There are established techniques for assessing trunk road improvement schemes and other traffic engineering measures. However, there are no comparable methods for evaluating urban traffic management or parking control schemes. This has major implications for the design of an efficient and balanced transport strategy. This paper, a sequel to an earlier one which presented an argument for the development of enhanced evaluation methods (see IRRD 838172) describes the theory behind the design of such methods and outlines how valuation of the broader impacts of various schemes may be achieved. Drawing from the results of a research project recently carried out for the Department of Transport, the paper first addresses the three main theoretical economic issues concerning the design of evaluation methods: valuation of resource costs; benefit valuation; and equity. A framework is also put forward within which the broad spectrum of groups and impacts of relevance to the evaluation are clearly specified. The paper goes on to describe a number of specific methods for valuing the impacts of various traffic management and parking schemes for which there are no existing evaluation techniques. Amongst these are methods for valuing: (a) pedestrian amenity (e.g. from traffic calming or pedestrianisation); (b) changes in travel time variability; (c) parking benefits (willingness to pay for a parking space); and (d) impacts of schemes on goods vehicle operators. Examples are also given of the types of values which may be obtained using the proposed methods and the potential significance of these to the outcome of an appraisal is discussed. Finally, the paper examines the implications of more comprehensive evaluation methods for the introduction of new schemes. The possibilities for developing an evaluation code of practice for practitioners are assessed and suggestions are put forward for the next stage of the research.
Samenvatting