
2900
2000
800
600
3000
Corey's Mill
Stevenage
2900
2000
800
600
3000
South Mimms
2900
2000
800
600
3000
11600
8000
3200
2400
12000
Totals
Salt stock reconciliation will be achieved using monthly physical reconciliation and comparing this with
weighbridge measurements to ensure that minimum and maximum levels as in the above table are
maintained. For the purposes of stock control a mean density of 1.3 tonnes/m³ will be used.
Salt will not be stored :

above the top of the concrete retaining walls (3m high);

more than 6m high at the peaks;

in such a manner that the working face is less than 60° to the horizontal, and avoids the creation of
steep faces liable to collapse.
Salt will be loaded over the sides of the gritters by front end loading shovels until the required amount of
salt is loaded to suit the gritting route.
Weighbridge measures of the gritters as they leave and return to the winter maintenance depots will be
undertaken for reconciliation and stock control purposes.
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Hertfordshire Highways
Process:
Develop and Deploy Policies, Plans and Strategies
Title:
Winter Service Operational Plan
6.3
Mandatory
Generic
Contract Specific
Guidance
Process
1
TREATMENT METHODS
Precautionary Salting
The philosophy behind Winter Maintenance operations is wherever possible, to carry out pre-salting
before ice forms or snow settles on the road. To enable this to be undertaken effectively depends on a
mixture of local knowledge and experience, good local weather forecasts and knowledge of the state of
the road at the time (i.e. is it wet or dry, salt covered or not etc).
Essentially, precautionary salting is planned as a result of weather forecasts to pre-set spread rates.
Rates of Spread for Precautionary Salting
For frost, salt shall be spread at 10-20grams/m².
When frost is expected after rain the rate of salt spread shall be for heavy salting i.e. 20-40grams/m²,
delayed as late as possible to reduce the salt loss by run off unless freezing conditions coincide with
rainfall.
When continuous snow is forecast, salt shall be spread at 20-40grams/m² according to the anticipated
severity of the snowfall. Every effort will be made to ensure enough salt is applied before snow starts to
stick to the road to melt the initial snowfall and to provide a wet surface.
Treatment of Ice already on the Road
When ice has formed on the road surface a salt spread of 20-40grams/² should be used.
Treatment of Snow
Snow ploughing shall be undertaken as soon as snow depths exceed 40mm. Each pass of a plough shall
be supplemented with a salt spread of 20-40 grams/m² depending on the prevailing conditions.
Should the temperature continue to drop and the need for ploughing continues, salt spread rates should
be increased to 40 grams/m²
Light snowfalls may call for ploughing where local drifting has occurred, or to remove snow not dispersed
by traffic. This may occur where traffic is reluctant to use outer lanes of dual carriageways, or at night
when traffic is light.
If snow depths reach 120mm, or when tackling drifts or when working on gradients, ploughing may be
undertaken without salting as the weight of the load may aid vehicle traction. As soon as the situation is
under control spreading will be resumed.
Where heavy or prolonged snowfalls accumulate on well-used footways, arrangements will be made to
clear a route for pedestrians as soon as practical. If freezing conditions persist, footways cleared of snow
should be given a light salting to melt the ice.
Clearance of snow from less heavily used footways will depend upon the anticipated duration of freezing
conditions. Provided the more heavily used footways have been cleared and freezing conditions are
expected to persist, then these footways may be cleared
Treatment of Hard-Packed Snow and Ice
If hard packed snow and ice conditions exist at temperatures down to -5°C and provided that this layer is
no more than 20mm thick, removal shall be by successive salt spreads at 20 - 40 grams/m².
At temperatures between -5°C and -10°C where hard packed snow and ice is more than 20mm thick it
may be necessary (in exceptional circumstances) to complete two runs. The first run will involve
spreading 5mm down sand or grit. The second run will be at the required salt spread at 20-40 grams/m2.
Approved:
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Contract Specific
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Process
1
7.0 ORGANISATIONAL ARRANGEMENTS AND PERSONNEL
All works associated with winter maintenance operations will be carried out in accordance with
AmeyLafarge Area Health and Safety Plans.
A schedule of operatives involved in the winter service operations can be found in Appendix D - Personnel
Schedule.
In order to provide the required response to weather conditions, winter service operations staff will operate
a combination of standby at home, standby at compounds, in addition to normal and continuous shifts.
Other groups may be employed directly by AmeyLafarge where health and safety requirements for
working on the highway can be met. Beyond normal precautionary salting operations, the W inter Service
Manager may call upon additional resource to assist with secondary salting and clearance of snow and
ice. The level of this resource will be dependent on the severity and extent of the conditions. Resources
come from Farmers, other Local Contractors, and District/Borough Council staff. Availability of resource
differs from one District/Borough to another depending on what contractual arrangements are in place or
whether a Direct Labour Organisation exists.
A sample letter of sub-contract intent is contained within Appendix E.
Duty Schedules and Standby Rotas will be available centrally at Highways House and at Area
Offices.
Definitions:
Call Out is defined as off duty personnel available for duty as demand arises but without any prior
commitment to be available.
Stand by is defined as personnel committed to be available to report to the depot or direct to a route
within 1 hour of being called out from elsewhere or home.
Normal shift is defined as personnel on duty at the depot or at a work place during normal working hours.
Continuous shift is defined as personnel on duty at the depot on patrol, gritting or ploughing route.
In all cases a weather controller, duty supervisors and labour are provided to ensure that treatment of the
whole network can be completed in accordance with Clause 2802AR of the Highway Works Contract.
7.1
DECISION MAKING
Hertfordshire County Council's Duty Officer will instruct the AmeyLafarge Winter Service Manager by
1500hrs each day during the operational winter period whether to precautionary salt or confirm if the level
of standby is required, using telephone links and a further email or fax confirmation.
