Pricing road space: back to the future? The Cambridge experience

Cambridge is a small free standing city in the UK with a population of 105 000. In recent years it has endured a worsening congestion problem essentially as a result of employment growth within the city and the narrow street layout. This is not a unique problem but one which is particularly acute in historic cities. In 1990, Congestion Metering was advanced, in addition to a number of other measures, as a means of managing traffic demand within the city. It has generated a great deal of interest internationally, particularly the field trial which took place in October 1993. This was the first time that any form of road pricing had been demonstrated practically in the UK. The aim of this article is to provide a review, establishing why the idea of Congestion Metering was originally considered and why, at least in the short to medium term, it is unlikely to be implemented in a Cambridge context. The process by which, if adopted, it is envisaged that Congestion Metering would be introduced is outlined, and the relative merits and potential weaknesses of such a demand management measure. Finally, the author considers the real problem of 'public scepticism' which needs to be addressed if Congestion Metering is to avoid the pitfalls which have bedevilled other road pricing schemes world-wide.