SPEED
MANAGEMENT STRATEGY
Final Draft
November 2009
- / Glossary of Terms / 41.0 / Introduction
1.1 / Why review the Speed Management Strategy? / 6
1.2 / What is the Speed Management Strategy? / 6
1.3 / Speed Management Policy / 7
1.4 / Who is the strategy for? / 7
1.5 / Who is responsible for the speed management strategy? / 7
2.0 / Setting Speed Limits
SETTING SPEED LIMITS KEY CRITERIA (C1 – C6) / 8
2.1 / Speed Limit Framework / 8
2.2 / Proposed Speed Limit Thresholds / 9
2.3 / Hertfordshire Speed Limit Framework / 10
2.4 / A & B road speed limit review / 10
2.5 / Police & Speed Management Group support / 10
2.6 / Traffic Regulation Orders / 11
SETTING SPEED LIMITS FREQEUNTLY ASKED QUESTIONS (Q1) / 11
3.0 / Selection and Funding
FUNDING AND SELECTION KEY CRITERIA (C7 – C12) / 13
3.1 / Introduction / 13
3.2 / Local Transport Plan Targets / 13
3.3 / s106 contributions / 14
3.4 / External contributions / 14
3.5 / Hertfordshire Highways Discretionary funding / 14
3.6 / HertfordshireCounty Council Locality Budgets / 15
3.7 / Potential funding for 20mph limits and zones / 15
3.8 / Speed Management Group / 15
4.0 / Traffic Calming Measures
4.1 / Introduction / 16
4.2 / Before Traffic Calming Measures are considered / 16
4.3 / Maintenance / 16
4.4 / Traffic Calming Measures Table / 17 – 29
TRAFFIC CALMING KEY CRITERIA TABLE (C13 – C63) / 17 - 29
TRAFFIC CALMING FREQEUNTLY ASKED QUESTIONS (Q2 – Q6) / 30 – 31
5.0 / Speed Enforcement
SPEED ENFORCEMENT KEY CRITERIA (C64 – C66) / 32
5.1 / Introduction / 32
5.2 / The Role of the Police / 32
5.3 / The Role of the County Council as Highways Authority / 33
5.4 / The Role of the Safety Camera Partnership / 33
SPEED ENFORCEMENT FREQUENTLY ASKED QUESTIONS (Q7 – Q9) / 34
6.0 / Safety Cameras
SAFETY CAMERAS KEY CRITERIA (C67) / 35
6.1 / Introduction / 35
6.2 / Criteria for site selection and implementation / 35
6.3 / Current Technology / 35
6.4 / Emerging Technology and use in Hertfordshire / 36
SAFETY CAMERAS FREQUENTLY ASKED QUESTIONS (Q10 – Q11) / 36
7.0 / Education, Training and Publicity
EDUCATION AND PUBLICITY KEY CRITERIA (C68) / 37
7.1 / Education / 37
7.2 / Training / 37
7.3 / Publicity / 37
EDUCATION AND PUBLICTY FREQUENTLY ASKED QUESTIONS
(Q12 – Q15) / 38
Appendices
App 1 / Hertfordshire Speed Limit Framework / 40
App 2 / Hertfordshire Speed Enforcement Guide / 42
App 3 / Criteria for Safety Camera Site Selection and Implementation / 43
- DEFINITIONS -
85th percentile speed / The speeds at or below 85% of all vehicles are observed to travel under free flowing conditions. This is a nationally recognised method of assessing traffic speeds.Hazardous Site / A site that meets one of a number of injury collision criteria.
Local Transport Plan / Statutory document which sets out the overall objectives and targets for improving transport in the County.
Local Transport Plan Objective / The Local Transport Plan has eight objectives under these headings – Safety, Congestion, Accessibility, Air Quality, Quality of Life.
Local Transport Plan Target / The Local Transport Plan contains twenty two targets to be achieved when the current plan expires. There is funding available to meet these targets. Speed management measures can assist in meeting the targets. Refer to section 3.
Mean speed / The average speed at which all vehicles travel at.
STATS 19 form / The Department for Transport compiles data on personal injury road accidents, resulting casualties, and the vehicles involved. The Police fill in this form for each accident occurring on the public highway, and which become known to them within 30 days.