The AmeyLafarge Winter Service Manager will communicate the appropriate action required to
AmeyLafarge operatives.
All operatives involved in the winter maintenance service will be trained to National Vocational
Qualification (NVQ) standard. Training requirements for operatives will be assessed and reviewed
periodically by the Winter Service Manager and using the Training Request Form, Form Ref. 1000-PLC HR506/03.
Decision-making will be made along the guidelines shown in Appendix F, Winter Decision-Making Process
and Records.
During the High, Low and Marginal periods daily weather forecasts specific to Hertfordshire County will be
available to the County Duty Officer under contractual arrangements with the Forecast Provider. The Duty
Officer will be able to speak to the Forecaster to discuss the forecast received or general weather
conditions at any time of day or night.
Using the forecast information and his knowledge of existing road conditions obtained from the Icelert MK6
system the County Duty Officer will be responsible for determining the appropriate action for the whole
County. The Duty Officer will clearly state when precautionary salting should commence and the rate of
spread to be used. No system of visual inspection will be utilised although observations reported through
normal daytime operational activities would be valuable in assessing existing road conditions.
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Normally precautionary salting will be carried out outside working hours. The Duty Officer must decide
whether this should be after the evening peak or before the following morning peak.
Salting of the Priority 3 and 4 network will only be when instructed by the HCC Duty Officer.
If an instruction is issued the priority 3 network will only be treated when all priority 1 and priority 2 roads
are operational to the standards set down in this plan.
If an instruction is issued the priority 4 network will only be treated when all priority 1,2 and 3 are
operational to the standards set down in this plan.
7.2
SNOW CLEARANCE
The decision to move to the snow clearance operation shall be made by the HCC Duty Officer following
consultation with the Winter Service Manager and Salting Supervisors.
The Winter Service Manager and his team will then control this operation.
Until a pattern becomes clear the majority of ploughing vehicles should be concentrated on priority 1 and
2(a) roads. Sufficient resource must be deployed to these roads to establish as rapidly as possible one
clear lane in each direction. In the most severe cases it may be necessary to deploy all available resource
to these roads. It is essential to maintain free flow on the major routes to minimise delay and unsafe
conditions. These routes will also provide arterial network to enable plant and equipment to reach lesser
priority roads when necessary.
When the Winter Service Manager is satisfied that the priority 1 and 2(a) roads are operational to the
standards set down, he should deploy the ploughing vehicles to priority 2(b), then priority 3 and 4.
The operational resource will not move from priority to priority until all the higher priority roads are to the
operational standards.
When a call is received regarding the build up of snow from a member of the public, the caller should be
informed that all available resources have been deployed in the deliverance of the Winter Service
Operational Plan, and all roads will be treated by their priority rating.
These priority roads have been predetermined and will be treated in the order as stated in the plan. This
may mean that once all main routes are clear and resources allow attendance at the lesser priority roads,
the thaw may have already set in.
When attending to the network in priority order should reports of ice or snow be received on a priority
already treated, then that priority should be revisited. Should the report of ice be on a salted route then
that information would be passed to the Winter Service Manager who will discuss this with the HCC Duty
Officer.
Throughout the snow clearance and treatment of the priority 3 and 4 the Winter Service Manager will keep
the HCC Duty Officer informed. Each Area office will be kept up dated of the operation and given
constructive feedback of the situation through AmeyLafarge Area Managers.
Specific requests from the police and area offices will be co-ordinated through the AmeyLafarge Network
Manager but the total resource will be controlled by the Winter Maintenance Manager and his deputies.
This will ensure a consistent approach countywide enabling updated reports on the situation to be issued
both at local and central level. The reports should include details of closed roads.
The HCC duty officer will be kept up to date on the situation at all times via the Winter Service Manager or
his deputies at a maximum of 2 hour intervals unless another time limit is agreed at a local level.
Clearance of Snow and Ice on Footways
As with carriageways the footways will be dealt with in strict priority order, and will be treated with the
same priority system.
The Environment Systems unit will determine the priority of the footways with input from the area offices.
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7.3
Mandatory
Generic
Contract Specific
Guidance
Process
1
REPORTS OF ICE ON THE PUBLIC HIGHWAY
Information from the police or emergency services will be actioned
Clarifications should be sought as to whether the report relates to one specific site, or a general area. Try
to clarify that the slipperiness is in fact caused by ice, and is not either a diesel spill or a result of the salt
itself which will be slippery when in solution.
Reports should be dealt with, not necessarily by direct action, but within reasonable priorities as described
in this plan.
Report of ice on a precautionary salting route
All reports of ice on the precautionary salting routes will be actioned.
If precautionary salting has not been instructed, contact the HCC Duty Officer who may then consider
instruction of a full precautionary salt depending on forecast conditions.
If a salting outing is due to commence within less than 1 hour, no further action is required, as the
instructed salting will treat this site.
If precautionary salting has already taken place, first contact the Salting Supervisor to determine if plant
breakdowns have occurred. If this is not the case, contact the HCC Duty Officer as the applied salt
quantity may not be sufficient to clear the site, and further salting action may be considered depending on
forecast conditions.
Report of ice on a non-precautionary salting route.
Only the following reports will be normally actioned (unless post salting is instructed, see below)

