Helen McArdle: Average speed cameras behind ‘statistically significant’ drop in fatal and serious crashes
TOMORROW will be two years to the day since average speed cameras were switched on along a 99-mile stretch of the A9 between Dunblane and Inverness.
Statistics marking the halfway point of the three-year evaluation appear to indicate that the scheme is achieving its desired effect: fewer road deaths, fewer injuries, and a fall in drivers caught speeding.
In the first 18 months after the cameras were activated on October 28 2014, eight people were killed on the route compared to the previous 18-month average of 12. Meanwhile, the number of serious injuries between Dunblane and Inverness fell by 73 per cent from 30 to eight and the number of drivers speeding on what was once Scotland’s deadliest road was down from one in three to one in 10.
The results have gradually undermined the arguments of those who bitterly opposed the scheme by claiming that artificially slowing the traffic, particularly heavy-goods lorries, would backfire by encouraging drivers into risky overtaking manoeuvres – thus increasing the number of crashes and casualties.
The evidence from the A9 example appears to be mirrored across the UK and, if anything, the rollout of average speed camera initiatives is only set to accelerate.
Earlier this month, the RAC Foundation released its own research on the effectiveness of such schemes and concluded they were responsible for “highly significant reductions” in traffic collisions, especially those “of a high severity”.
Its analysis of 25 permanent average speed camera sites installed across Britain between 2000 and 2015 – including the A9 scheme and Scotland’s first average speed camera initiative on the A77 from Ayr to Stranraer – found that they were associated with a 15-46 per cent reduction in fatal and serious collisions. The mean reduction was “a large and statistically significant” 36.4 per cent.
Personal injury collisions also fell by between nine and 22 per cent.
The report found “no evidence for the existence of any optimum speed limit that leads to the installations achieving greater collision reduction”. In other words, the cameras appeared to be equally effective in areas where the speed limit was 40mph as 60mph.
It is the most comprehensive study to date on the effectiveness of average speed cameras in improving road safety, with the bulk of previous research tending to focus on spot speed cameras and mobile units.
By 2015, 183 miles of carriageway across Britain – more than ever before – were under surveillance from average speed cameras.
They are only likely to increase in number as evidence of the benefits mount and the technology becomes ever-cheaper.
The RAC Foundation report notes that installing permanent average speed cameras cost as much as £1.5 million per mile in 2000. By 2015, it had tumbled to just £100,000 per mile.
Road casualties in Scotland are already at a record low, in line with wider trends in the developed world linked to factors such as better road engineering, vehicle design, driver education and improved trauma care.
If artificial intelligence gradually replaces humans – and human error – behind the wheel, as many predict it will with the rise of driverless cars, fatal and serious crashes will become increasingly rare.
But until then, camera technology appears to offer us a major tool to make our roads much safer.