Urban Transport Plan / Transport strategy for specific town(s) within Hertfordshire.
- ACRONYMS -
ACPO / Association of Chief Police OfficersDfT / Department for Transport
HADECS / Highways Agency Digital Enforcement Camera System
KSI / Killed and Seriously Injured
LTP / Local Transport Plan
(see definition on previous page)
NMU / Non-motorised user
PTU / Passenger Transport Unit
RTC / Road Traffic Collisions
S106 / Funding negotiated from developers to mitigate the impact of the development
SID / Speed Indicator Device
SMG / Speed Management Group
TAL / Traffic Advisory Leaflet
(produced by the Department of Transport)
HQ TM / Head Quarters Traffic Management
UTP / Urban Transport Plan
(see definition on previous page)
1.1 / Why review the Speed Management Strategy?
1.1.1
1.1.2
1.1.3
1.1.4 / The County Council’s previous Speed Management Strategy was adopted in July 2005. Since this time, a number of new government circulars and guidance documents have been published. It is therefore appropriate to review the strategy. Key elements have been extracted, and areas highlighted where the County Council has taken a departure from this guidance. The key document that has been considered is the DfT circular 1/06 ‘Setting Local Speed Limits.’
The County Council and Hertfordshire Constabulary receive many requests in relation to speed management. These can be addressed through a number of ‘tools’:
- Speed enforcement
- Schemes and measures
- Education
The revised strategy should help both members and officers promote measuresand enforcement that deliver against agreed strategic policies, and can be measured against one of the objectives and as set out in the second Local Transport Plan (2006/07 – 2010/11).
1.2 / What is the Speed Management Strategy?
1.2.1
1.2.2 / The purpose of the speed management strategy is to set out:
- How speed management schemes are selected and funded.
- A consistent approach to setting speed limits based on the function and nature of the route.
- A consistent approach to the implementation of speed management traffic calming measures.
- The role of the Police and County Council as Highways Authority in relation to speed enforcement.
- The key criteria for the selection of safety camera sites.
- Outlines education and publicity programmes.
1.3 / Speed Management Policy
1.3.1
1.3.2
1.3.3
1.3.4
1.3.5 / Section 6.13 in the Local Transport Plan sets out the speed management policy which informs the speed management strategy.
The policy statement outlines which of the Local Transport Plan objectives and targets the speed management policy will contribute towards.
This speed management policy states:
“The County Council will ensure that speed limits are introduced and reviewed in a manner consistent with the current government guidance. Exceptions to usual practice will be set out in the Speed Management Strategy which will be subject to periodic review.
The introduction of speed management measures will only be considered where it can be demonstrated they meet and contribute to the:
- Speed Management Strategy including the key criteria
- Local Transport Plan Objectives
Each area of speed management is discussed and key criteria set out which meet both the speed management policy and government guidance.
Where further clarity is required beyond the guidance, in a certain area this is stated and objective criteria given. Only in exceptional circumstances will departures from DfT guidance and circulars be considered.
1.4 / Who is the strategy for?
1.4.1 / It is intended that the strategy will be read and used by:
- The Hertfordshire Highways Design Team
- Officers with a professional interest in speed management
- Local Members
- Hertfordshire Constabulary
1.5 / Who is responsible for the strategy?
1.5.1
1.5.2
1.5.3 / The County Council as Highways Authority is responsible for the management of speed on all public roads in Hertfordshire (except those maintained by the Highways Agency).
The Police are responsible for the enforcement of speed limits.
The strategy has been developed in partnership between Hertfordshire County Council, as Highway Authority, and Hertfordshire Constabulary.
KEY CRITERIA - Setting Speed Limits
C1 / The County Council will set speed limits using the Hertfordshire Speed Limit framework.
C2 / An assessment of the environment must be made to confirm that a speed limit is appropriate for the road.
C3 / The mean and 85th percentile vehicle speeds must not exceed those stated in the Proposed Speed Limit Threshold table for the specified limit.
C4 / 20mph speed limits will only be considered where the 85th percentile speeds are 25mph or below.
C5 / If there is not a consistent relationship between the 85th percentile and mean speeds, the appropriateness of the existing limit will be reconsidered.
C6 / The Speed Management Group will assess all speed limit change requests to ensure consistent application of the key criteria.