Request following an accident where ice is a contributory factor

Where an incident has caused a significant increase in traffic onto a non-precautionary salting route.
(Note, during precautionary salting outings, signed diversions routes for temporary road closures will
be salted as a matter of course. A closure occurring after a salting run will not have had its diversion
route salted. A diversion route removed after a salting outing has taken place may have not have had
the normal precautionary road salted as it was closed).

Any other incident causing a significant increase in traffic, e.g. a motorway closure, or major event.

After fire-fighting activities where significant amounts of ice (or potential for) on the highway surface
have occurred.

Where seepage or localised flooding has occurred and there is significant amount of ice (or potential
for ) on the highway surface

Where a maintenance failure has been identified and has not yet been fixed

Burst pipes. The leak will be washing away salt even if precautionary salting has taken place. In the
first instance the water authority responsible, under the New Roads and Street Works Act, must be
given the opportunity to remove the ice. Hertfordshire Highways can arrange salting and recharge. If
the owner of leak is unknown, action should be taken to treat the ice or potential for ice
Such action would normally be in the form of hand salting, or salting using a reserve gritter. It should be
limited to the area affected and is not intended to treat the whole road or footway
In extreme circumstances it may be necessary to sign areas, or cone off roads or areas of Highway if the
police feel the potential hazard is great.
The target time to respond is 2 hours.
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Routes to schools
Whilst it is recognised that walking routes to schools are increasing, it is not practical to undertake salting
on footways, or roads, to all schools in the county. Those schools serving the highest numbers of pupils
are those most likely to be serviced by scheduled bus services or high usage footways so are likely to
receive pre or post salting. Where it is felt that untreated roads or footways leading to a school (or indeed
the untreated areas within the school itself) pose a significant risk to pupils, the headteacher may decide
that it is a safer option to close the school during severe weather. The headteacher will also be
considering other pressures effecting the operation of the school such as advice from police or motoring
organisations that journeys should not be made which will effect availability of teaching staff and other
services at the school should it remain open.
Post Salting
When prolonged sub zero temperatures are forecast, temperatures below 0ºC
For a long period of longer than 48 hours, post salting will take place. This allows a programmed approach
to dealing with ice off of precautionary salting routes.
The public can be assured that “Hertfordshire Highways will deal with ice on the highway with the
reasonably expected resources as required by the Winter Service Operational Plan, treating the
highest priority roads first.”
These priorities have been predetermined and will be treated in the order as stated in the plan,
which may mean that by the time all main routes are clear and resources allow attendance at the
lesser priority roads the thaw may already have set in.
Additional salting resources may be used during this period.
Snow
Snow fall of less than 40mm will not normally require any further action than precautionary salting unless
prolonged sub-zero temperatures are forecast.
For snow falls in excess of 40mm or when drifting occurs, post salting will take place as soon as is
practicable. This allows a programmed approach to dealing with ice on non-precautionary salting routes.
The public can be assured that “Hertfordshire Highways will deal with snow on the highway with the
reasonably expected resources as required by the Winter Service Operational Plan, treating the
highest priority roads first.
These priorities have been predetermined and will be treated in the order as stated in the plan,
which may mean that by the time all main routes are clear and resources allow attendance at the
lesser priority roads the thaw may already have set in.
Additional salting resources may be used during this period.
Reports of ice off the public maintainable highway

No action will be taken to treat ice on private roads(i.e. where there are no public right of highway
rights)

Some private arrangements may be in place with AmeyLafarge.
Salt Bins
Salt bins are provided in over 700 locations across the county for 'self help' during icy highway conditions.
Establish if the reported site is near a salt bin and self-help may provide a more effective result than
adding the site to a prioritised list.
These bins will be refilled after a prolonged snow or ice period.
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Railway Level Crossings
No salt should be spread across railway crossings
If there is a problem with ice or snow accumulations at these locations the Railway authority must be
consulted before any action is taken.
Boundary Arrangements with Neighbouring Authorities
There are a number of local arrangements with neighbouring authorities where a road length will be salted
crossing over the boundary.
This is done where a road crosses in and out of a boundary or where it makes operational sense to
complete road lengths before turning the vehicle around. However, the default is that a salting decision for
the county of Hertfordshire should see all the precautionary salting routes treated, and therefore Herts
Highways salting routes will include salting up to the boundary.
All arrangements with neighbouring authorities must be agreed through the strategic client.
Agreed arrangements are as follows:
-
A111 Stagg Hill from Cockfosters Road to M25 J24 (London Borough of Barnet)
-
A1005 The Ridgeway to M25 J24 (London Borough of Enfield)
Whilst it is not possible to document detailed arrangements for every scenario which may occur during
severe weather , Hertfordshire Highways will seek to fulfil its obligations under the Traffic Management Act
to ensure expeditious movement of traffic on its own roads, and on those of adjoining authorities, by
providing assistance to its neighbours, and expects the same in return.
Agreements on mutual aid exist with the agents of the Highways Agency where their Motorways and trunk
Roads run through the county.
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Mutual Aid
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8.0 WEATHER PREDICTION AND INFORMATION
Forecasting Services
Winter Weather forecasting service throughout the winter service period 1 st October 2005 to 30th
April 2006 inclusive will be provided by PA Weather Centre:
PA Weather Centre Ltd, PA News Centre, 292 Vauxhall Bridge Road, London, SW1V 1AE
For the attention of Alan Howling, RoadCast Manager
A full forecasting service will be available throughout this period.
The Weather recording system, Findley Irvine ICELERT MK6, is provided and maintained by
Findley Irvine. Full contact details are:
Findley Irvine Limited, 42 / 44 Bog Road, Penicuick, Midlothian, Scotland, EH26 9BU
For the attention of Tom Findley, Business Development Manager.
There are 9 Weather-recording outstations located on the Hertfordshire County Council Road Network
including 3 forecast outstations. These are detailed in the table below
The Visala outstation will be maintained via Findley Irvine with the approval of Visala.
Surface sensors are cleaned pre-season and mid-season or more regularly where required. It is
recognised that surface sensors give an indication of salt concentrations but should be used as a guide
only in the decision making process.
SITE LOCATION
O/S GRID REF.
PROVIDER
A505-LL
A505 Lilley
TL 126 263*
Findley Irvine
A120-BST
A120, Bishops Stortford
TL 486 233
Findley Irvine
B136-BGH
B1368,North of Hay Street, Braughing
TL 393 268*
Findley Irvine
A119-STP
A119,North of Stapleford
TL 310 173
Findley Irvine
B487-HH
B487,Redbourne Road, Hemel Hempstead
TL 093 107
Findley Irvine
B488-TRG
B488,New Mill, Tring Wharf
SP 927 131*
Findley Irvine
A4147-HH
A4147, Maylands Avenue, Hemel Hempstead
TL 077084
Findley Irvine
U53-OFF
U53, School Lane, Offley, Bridge Deck Site
TL 141 275
Findley Irvine
A41-CR
A41 Cow Roast
SP 953 097
Visala (via FI)
C183-HC
C183 (Old A10) North of High Cross, near Barwick
TL 366194
Visala (via FI)
*Indicates forecast outstations
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SITE REF.
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Forecasts
4 Weather forecasts will be provided no later than 13h00 daily throughout the operational winter period:

24hr General

2-5 Day

Site Specific (from 3 forecast outstations)

Morning Summary (to be provided daily by 08h00)
A glossary of terms used in Meteorological Forecast can be found in Appendix G - Glossary of
Meteorological Terms.
Forecast information provided will include the following details;
24 Hour General
This shall include for, in text format :
General synopsis with location and timings over the following 24 hour period.

