8 June, 2013

Now there’s evidence – fewer accidents with less traffic regulation

Many might understand that governmental regulatory authorities have difficulty coming to terms with ideas that less regulation result in better outcomes. But, in road traffic regulation, supporting evidence for this idea is almost irrefutable.

Among the first to implement this idea is Dutch traffic engineer Hans Monderman, who radically challenged criteria used in evaluating road planning. Historically, road planners were inclined to plan safer environments using more regulation. But Mr Monderman argued this was the wrong approach – holding instead that the right way to go is with less regulation, placing greater responsibility on those actually using the roads. Also, rather than separate auto traffic from bicyclists and pedestrians with more signs, lines and traffic lights—he felt that road designers should integrate all these groups in traffic to the extent possible. Or, as Mr Monderman expressed it himself: “Traffic engineers have this boring habit of always trying to resolve traffic issues by adding more of everything. But I feel the better approach is to ask yourself what can be removed.”

When assigned to design a roundabout in the small Dutch town of Drachten (pop. 40,000) in 2001, he implemented these ideas. This was not a low volume intersection, despite the town’s size, where over 18,000 motor vehicles, and 5,000 bicyclists pass the now downscaled roundabout daily. Mr Monderman replaced road signs and traffic lights with an ingenious design that forces all users to communicate with each other as they pass through. Now the concept has its own engineering term – ‘Shared space’.

Local Dutch traffic authorities have closely monitored the statistics for this intersection, especially the number of accidents. And, they found that accidents have decreased from an average of 10.25 per year to just 3.5, after the roundabout was redesigned – a reduction of nearly 70%. Further, the number of personal injuries from these accidents decreased from an average of two every year to just 0.33. This is an impressive achievement, especially considering that traffic volume at the intersection has increased 30%.

To this end, several systematic tests have been conducted in Great Britain, where existing traffic lights have simply been shut off at randomly selected times. And, the findings were unexpectedly positive, in every respect. Engineers found that traffic flowed much better and the number of accidents decreased to nil. There’s more to read here.