2.1 / Speed Limit Framework
2.1.1
2.1.2
2.1.3
2.1.4 / Hertfordshire’sapproachtotheapplicationofspeedlimitsmustbeconsistentifitistobeunderstoodandcompliedwithbythemajorityofdrivers.TheapplicationofspeedlimitsshouldalsobeconsistentacrossthecountryandthiswasrecognisedbytheGovernmentinitsRoadSafetyStrategy“Tomorrow’sRoads–SaferForEveryone”publishedin2000.
TheHertfordshire Speed Limit Frameworkislargelybasedonexistingguidelinesforthesettingofspeedlimitsandisintendedtoprovideageneralguideforspeedlimitselection. The key government guidance documents are:
- DfT Circular 1/06 – Setting Local Speed Limits
- TAL 2/06 – Speed Assessment Framework
• Is the environment suitable for the speed limit being considered?
• Existing 85th percentile speeds and mean speeds.
• The level of use by both motor vehicles and vulnerable users.
•Anyspeedrelatedcollisionhistory.
Speedlimitsshouldbeevidence-led,self-explainingandseektoreinforcepeople’sassessmentofwhatisasafespeedtotravel.Theyshouldencourageself-complianceandnotbeseenbydriversasbeingatargetspeedatwhichtodriveinallcircumstances.
2.2 / Proposed Speed Limit Thresholds
2.2.1
2.2.2
2.2.3
2.2.4
2.2.5
2.2.6
2.2.7
2.2.8
2.2.9
2.2.10 / Thecurrentguidanceforsettinglocalspeedlimitsstatesthat traffic authoritiesshouldcontinuetoroutinelycollectandassessbothmeanand85thpercentilespeeds,butthatmeanspeedsshouldbeusedasthebasisfordetermininglocalspeedlimits.
Italsostatesthatwherethereisnotaconsistentrelationshipbetweenthetwo,itwillusuallyindicatethatdrivershavedifficultyindecidingtheappropriatespeedfortheroad.This suggeststhatabettermatchbetweenroaddesignandspeedlimitisrequired. Insuchsituationsitmaybenecessary to consider the appropriateness of the limit.
Whenreviewingaspeedlimitforasectionofroad,itwouldseemappropriatethatspeedlimitreductionsshouldonlybeconsideredwherethe85thpercentilespeedsarelessthanthethresholdatwhichenforcementwouldberequired.Otherwiseitwouldplaceadditional enforcement pressureon the Police. For example, 85th percentile speeds should not be above 35mph if considering lowering the limit to 30mph.
TheAssociationofChiefPoliceOfficers(ACPO)setguidelinesforthethresholdatwhichenforcementactionshouldbetaken.Thesecanbeseeninthe Proposed Speed Limit Thresholds table below whichshowsthemaximumpermissiblemeanand85thpercentilespeedthataretobeusedwhenconsideringaspeedlimit.
Proposed Speed Limit Thresholds Table
ProposedSpeedLimit / MaximumMeanSpeed / Maximum85thpercentilespeed(ACPO)
20 / 24
30 / 29 / 35
40 / 39 / 46
50 / 49 / 57
60 / 59 / 68
70 / 69 / 79
Whenanalysingtrafficspeeddata,itisimportanttolookatthespeedsthatoccurunderfreeflowtrafficconditions,andthereforethe12 houror24 houraverage85thpercentilespeedsmaynotbeappropriate. Itmaybenecessarytoexcludepeakhourdataascongestionmayhaveadramaticeffectontheresults.
Itisalsoimportantthatspeedlimitsshouldnotbereviewedinisolation,anditisbestpracticetoreviewthewholelengthoftheroute.
20mphSpeedLimits
Whenconsideringa20mphspeedlimitcurrentguidancesuggeststhatroadsthatarebeingconsideredshouldhavemeanspeedsof24mphorbelow. For Hertfordshire the 85th percentile speeds will be used to ensure that the level of non compliance does not trigger excessive requests for enforcement.
Takingintoaccountthepointsabove,20mphspeedlimitswillonlybeconsideredwherethe85thpercentilespeedsare recorded at 25mph or below. Once20mphsignsareintroduceditisacceptedthatthesignageshouldhaveaspeedreducingeffectofapprox1mph,whichwouldbringthespeedsdowntotherequiredlevelof24mph.