Minimum air, road surface and bridge deck temperature predictions for agreed climate /
administrative zones and the timing of 'zero crossing' if appropriate.

Probability of precipitation or deposition on road surfaces with location and timings.

If appropriate, the location and timing of snowfall predicted depth and type, the direction from
which the snow will arrive, probability of drifting and the height above which accumulation is
likely.

Location and timing of thick (<200m visibility) or freezing fog formation.

Severe storm and/or gale weather warning, location, timings including nature of severity e.g.
Wind speed and direction.

The confidence level of all predictions shall be specified as low, medium or high.
2-5 Day

General synopsis and trends with specific reports for day/night of days 2 and 3

Table of minimum air and road surface temperatures, positive or negative prediction of
hoarfrost, ice, snow, drifting rain and fog with confidence factor for days 2, 3, 4 and 5.
Site Specific
These shall be provided from the 3 identified forecast ICELERT outstations, as follows:

Graphic representation against time of predicted road surface temperatures and surface
condition.

Associated textual forecast (site specific), including thermal map type and forecast confidence
level.
As necessary, table of snow probability showing time and predicted accumulations.
Morning Summary (to be provided by 08h00)

Textual summary of the previous 18 hours (14h00 - 08h00), highlighting actual minimum road
surface temperature, time of occurrence and location.

Brief forecast for following 24 hours with specific reference to road surface condition.
If minimum road surface temperatures are predicted to be below +5°C by the general 24 hour and/or 2-5
day weather forecast, updates of both forecasts are to be issued by 18h00 including advice of 'no change'.
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Forecast Monitoring and Amendments
Actual weather and road conditions will be monitored via Findley Irvine's Weather Recording System and
forecast amendments will be issued as often as necessary, but wherever possible before midnight or
whenever they may be the need to initiate or change the response when none was originally planned.
Report on Service Delivery
An 'End of Season' report will be provided at the end of each winter Service Period detailing the general
description of the weather conditions throughout the period and providing an end of season analysis of the
forecast accuracy throughout the period.
Performance Standards
Weather forecasting information from the 3 forecast outstations will be monitored to ensure that the
following KPI's are maintained throughout the season;

A minimum 85% accuracy for the Frost / No frost analysis for critical nights

A maximum 20% 'Miss Rate'.

A maximum 25% 'False Alarm Rate'.

A maximum -0.5 'Forecast Bias'.

