The government has proposed raising the motorway speed limit to 80 mph. It says that our motorways have become safer as cars have become safer and that law abiding citizens have lost respect for the 70 mph limit. It also says the economy would receive a boost if our motorway speed was higher as in competitors like France and Germany. The government believes that the rise in crashes would not be significant and acknowledges some motorways have engineering weaknesses. This report looks at the evidence including fresh analysis of the Foundation’s unique crash and engineering data. The findings show at least half of fatal and serious crashes on motorways result from either vehicles running off the road or from shunts. Widespread faults in roadside engineering double the risk of serious run-off crashes. The number of shunt crashes rise exponentially with traffic flow. Half of English motorways carry more than 85,000 vehicles daily. Busy motorways need electronic control to help avoid shunts and pile-ups. The M42 and M25 are rare exceptions which have investment in electronic control allowing variation in permitted speed - with strong enforcement - depending on traffic flow, incidents and weather. The speed evidence suggests that those who want to drive at 80 mph on English motorways largely already do so if low traffic density permits. Opinion surveys show that the public do not support “80 means 90”. If government wants to trial 80 mph then it must be “enforced 80”. On busy English motorways, 80 mph can only make sense in good weather when traffic is light - and trial 80 mph sections must have electronic control. The costs associated with the 800 serious motorway road crashes annually is £0.4 bn — double that if traffic delays at crash sites are counted. High return, affordable adjustments to safety engineering are quick and certain ways to boost GDP - the best buys are "run-off" protection (such as installing missing safety fences) and electronic controls on busy motorways. England’s motorways may be intensely used but can become more reliable and a world class safe system. (Author/publisher)
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