Chapter 7. Traffic Forecasting and the Appraisal of Road Schemes

Volume 1 Part 2
Brief résumé of Chapter 7:
Traffic Forecasting and the Appraisal of Road Schemes

Professor H. J. Wootton CBE, BSc(Eng), MEng, C.Eng, FICE, FIHT, FCIT
Rees Jeffreys Professor of Transport Planning, University of Southampton
formerly Director, Transport and Road Research Laboratory
Past President IHT

In this essay, from a career in consultancy, as Chief Executive of the Transport Research Laboratory, as Visiting Professor in computing at King's College London and as the Rees Jeffreys Professor of Transport Planning at Southampton University, Professor Wootton traces four decades of development of methodologies of estimation and appraisal which have been devised to illuminate the implications of designing particular extensions to Britain's motorway system, and of implementing those designs or refraining from doing so. The tale is one of progressive elaboration of economic and environmental factors brought to account in quantified form and of environmental factors in unquantifiable form.

Professor Wootton's account goes on to show both where limits have been encountered upon the feasibility of designing such methodology in a form applicable on a common national basis and how, despite the improved capacity to perceive the implications of a project, a degree of disinclination has persisted in recent years even to consider in public how far local, regional or national interest would be affected either by adopting or by rejecting a particular motorway project.

He raises the question whether such disinclination will survive change to be expected in future, partly because of continuing increase in access to vehicles, themselves safer, cleaner and more comfortable, and partly because of technological developments in external means of regulating their use or performance, in the manner in which motorways having matured in their environments will be used and their potential value realised at that time.