A maximum 1.75 'RMS Error’
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9.0
Mandatory
Generic
Contract Specific
Guidance
Process
1
OPERATIONAL COMMUNICATIONS
Communication
Two-way communication between all parties involved in the Winter Operational Service activities is
essential at all times. Due to the wide range of personnel and activities involved, modes of communication
will include but not be limited to: two-way radios; mobile phones; landline phones; computer links; and
TR2020B Extended (FIH) protocols.
Weather Forecast Provider
ICELERT communications will be via the website ICELERT.net
The County Duty Officer and the Winter Service Manager will have direct contact with the Weather
Forecaster via standard telephone links. This Facility will be limited to authorised personnel only.
Master Station to County Duty Officer
The Duty Officer will be able to gain access to the information stored on the Findley Irvine ICELERT
Master Station via secondary mobile computers with standard remote dial-in telephone and modem links.
Access will also be provided to a restricted password protected web-site giving software and hardware
support, technical documentation and software updates.
County Duty Officer to Winter Service Manager
The County Duty Officer will arrange to convey the daily action required, by 15h00 daily, to the Winter
Service Manager either in person or using standard telephone links.
As a routine, the daily action will be further confirmed the same day in writing, by fax or by e-mail using an
agreed format.
Outside normal working hours, the County Duty Officer will still contact the Winter Service Manager.
In the event that the Winter Service Manager is not obtainable, all communication will be via the
Emergency Duty Manager.
Winter Service Manager to Operational Team
The Winter Service manager will communicate to the Operational team on Winter Maintenance Standby
by standard telephone link, mobile phone links or two-way radio links dependent on the time that
notification is given.
During precautionary salting operations, communications with duty supervisors and other gritters will be
via two-way radio links or mobile phone links.
Client Control to Client in the field
Communication between client personnel controlling operations and those supervising work in the field is
only necessary during snow clearing operations. In these circumstances it is essential to maintain a flow of
up to date information to the control desk to ensure effective use of available equipment. Telephone and
two-way radio contact will be used.
In establishing the modes of communication, AmeyLafarge will take into account some of the limitations of
some mobile equipment and ensure that the misuse / malfunction of such equipment does not hinder the
communication process. Modes of communication may need to be altered as the contract progresses.
Joint Manning of Control Desk
During severe weather conditions, a control desk for joint manning of operations will be set up at the
Highways House, Welwyn Garden City or at the four Area Offices unless otherwise agreed between the
County Duty Officer and the Winter Service Manager. During severe conditions, the police may request
that the control desk be set up at Police HQ where both the County Duty Officer and the Winter Service
Manager will be present. The Highways Agency may also have a control desk at Police HQ.
The Winter Service Manager will take full operational control of all activities being co-ordinated and will be
the lead member of the team. The Winter Service Manager will select the team required to assist in
manning of the control desk
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APPENDIX A
HERTFORDSHIRE COUNTY COUNCIL'S ROAD NETWORK
Salted network
Highway network
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APPENDIX B
DEPOTS
Railway Terrace, Kings Langley
Amey Lafarge
Highway Maintenance Depot
Langley Wharf
Railway Terrace
Kings Langley
Hertfordshire
WD4 8FE
Hoe Lane, Ware
AmeyLafarge
Highway Maintenance Depot
Hoe Lane
Ware
Hertfordshire
SG13 9EY
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Corey's Mill Stevenage
AmeyLafarge
Highway Maintenance Depot
Corey's Mill
Hitchin Road
Stevenage
Hertfordshire
SG1 4FD
South Mimms, Potters Bar
AmeyLafarge
Highway Maintenance Depot
Charleston Paddock
Old St Albans Road,
South Mimms
POTTERS BAR
EN6 3ND
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APPENDIX C
CALIBRATION PROCEDURES
LINKED 'J' SPREADER 12v or 24v
For further information please contact:
ECON Engineering Ltd.
Sales, Service & Parts
Boroughbridge Road, Ripon, North Yorkshire, HG4 1UE
Tel: 01765 605321
fax: 01765 607487
E-mail: sales@econ-eng/co.uk
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CALIBRATION PROCEDURE FOR LINKED
'J' SPREADER 12 OR 24V
Always check calibration before connecting downloader.
A downloader and calibration kit are required to carry out the above. Jack vehicle up and support all
driven axles safely on axle stands.
Ignition off, plug in downloader, start engine, highlight and select "Password set". Enter password
"076". Highlight and select "Other menus". Highlight and select "System set up". Check correct
registration or fleet number using number keys and the "" key on the downloader. Next the "Speed
Input" should be set up press "Yes" on the downloader and follow instructions. If you press "Yes" you
must drive the vehicle at 40kph and follow instructions.
On magnet and probe spreaders spinner is set for 2 pulses per rev. On in-built to motor, signal is 5
pulses per rev.
If required adjust date and time accordingly. NB remember BST.
Spinner, door or conveyor can be calibrated in any order refer to speed sheet for correct calibration data.
Press "Menu" highlight and select "Calibrate MFC - Machine type is linked - change - answer NO".
To Calibrate Spinner:
Spinner is "open loop". Since March 1998 most 'J' spec machines are fitted with dual spinner speeds.
Follow instructions on downloader and turn spinner to no.1 with Rate between 5 & 25 g/m 2 adjust speed
of spinner rpm using  or  to speed on chart. Press "Select" key to store speed. Move spinner switch
to position 2 and repeat through all positions. After speed no. 2 has been set move Rate above 25g/m 2
and set all against the chart. When finished press "Menu" and follow instructions on downloader.
To Calibrate Door:
Ignition on only required. Enter "Calibrate MFC" "Machine type Linked" "Calibrate Door" answer
"Yes" follow text on downloader. Use  or  keys to set vertical door height for position no.1, note that
rate switch should be on 5 or more while door heights are being set. Go through and set all doors for
each spinner speed setting. Next turn rate off and spinner off and set door to the fully closed position,
(should be just off belt 2-3mm). Turn "off load" switch on, and set door fully open, (allow door actuator
to reach end of stroke then lower by 5mm), store and press Menu to end.
Conveyor Speed
Conveyor speed is affected by three items:
1. 40kph signal
2. Threshold signal
3. Conveyor speed
Each will have an effect on final calibrated speeds so it is important that each one is set accurately.
Set engine running at tick over.
To set up "Conveyor Threshold" - answer "Yes" - "Has speed been set up" answer "Yes". Follow
text on downloader, use  or  keys to adjust and give "Creep" speed and store. Press menu to end.
