Chapter 6. Motorway Traffic in Great Britain

Volume 1 Part 2
Brief résumé of Chapter 6:
Motor Traffic in Great Britain

Professor T. E. H. Williams CBE, PhD, FICE, FCIT, FIHT
formerly Chairman, SACTRA
Past President, IHE

Professor Williams' second essay opens with statistical facts about the surge in growth of traffic on Britain's roads from 1953 onwards. The figures show the rising and widening ownership of cars, their increasing use and the growing length of journeys. Those involved in planning, designing, constructing and operating provision for traffic had to secure regular information about these trends locally, and from that information to construct mathematical models of the future to be planned for. To operate an effective programme of marshalling so much data and making so many calculations required computers; and in good time they arrived. This development made it practicable to compare several alternative projects in the same time frame and to accommodate public participation in the process of choice by Ministers. Ministers stood in the same need to be convinced by the information, particularly because adoption of a motorway project would itself change the conditions of traffic and of the environment.

Professor Williams refers to work in the USA on traffic analysis in the 1950s and by the Road Research Laboratory in Britain over the next two decades. Review in the late 1970s by the Advisory Committee on Trunk Road Assessment focused upon the debatable, and long debated, questions how far a motorway, providing the benefits of reduced journey times and greater safety, will change the routes of existing traffic and how far, if at all, it will generate new traffic. or contribute to new development which in turn will generate new traffic.

Measurement of the scale and characteristics (for example, the freight fleet component) of traffic flows over time became correspondingly important for policy and planning. Professor Williams' study summarises the figures which emerged and traces their influences upon the national economy and upon regional regeneration, expressed in changes in employment and in location of industrial and commercial investment. By reference to the Tyne Tunnel and its projected duplication by a scheme within the Government's Private Finance Initiative, he emphasises that the economic justification for a motorway may derive from developments going far beyond the compass of the motorway project itself.