Induced Traffic and its Treatment in the Evaluation of Motorway Projects

The purpose of this paper is to define factors that influence the emergence of induced i.e. generated traffic for experts involved in highway feasibility studies. An explanation of the practical methods for forecasting generated traffic is done by reviewing international experiences in the relevant literature. Also, the idea underlying this paper is to explain the different treatments of generated traffic in evaluating highway projects with no tolls, which is based on socio-economic aspects versus the evaluation of highway projects with tolls, which is based on financial aspects. Finally, we propose that since it is hard to measure the economic benefits from indirect effects (in the evaluation of socio-economic aspects) the evaluators could determine the economic benefits of the generated traffic using the same procedure as for normal traffic. KEYWORDS: induced traffic (generated traffic), normal traffic, coefficient of elasticity, time savings, vehicle operating cost (VOC) savings, the economic surplus