20mph Speed Limit Trial Warrington Borough Council Mark Tune Traffic Management & Road Safety Manager
Benefits of reduced speed Reduced number and severity of accidents More cycle friendly environment More pedestrian friendly environment Wider travel options Greater ownership of streets and public space by residents
Historically 20mph speed limits have previously been introduced as part of traffic calming schemes on an area wide basis, using physical measures such as speed humps, cushions and chicanes. 20mph Speed Limits had been introduced school frontages although failed to reduce average vehicle speeds.
Why Pilot? Changes in DfT guidance on the use of 20mph speed limits. Portsmouth City Council decision. Diminishing returns Cost of Borough wide implementation circa. 740k Local and National pressure groups
The Proposed Trial of 20mph Speed limits
The Trials Three pilot areas were launched on 14th February 2009 to run for an 18 month period, the maximum length of time permitted for the experimental Traffic Regulation Orders (TROs) required to make the 20mph speed limits enforceable. Town Centre having a history of vulnerable road user casualties although a significant proportion associated with the night time economy. Orford Area - (Long Lane/ Sandy Lane/ Northway Area) is contained within a large residential area, which has a history of vulnerable road user casualties despite some physical traffic calming measures. Park Road having relatively few injury collisions although an unusually high proportion involved serious injury to pedal cyclists.
Town Centre Area
Orford Area
Park Road Area
Data Capture 183 roads included in the pilot areas with 25 monitoring stations. Collision / casualty data Traffic speed and flow Level of cycle usage Effects on vehicle emissions Public Perception of 20mph speed limits
Traffic Surveys Stage Stage 1 Before (June 2008) Stage 2 - three months into the pilot (April 2009 ) Reason establish the baseline for measurement of change To reflect a change in behaviour that may be due to the change in environment and significant level of publicity. Also to provide an understanding at project end if any changes had been sustained. Stage 3 9 to10 months into the pilot (November 2009 ) To understand if any initial reductions had been sustained along with further changes as a result of an enforcement threat. Undertaken in conjunction with increased Police activity and engagement days run by WBC Road Safety Officers, Cheshire Fire and Rescue, and Cheshire Constabulary. Stage 4 - immediately prior to the end of the pilot (July 2010 ) To understand if any changes in road user behaviour were still evident after a significant period of limited supporting activity to the 20mph speed limits.
Public Perception Survey It was important that the communities and road users of Warrington were not aware of the proposed trials whilst before data was being collected, as this might have impacted on their behaviour. Perception surveys were delivered to 100 random addresses in each of the 3 study areas. The surveys were sent out in three stages: 1. Before the study began - February 2009; 2. During the study - November 2009; and 3. At the trial period - August 2010.
Engagement The methods of engagement with Public included: A Public Perception Survey; Newspaper adverts; Distribution of an information Leaflet; Various Consultation Events; Driver Engagement Days; Development of a Website information page; and Creation of a Web Forum to facilitate debate.
Results - Traffic Flows Overall Traffic Flows Reduced by an Average of 2678 Vehicles per Week per Road, equating to 11% from the Baseline Traffic Flows. Several Town Centre Roads were adversely affected due to Temporary Traffic Management for the end of trial survey readings.