Set engine running at 1500 rpm.
"Calibrate conveyor?" - answer "Yes" - "Has speed been set up" - answer "Yes". Follow text on
downloader set Rate to 40g/m 2 and spinner to position 1 set conveyor speed at 9.4rpm and store. Move
spinner switch to 2 and set conveyor at 9.4rpm again store and repeat through all spinner positions
leaving rate set at 40g/m 2. Leave spinner on 11, turn Rate switch to 35g/m2, set conveyor speed to
8.2rpm, store. Set remaining conveyor speeds leaving spinner switch on no.11, Press "Menu" to end.
When finished turn control box off and on. Check all belt speeds at 40, 30, 20 & 10kph.
Note: belt speed should not alter for any spinner position.
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1
APPENDIX D
TRAINED WINTER SERVICE OPERATIONS PERSONNEL
& HCC DUTY OFFICERS
Surname
Adams
Adams
Allen
Bannister
Barrs
Berry
Berry
Bevans
Blomiley
Bowyer
Brodie
Brownsell
Capon
Cappleman
Carlin
Carter
Clark
Cokayne
Colgate
Cooke
Craig
Darcy
Davidson
Davidson
Dowling
Dowling
Everett
First Name
Mark
Wayne
Dylan
Derek
John
Justin
Peter
James
Sean
Raymond
Ronald
William
Owen
Jason
Michael
Scott
David
Steven
Matthew
Jeffrey
Gary
Colin
Terry
Hamish
Carl
Mark
Paul
Surname
Field
Filmer
Flack
Ford
Gentle
Glasscock
Gower
Gwilt
Haigh
Hammond
Harris
Henderson
Herbert
Hills
Hodsden
Holden
Holt
Hoy
Huggins
Johnson
Kenealy
King
Lang
Lea
Mardlin
Marshall
Martin
First Name
Surname
First Name
Stephen
Clint
Robert
Andy
Christopher
Barry
Michael
Paul
Wayne
David
Jez
Brian
Donald
David
Graham
Keith
Michael
Andrew
John
Robin
Richard
Philip
John
Colin
David
Brian
Chris
Matthews
Maunders
McMahon
Nairne
Norris
Olley
O'Shea
Page
Parker
Pearce
Potton
Pratt
Rice
Routledge
Saunders
Sheehan
Smith
Stapleton
Stevens
Taylor
Taylor
Thomas
Triggs
Tucker
Whiskin
Young
Wright
Malcolm
Ricky
Dave
Russell
Michael
David
Martin
Kelvin
Kelly
David
Melvyn
John
Dino
Brian
John
John
Keith
Ian
Robin
Dennis
Rob
Jeffrey
Jeffrey
Paul
Simon
Dave
John
Additional resource (direct and/or subcontractors) will be used to manage and deliver winter
service operations to a level and duration appropriate to winter events, conditions and duration.
HCC Duty Officers
Mark Fell
Rob Jepson
Jon Prince
Abigail Foster
Chris Allen-Smith
Mobile
Office
Home
07785 311524
07771 938790
07736 773169
07887 610052
07770 604082
01707 356557 (56557)
01707 356562 (56562)
01707 356569 (56569)
01707 356563 (56563)
01707 356573 (56573)
01992 410717
01279 651652
01992 535663
01923 353468
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Rev 05
The following have undertaken Winter Service Training - Understanding Weather Forecasts, to
carry out the role as Duty Officer
Hertfordshire Highways
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APPENDIX E
Sub-Contract Letter of Intent
Date
Dear Sir,
Re: Snow Clearing 2005/2006
I am writing to confirm your assistance should it be necessary in the clearance of snow from the
highway network.
It is essential that you clearly understand that payment will only be made for work requested by
Hertfordshire Highways for which an order reference will be placed with yourselves.
In extreme cases where problems exists and you consider that you should be working and have
not been contacted, please telephone this office on **insert contact number* during normal
working hours. In 'out of hours' situation, please ring **insert contact number** where the
standby officer will answer your queries.
It would be appreciated if you could send details of what equipment you have.
Accounts for work done should be rendered to this office and must clearly show dates and times
worked, with the location of roads cleared. Plant and labour should be itemised in accordance
with the attached schedule of rates with the BHP of tractors, excavators, bucket sizes etc.
clearly identified.
Please contact **insert name** on the above office number and confirm your availability and
arrange for details of your CIS card and acceptance to be completed, at the above address.
I enclosed the nationally agreed rates for your reference.
May I take this opportunity of thanking you in advance for your assistance, which may be
invaluable, should extreme weather conditions arise.
Yours sincerely
Stuart Nicholls
Project Director
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APPENDIX F
WINTER DECISION MAKING PROCESS AND RECORDS
Decision making procedure
A suggested procedure for decision making on precautionary salting is shown on page 30 in
Table H1. This should be modified, as necessary to suit local circumstances and the timing of
operations should be mainly influenced by the timing of expected weather conditions rather than
other considerations. The following notes relate to the letters on the table:
A
Particular attention should be given to the possibility of water running across
carriageways and other running surfaces e.g. off adjacent fields after heavy rains,
washing off salt previously deposited. Such locations should be closely monitored and
may require treating in the evening and morning, and possible other occasions.
B
When a weather warning contains reference to expected hoarfrost considerable deposits
of frost are likely to occur. Hoarfrost usually occurs in the early morning and is difficult to
cater for because of the probability that any salt deposited on the dry road too soon
before its onset may be dispersed before it can become effective. Close monitoring is
required under this forecast condition which should ideally be treated just as the
hoarfrost is forming. Such action is usually not practicable and salt may have to be
deposited on a dry road prior to and as close as possible to the expected time of
condition. Hoarfrost may be forecast at other times in which case the timing of salting
operations should be adjusted accordingly.
C
If, under these conditions, rain has not ceased by early morning. Crews should be called
out and action initiated as rain ceases.
D
Under these circumstances rain will freeze on contact with running surfaces and full pretreatment should be provided even on dry roads. This is a most serious condition and
should be monitored closely and continuously throughout the danger period.
E
Weather warnings are often qualified by altitudes in which case differing action may be
required from each depot.
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Table H1
Predicted
weather
forecast
Road surface
temperature
Precipitation
ETC.
Expected to fall below freezing – see note (E)
May fall below
freezing
No rain
No rain
No hoar frost
No hoar frost
No fog
Expected hoar
frost
Expected fog
No fog
Expected rain
Expected rain
Possible rain
Before
freezing
During
freezing
Possible hoar
frost
Possible fog
Wet
1
1
1
3
See Note (C)
1
See Note (D)
1
Wet Patches
2
See Note (A)
2
See Note (A)
2
See Note (B)
3
See Note (C)
1
See Note (D)
1
Dry
6
See Note (A)
6
See Note (A)
1
See Note (B)
3
See Note (C)
1 or 5
See Note (D)
5
Pre-salted within last 24 hours
with no rain since
6
See Note (A)
6
See Note (A)
4
See Note (A)
3
See Note (C)
1 or 5
See Note (D)
5
ACTION
1.
2.
3.
4.
5.
6.
Salt before frost
Salt wet patches before frost
Salt after rain stops
Supervisor inspect
Supervisor inspect with crew standing by in depot for instructions
No action
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WEATHER & SALTING ACTION RECORD – 2005/2006
Duty Officer: -
Day
Date
Time
Last Night’s Weather: - (Morning Summary of previous 18 hours)
Cloudy
