The quest for better evidence in planning transport infrastructure: when will we explore facts instead of following big numbers?

By John Dales

In transport terms, there is, of course, a reasonable body of evidence suggesting strongly that creating more road capacity is often just as pointless an exercise. Traffic growth predictions can simply be big numbers that bludgeon common sense into submission. Yet recent UK reports, The Government's Action for Roads and London’s Roads Task Force, both seem to accept dubious 'estimates' whilst failing to procure real facts or robust evidence