Trunk road investment, environmental costs and bureaucracy

This paper provides evidence of wide divergences between forecast and out-turn traffic flow, this being a principal cause of erroneous investment decisions in the road building programme of the UK. Such decisions are in part argued to be the consequences of allocative and X-inefficiencies leading to substantial environmental costs. The motivations of those responsible for the investment decisions are considered within a public choice perspective and a set of incentive-based rules is presented which seeks to help modify their behaviour.