Clear Sky
Roads min
yes
yes
Rain
Roads
No
No
0C
yes
wet
No
Dry
Sleet
Frost Air
Blkd Roads
yes
yes
yes
no
no
no
Snow (mm)
Frost Grnd
Ice on Rds
yes
yes
no
no
no
Comments:-
Today’s Forecast
Confidence Level - low / medium / high
24 Hour
2-5 Day
Min Air Temp.
ACTION DECIDED AT
0
C
Min Road Temp.
C
Min Bridge Temp
0
C
hrs (Note any Duty Manager / Secondary Duty Officer checks)
Routes
All routes
0
Proposed Action
Time
Salt at 10gms from all depots (20g on A41/A505)
Salt at 20gms from all depots
Salt at 2 x 20gms, or 40gms from all depots
Standby at home
Standby in the depots
No Action
Informed: - Works Team Out of Hours Reception (yes/no)
Message sent to ICELERT (yes/no)
Action amended to at
hrs
Routes
Proposed Action
Time
Informed: - Works Team Out of Hours Reception (yes/no)
Message sent to ICELERT (yes/no)
Useful Telephone Nos.
Forecaster (PA WeatherCentre)
Out of Hours Reception
0845 603 0563
01707 356510
Additional information/records of telephone conversations may be detailed on reverse of this sheet.
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APPENDIX G
GLOSSARY OF METEROLOGICAL TERMS
Accretion. The build up of snow on objects such as overhead cables, road signs and tree branches. It occurs when wet snow,
with temperatures close to freezing, is accompanied by a strong wind. The wet snow freezes on to objects under pressure of
the wind. The build up of snow can be quite large, and can cause damage to cables and trees.
Air frost. This occurs when air temperatures (measured between 1 and 2 metres above the ground) fall below zero degrees
Celsius.
Black Ice. Clear ice which forms on roads due to the freezing of standing water. Occasionally it may be formed by the
transformation of hoar frost, under pressure from car tyres. The name black ice is used, as the road blacktop can be seen
through the clear ice. The term is much beloved by the media, but is used less frequently in road weather forecasts.
Bureau. This refers to an instation that is shared with other authorities (see Instation, Masterstation and CPU).
Climatic Domain. An area of a county with broadly similar climatic characteristics e.g. an urban area, or a high level area, or a
coastal area. See Forecast Site.
Condensation. This is the change of state of water vapour to liquid water, thus forming a thin film or mist of water on surfaces
such as roads. During the process, heat is released (see Latent Heat, Dewpoint).
Confidence Factor. Used by weather forecast organisations to give guidance to highway engineers on the likelihood of
forecasts having to be subsequently amended. Confidence HIGH means that amends are unlikely and confidence LOW that
amends are likely. Some use is made of MEDIUM confidence, although usage is discouraged, as it can be confusing.
Damped. This is the thermal map type that occurs on cloudy, windy nights. Temperature differences along a stretch of road
are at a minimum (see Thermal Mapping).
Deliquescence. The chemical property whereby a substance will absorb water from the air before the air is saturated. Salt is
deliquescent and will absorb water from 80% relative humidity upwards (see Relative Humidity).
Deposition. This term covers the change of state from water vapour to ice without going through the liquid water stage (see
HoarFrost).
Depth Temperature. The temperature measured at around 30cm below the road surface (usually below the main asphalt
layer). It can give indication of ground heat flux (see ground heat flux).
Dew. Liquid water formed on a surface by condensation from the atmosphere.
Dewpoint. The temperature to which a sample of air must be cooled for condensation to take place. Dewpoint can be
measured directly by instrumentation e.g. road sensors.
Drifting. The movement of snow (usually powder snow) under the influence of wind. Snow need not be actually falling for
drifting to take place.
Dry adiabatic lapse rate. The temperature fall with height within a sample of air before it becomes saturated. The rate of fall is
0.98 degrees Celsius per 100 metres (around 3 degrees Celsius per 1000 feet).
Evaporation. The change of state from water to water vapour. The process takes in heat and causes cooling (see Latent
Heat).
Extreme. The thermal map type that occurs on calm, clear nights. Temperature differences along a stretch of road tend to be
at their maximum (see Thermal Mapping).
Flash Frost. The rapid build up of hoar frost on roads around sunrise. Roads can change from dry to a significant cover of
hoar frost within 15 minutes (see Hoar Frost).
Fog. The suspension of water droplets in air at or close to the ground.
Forecast Site. A road sensor site for which a graphical forecast is provided.
climatological domain, see climatological domain.
It is usual to have one forecast site per
Freezing Fog. Fog which forms when air temperatures are below freezing. The fog droplets remain in the liquid state, but will
freeze on contact with trees and other objects, and under some circumstances the road surface (see Rime).
Freezing point. The temperature at which pure water will change to ice (although strictly it is the temperature at which ice
melts) in practice 0.0 degrees Celsius.
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Freezing Rain. A very dangerous condition where raindrops (from warmer air aloft) fall on to surfaces below freezing, thus
freezing instantly and causing widespread ice. Fortunately, rare in the UK. Most likely to occur at the end of a prolonged spell
of cold weather.
Frequent. Used in conjunction with showers. The term frequent showers implies that nearly all areas will catch a shower, and
many places will see more than one shower (see isolated and scattered).
Frost. A generic term to cover temperatures below freezing. Where these temperatures occur describes the type of frost (air
frost, ground frost, road frost etc.) The rather loose term of ‘frost’ is rarely used in road weather forecasts without qualifying it.
Ground Frost. This term is used to describe occasions when temperatures on the ground (as opposed to in the air) fall below
freezing. The official meteorological definition uses the temperature over short mown grass. The term has little relevance to
winter maintenance, which is concerned specifically with road temperatures. The term ‘ground frost’ heard on media forecasts
(TV, radio) does not guarantee that there will also be a road frost.
Ground Heat Flux. This is a term in the heat balance at the road surface. It represents the flow of heat up from the ground to
the road surface (usually overnight) or the flow of heat from the road surface down to the road (usually during the day). The
direction of the ground heat flux can be determined by whether the depth temperature is higher or lower than the road
temperature (road temperature lower than the depth temperature implies the heat flux is from ground to road, and vice versa).
Hail. Precipitation in the form of frozen raindrops. Usually occurs in showers.
Hoar Frost. Deposition of water vapour directly as ice on to ground surfaces. The ice forms as white crystals and is usually
highly visible. Hoar frost is more common over grass than on roads. Hoar frost on roads may quickly change to clear ice under
pressure from car tyres.
Ice. A generic term for frozen water. In winter maintenance terms usually refers to clear ice on road surfaces (see Black Ice).