20mphZones
Withregardto20mph zones,theseshouldbedesignedwithselfenforcingspeedreducingmeasurestoensurethatthemaximum85thpercentilespeedis24mph, or less once they are implemented.
Allotherspeedlimits
SpeedlimitsshouldbeassessedfollowingtheguidancewithinDfTCircular01/2006-Settinglocalspeedlimits,andusingtheSpeedassessmentframeworksetoutin traffic advisory leaflet 2/06.
2.3 / Hertfordshire Speed Limit Framework
2.3.1 / The Hertfordshire Speed Limit Framework provides a guide to assist in speed limit selection, particularly in assessing whether the environment or nature of a particular road is suitable for a specified limit. See Appendix 1 – Hertfordshire Speed Limit Framework for further detail. Any limit changes must be considered by the Speed Management Group – see section 3.8.
2.4 / A & B Speed Limit Review
2.4.1 / The County Council will be carrying out a speed limit review on all its A & B roads to assess if the limits are correct for the environment. This review will be carried out using the Hertfordshire speed limit framework and will be completed by 2011.
2.5 / Police & Speed Management Group Support
2.5.1 / Proposed speed limits should be supported by the Police. If the Police are not supportive of a proposal it should be reconsidered. Changes will also be assessed by the Speed Management Group, of which the Hertfordshire Constabulary are a member – see section 3.8 for further detail.
2.6 / Traffic Regulation Orders
2.6.1 / Any change in speed limit will require a traffic regulation order to make it legally enforceable. All orders have to be advertised allowing the public an opportunity to comment or object.
FREQUENTLY ASKED QUESTIONS
Setting Local Speed Limits
Q1 / What are 85th percentile and mean speeds?
85th percentile speeds are the speeds at or below 85% of all vehicles are observed to travel under free flowing conditions. This is a nationally recognised method of assessing traffic speeds.
Meanspeeds are the average speeds that all vehicles travel at.
KEY CRITERIA – Selection & Funding
C7 / LTP Funding – Speed Compliance Target:
To access funding from this Local Transport Plan target
- The environment must be suitable for a 30mph speed limit.
- Recorded 85th percentile vehicle speeds on weekdays must be at least 35mph (following ACPO threshold speeds).
- The scheme will be selected by the Speed Management Group.(see section 3.8).
C8 / LTP Funding - Casualty Reduction:
To access funding from this Local Transport Plan target a site with a speed management issue would need to be a high priority on the Hazardous Sites ranking system to access funding from this target.
C9 / LTP Funding – Mode Share to School:
To access funding from this Local Transport Plan target a site with a speed management issue would need to be a high priority on the Mode Share to School ranking list to access funding from this target. The scheme would also need to be selected by the Mode Share to School Target Delivery Group.
C10 / LTP Funding – Increasing cycling trips:
To access funding from this Local Transport Plan target a site with a speed management issue would need to deliver an increase in cycle trips. The scheme would also need to be selected by the Increasing Cycling Trips Target Delivery Group.
C11 / LTP Funding – Quality of Life:
Schemes and measures being funded through other LTP targets can access funding from this target to provide “quality of life” improvements.
C12 / The Speed Management Group will consider and assess all the schemes which are put forward in developing Urban Transport Plans that make a contribution towards the speed compliance target.
3.1 / Introduction
3.1.1
3.1.2 / Speed management schemes and measures can be funded through a number of sources. These are:
- The Local Transport Plan Target Programmes
- Section 106 Developer funding
- External funding (eg. Borough, District & Parish Councils, Grants)
- Hertfordshire Highways Discretionary funding
- Hertfordshire County Council Locality budgets
3.2 / Local Transport Plan Targets
3.2.1
3.2.2
3.2.3
3.2.4
3.2.5
3.2.6 / The primary funding source for speed management schemes and measures is government Local Transport Plan capital funding. The plan has twenty two different targets which have funding attached to them. Listed within this section are the most relevant targets / funding streams for the implementation of speed management measures. To be selected and funded by a Local Transport Plan target a scheme or measure must demonstrate how it meets the set target criteria. If selected, it will also be subject to the recommendations made in a feasibility study and Safety Audit.
