Appendix A2

Detailed Response to Objector’s Comments

  1. The aim of this review was to follow the DfT guidance and set speed limits in accordance with a number of factors but primarily in line with free flowing traffic speeds.

There is no mention or requirement in the guidance to base the reduction solely on speed related accident numbers.

Speed Limits have only been changed as suggested as a result of following the review guidance.

Casualty reduction is surely a welcome ‘added benefit’ of this process.

  1. A considerable amount of time has been dedicated to carrying out the review which was started in 2006 when the national guidance was issued.
  1. Recommendations have been determined in line with national speed limit review guidance rather than any other basis.

A full analysis of all available data has been undertaken.

While measured mean speedis only one of a number of factors taken into account in setting limits, its relationship with accidents makes this an important consideration.

  1. The DfT 40% reduction in KSI target is across the board and is not scheme specific.

Casualty reduction targets in 1987 were to reduce KSIs by one-third by 81-85 baselines - a 39% fatal reduction and 45% serious reduction were actually achieved. It is anticipated that the 2010 target (40% reduction based on 1997-98 baselines ) will have been achievedwith a 42% reduction predicted.

  1. All internationally recognised experts in road safety accident investigation and prevention indicate that if accidents are addressed then casualty reduction will follow.

Road traffic accidents are constantly monitor and analyse road traffic accidents, either by looking at accidents occurring in clusters, on routes, or across areas.

  1. The speed limit review scheme proposals represent good value for money in accident reduction terms and cover a large part of the highway network in one go.

Normally £30k would not be enough to treat one accident hotspot and would possibly only save 1-2 injury accidents just at one location.

  1. Speed is a factor in 19% of KSIs which is a significant percentage, with a figureof 44% for motorcycle users.

DfT figures indicate that 25% of all fatals nationally involve speed as a contributory factor.

  1. The underlying aim of managing speeds is to achieve a ‘safe’ distribution of speeds which reflects the function of the road. This will reduce ‘bunching’ and shunt accidents that can occur as drivers speed up then have to slow down again as they approach the end of the queue ahead.
  1. The TRL research quoted was referred to in the report as what reasonably could be expected in terms of casualty reduction – 15% and 2-3mph reduction in average speeds.

It is not the sole basis for the review, as described in this report.

Predicted casualty reductions, if achieved, would indicate approx. £300,000 would be saved annually.

  1. The British Medical Journal studies compare hospital data with stats 19 data and appear to show under reporting of road injury collisions; however DfT analysis has shown that there is often a lot of duplication of casualty numbers when looking at hospital returns data.
  1. The speed limit guidance gives no specific direction as to how many readings are required, or indeed how or when these should be undertaken.

Where possible there has been a minimum of 400 speed readings, not just spot monitoring. On Dorset Way/Canford Way for example, it is not practical to cut loops, put out tubes, or use radar boxes as these don’t cover both lanes.

  1. According to the analysis 62mph is recorded as the mean speed on Dorset Way, and below 50mph on Canford Way.

The objector has looked through several weeks’ data in order to find the highest possible mean speed figures, over a weekend or at night, whereas the figure used in this report is free flowing daytime weekday figures.

  1. As the original TAG reportreferred to then according to the review guidelines,a 60mph limit could be set on Dorset Way. However as stated this would be unusual for a dual carriageway and would require specific DfT authorisation.

Furthermore the guidance also indicates that all urban dual carriageways should have a maximum speed limit of 50mph.

  1. Two out of the six fatals in 2008 occurred on Dorset Way.

Nationally 38% of fatals occur on roads with speed limit > 30mph.

The Dorset Way accident rate iscurrently 31.5 injury collisions per 100m veh km for all categories of casualty, which is below the national average. However of these 20% of these are KSIs which is above the national average.

Although there is no direct pedestrian access to the road and there are few slip roads (from Yarrow Road and Oakdale Road) there are nevertheless a significant number of injury accidents and damage-only crashes which have occurred either at the roundabouts or in the vicinity of the slip roads.

  1. Any additional enforcement required would have resource implications for the police and could not therefore be guaranteed. However the suggestion is that consideration be given to time over distance type enforcement to deal with any significant non-compliance in future. Consideration may also be given to illuminated vehicle activated speed signs or warnings of specific road safety hazards.
  1. The speed limit change on Holes Bay Road was effected before national guidance 1/06 was issued. It was changed in response to a number of fatals and serious accidents on the road, and delivered both a reduction in mean speeds and accidents. The speed limit reduction from NSL ( 70mph ) to 50 mph achieved an average speed reduction from 68 to 44mph, and an associated reduction in accidents of 23% ( against a predicted drop of 20% ).

Accidents on roundabouts should not be excluded from any analysis as the posted speed limit would have been a factor in all crashes wherever they occurred.

  1. Driver Awareness Coursesactually cover a range of driving situations and concentrate on aspects such as hazard perception, sign recognition etc.
  1. One of many statements made by the objector which appears to be factually based but is actually largely reproduced on anti-speed camera websites.
  1. Safety of pedestrians is always a concern and this crossing will be fully risk assessed once the proposed changes have been implemented.