Icy Patches. Used in road weather forecasts to indicate ice formation in prone areas only (gutters, dips in the road surface etc.)
Icy Stretches. Used in road weather forecasts to indicate more widespread ice.
Isolated. Used in conjunction with showers, isolated showers implies that most places will stay dry, but somewhere within the
area of coverage a shower may occur (see frequent and scattered).
Instation. Generic term for Masterstation, CPU or Bureau (see Masterstation, CPU and Bureau).
Intermediate. The thermal map type that occurs on nights where cloud cover, wind speed (or both) is variable.
temperature differences tend to lie between the Damped and Extreme values (see Thermal Mapping).
Road
Latent Heat Flux. This term covers heat released or taken in by a change of state of water. The evaporation of water and the
melting of ice take in heat (and so cause cooling), whereas condensation and freezing release heat.
Long Wave Radiation. This is heat transferred from objects by infrared radiation, at temperatures around the terrestrial norm
(say between plus and minus 20 degrees Celsius). This includes the road surface itself and clouds. Radiation from the sun is in
the short wave (as the sun is much hotter).
Marginal. This describes nights where the road temperature is expected to be very close to freezing (normally within one
degree Celsius).
Masterstation. The computer system that dials the road sensors (once an hour usually), controls communications with the
weather forecast organisation and allows access by secondary masterstations or workstations. (See Bureau and Instation).
Midwinter Solstice. The day of the year when the midday sun is at its lowest elevation in the sky (in practice when incoming
solar radiation is at its weakest). The actual day varies between the 20th and 24th December. At this time, the difference
between the minimum road temperature and minimum air temperature is at its highest (road temperature around 2.2 degrees
Celsius less than the air temperature on average, in the absence of other terms).
Outstation. Another name for a road sensor.
Powder Snow. The form of snow that occurs when air temperatures are well below freezing (minus 2 degrees Celsius or less).
This form of snow is very fine (like sugar crystals), drifts very easily, but does not tend to stick to objects (no accretion). It can
be handled by snow blowers. Salt is usually less effective.
Precipitation. A general term that covers all water (or ice) that ‘falls’ from the skies. As well as rain, sleet, snow and hail it also
includes dew, hoar frost and fog.
Radar. See Weather Radar.
Radiation. A general term which covers transfer of heat from one object to the other by electromagnetic waves (infra red
radiation). All objects above absolute zero)-273.15 degrees Celsius) radiate heat, and the hotter an object is, the shorter the
wavelength of the radiation.
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Rain. Water droplets that fall from clouds. Rain takes many forms, and can be of many different intensities and durations.
Within road weather forecasts there will often be differentiation between rain and showers, the former usually referring to longer
lived but light intensity precipitation, and the latter to short duration but heavy intensity.
Relative humidity. This is the amount of actual water vapour held in a sample of air at a given temperature, divided by the
maximum amount of water that could be held in that sample of air at that temperature, expressed as a percentage. Within fog
or heavy rain, humidities may reach 100%, on a sunny, warm afternoon in summer, humidities may fall to 30%. On an average
night in winter, humidities rarely fall below 80% (which is the minimum humidity at which salt crystals will start to absorb water).
Rime. Deposition of ice from freezing fog. It is a white form of ice, similar to hoar frost, but has a finer (at times feathery)
structure. On roads, tends to be more of a problem at higher levels than lower levels.
Saturated. Air is said to be saturated when, at a given temperature, it holds the maximum amount of water vapour possible.
Any cooling below its current temperature will result in condensation. The relative humidity of saturated air is 100%.
Saturated adiabatic lapse rate. The rate at which air temperature falls with height within saturated air e.g. within fog or cloud.
It is less than the dry adiabatic lapse rate, 0.49 degrees Celsius per 100 metres or around 1.5 degrees Celsius per 100 feet.
Scattered. Used in conjunction with showers. Scattered showers imply that a wide covering of showers across an area is
expected. Most places will see at shower but one or two locations may stay dry (see Frequent and Isolated).
Secondary Masterstation.
Workstation.
A PC that the highway engineer uses to access the Master Station.
Also referred to as a
Seepage. Leakage of ground water from roadside verges. Can cause roads to become wet, when otherwise they would have
stayed dry, possibly leading to ice formation later.
Sensible heat flux. The transfer of heat between the air and the road surface. This is largely controlled by the wind.
Sleet. Partially melted snow. If precipitation becomes heavy, sleet may readily turn to snow.
Snow. A form of precipitation where tiny ice crystals bond together into flakes. Snow can be either of the Wet or Powder forms.
Solar Radiation. Incoming sunshine during the day. It is short wave radiation.
Solstice. See Midwinter solstice.
Thermal fingerprint. The temperature trace along a road surface (usually recorded by an infra-red thermometer during a
thermal mapping run). Regardless of the mean temperature of the trace, it shows the thermal characteristics of the road surface
(warm and cold spots).
Thermal map. The representation of relative variations in road surface minimum temperature for each of three weather
categories, presented in colour bands (usually of 1 degree Celsius).
Thermal mapping. The technique used to produce the thermal fingerprint of a road.
Thermal map type. Defined as damped, intermediate or extreme (see previous entries). When using thermal maps in the
forecast mode, the weather forecast organisations will send the thermal map type with the ice prediction graph.
Wash off. This occurs when rain is sufficiently heavy to remove salt solution from the road surface.
Water vapour. Water in its gaseous state.
Weather radar. A network of radars that uses a beam specifically tuned to detect rain droplets (or snowflakes) and hence infers
the location and intensity of rain reaching the surface.
Wet snow. Snow that falls with air temperature close to freezing point. It melts easily and can be very sticky (see Accretion). It
is more common in the UK than the other variant of powder snow.
Wintry. This term covers precipitation, which contains ice in one of its many variants (sleet, wet snow and hail). The term is
used extensively in media forecasts (e.g. wintry showers are expected, showers will turn wintry over hills). However, the term is
ambiguous in road weather terms and hence any precipitation containing ice will be described more fully, with likely effects on
the road.
Workstation. Typically a laptop PC that can be used by the Highway Engineer to access the CPU or bureau (see Secondary
Masterstation
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APPENDIX H
Route Plans
(Available in controlled copies)
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