The County Capital Funding Programme sets out the annual spending programme for all Highways and Transport schemes and projects.
Speed Compliance:
This is the key Local Transport Plan target for speed management measures. The target is to increase compliance of weekday traffic with the 30mph speed limit. Therefore funding can only be used on roads where the speed limit is 30mph. So this can not be used to fund 20mph zones for example. See paragraph 3.7 for potential funding sources for 20mph limits and zones.
To assess whether a scheme is suitable to meet this target the following must be assessed:
- The environment must be suitable for a 30mph speed limit.
- Recorded 85th percentile week day vehicle speeds must be at least 35mph (following ACPO threshold speeds – see table in paragraph 2.2.4)
Casualty Reduction:
There are various targets to reduce the number of casualties on Hertfordshire roads. Recorded collision data is collected regularly and is used to help prioritise sites for measures through the annual Hazardous Sites ranking system. Those sites with the highest priority are then selected for further investigation and potential treatment. Any site with a speed management issue would need to be a high priority on the Hazardous Sites ranking system to access funding from this target. This is reviewed annually and is available on request by contacting .
Mode Share to School:
The main funding source for schemes outside or near schools is through the Mode Share to School target. Any speed management scheme or measure funded by this target will only be considered if it results in an increase of children walking or cycling to school. The Mode Share to School Target Delivery Group has the responsibility of selecting schemes on an annual basis which will most effectively meet this target.
A majority of this funding is used for the ‘Safer Routes to School’ programme. All schools across the County are prioritised each year.
Increasing Cycling Trips:
There is a Local Transport Plan target to increase the number of cycling trips. Speed management schemes can be considered by the Increasing Cycling Target Delivery Group if they deliver an increase in cycling trips. The target delivery group will select schemes which most effectively deliver against this target.
Quality of Life:
Quality of Life funding can be used to provide enhancements to existing LTP funded schemes. For example, a traffic calming scheme funded through the Speed Compliance target may use enhanced materials funded through the Quality of Life target.
3.3 / s106 Funding:
S106 funding obtained through developers contributions can be used for speed management schemes and measures if:
- It is appropriate to the wording of the agreement, and
- The Environment Department Highways and Transport s106 Guidelines have been followed.
3.4 / External funding (eg. Borough, District, & Parish Councils, Grants)
Where possible the County Council will work with other local councils to joint fund speed management schemes and measures which meet the objectives of both parties.
3.5 / Hertfordshire Highways Discretionary funding
Discretionary funding can be used towards speed management schemes and measures, as long as the criteria in the strategy are followed. This is subject to agreement of the District or Borough Highways Joint Member Panel.
3.6 / HertfordshireCounty Council Locality budgets
Locality budgets can be used towards speed management schemes and measures, as long as the key criteria in the strategy are followed.This is subject to agreement of the local member.
3.7 / Potential funding for 20mph limits and zones
The definitions and criteria for the implementation of a 20mph limit or zone should be considered (see section 4.4) alongside the availability of funding. Listed below are potential funding sources for 20mph limits and zones.
- LTP Target: Casualty Reduction (see section 3.2.3).
- LTP Target: Mode Share to School (see section 3.2.4).
- LTP Target: Increasing Cycle Trips (see section 3.2.5).
- LTP Target: Quality of Life (see section 3.2.6).
- S106 funding (see section 3.3).
- External Funding (see section 3.4).
- Hertfordshire Highways Discretionary Funding (see section 3.5).
- Hertfordshire County Council Locality Budgets (see section 3.6).
3.8 / Speed Management Group:
3.8.1
3.8.2
3.8.3 / The Speed Management Group (SMG) has been established to ensure the key criteria within the Strategy are being followed and consistently applied. This includes:
- Selection of LTP schemes and projects which will deliver effectively against the speed compliance target.
- Checking progress on the speed compliance target.
- Considering any issues arising from speed management schemes.
- Considering all schemes put forward in developing Urban Transport Plans which help deliver the speed compliance target.
- Assessing all speed limit change requests.
- Transport and Programmes Unit, Hertfordshire Highways
- Design Team, Hertfordshire Highways
- Road Safety Unit, Hertfordshire County Council
- Hertfordshire Constabulary