Results - Speed Reduction Before Average Speed = 24.9092mph After Average Speed = 23.456mph Post Trial Overall Speed Reduction = 1.4532mph Reduction
Speed (mph) Speed Reduction Town Centre Average Vehicle Speeds 22.6 22.4 22.2 22 21.8 21.6 21.4 21.2 21 20.8 20.6 20.4 June 2008 April 2009 Nov 2009 July 2010 Date Vehicle Speeds
Speed (mph) Speed Reduction Orford Area Average Vehicle Speeds 27 26.5 26 25.5 Vehicle Speeds 25 24.5 24 June 2008 April 2009 Nov 2009 July 2010 Date
Speed (mph) Speed Reduction Park Road Area Average Vehicle Speeds 28.5 28 27.5 27 26.5 26 25.5 25 24.5 24 23.5 June 2008 April 2009 Nov 2009 July 2010 Date Vehicle Speeds
Qualifying Collisions
Collision Comparison Collision Data Before During Trial Variance Collisions Casualties Collisions Casualties Collisions Casualties Fatal 0.0 0.0 0.0 0.0 0.0 0.0 Orford Park Road Town Centre Serious 3.5 3.5 2.0 2.0-1.5-1.5 Slight 24.6 25.5 15.0 21.0-9.6-4.5 Total 28.2 29.0 17.0 23.0-11.2-6.0 Fatal 0.0 0.0 0.0 0.0 0.0 0.0 Serious 0.0 0.0 0.0 0.0 0.0 0.0 Slight 4.4 5.3 2.0 2.0-2.4-3.3 Total 4.4 5.3 2.0 2.0-2.4-3.3 Fatal 0.0 0.0 0.0 0.0 0.0 0.0 Serious 1.8 1.8 3.0 3.0 1.2 1.2 Slight 19.4 22.9 18.0 34.0-1.4 11.1 Total 21.1 24.6 21.0 37.0-0.1 12.4 All Area Total 53.7 59.0 40.0 62.0-13.7 3.0
VRU Collisions 18months Before Trial 18months During Trial Cyclists Pedestrians Cyclists Pedestrians Vulnerable User Collisions Fatal Serious Slight Total Fatal Serious Slight Total Total All Fatal Serious Slight Total Fatal Serious Slight Total Total All Orford Area 0 0 8 8 0 3 6 9 17 0 1 5 6 0 1 4 5 11 Town Centre 0 1 2 3 0 1 9 10 13 0 1 2 3 0 1 4 5 8 Park Road Area 0 0 1 1 0 0 2 2 3 0 0 0 0 0 0 2 2 2 Total 0 1 11 12 0 4 17 21 33 0 2 7 9 0 2 10 12 21
Perception Results Would you like to see the 20mph speed limit become permanent in your area? No 23% If the 20mph speed limit became permanent, would it encourage you to walk or cycle more? Yes 77% Yes 27% No 73%
Perception Results Will there be a positive effect on driver behaviour if all residential roads in Warrington became 20mph? No 46% Yes 54% Do you think there has been a reduction in speed since the introduction of the 20mph speed limts? Yes 19% Sometimes 40% No 41%
Driver Engagement Days
Driver Engagement Days Not relevant on this road Very slow Ridiculous 30mph is slow enough for the town centre Unrealistic on this road, no real hazards Brilliant idea Good
Experience during the pilot Initial feedback and debate in the community Critical comments Park Road single road speed limits not well received Difficult for local politicians Campaigners concerned pilots would not reflect Borough wide roll out
Pilot Costs Surveys 6,500 each time Signage 83,000 TROs & Publicity 10,000 TOTAL 119,000
Conclusions from the Pilots Did pilots effectively model a Borough wide use of 20mph speed limits? Was the method of modelling statistically reliable? Were the perception surveys and engagement results reliable? Reductions in average vehicle speed and significant reductions in collisions appear to be related. Are the benefits evidenced likely to be sustainable?
Political Decisions Positive results reported to Executive Board 18 th October 2010. Agreed to principle of the long term roll-out of 20mph speed limits subject to the availability of funding and LTP3 prioritisation. Authorised officers to consult on the intention of making permanent traffic Regulation Traffic orders in the pilot areas with the exception of Park Road and A50 Long Lane. To undertake further work to develop a road hierarchy, assessment criteria, and a prioritisation process.
Current Status Pilot areas made permanent 15 th April 2011 Cost 25k Continue monitoring of Permanent 20mph speed limits. Overview & Scrutiny working group to is to be established to work on the mechanisms for roll out and report back to the Executive Board.
Questions? Contact details mtune@warrington.gov.uk Telephone 01925 442695 Reports available at : http://www.warrington.gov.uk/home/transport_planning_and_environment/roads/collision_i nvestigation/