An economic appraisal of the impact of traffic diversion : the N1 toll road and its alternative

Abstract

This paper investigates two alternative roads running parallel to one another; one being a double-carriageway national road that was tolled 4 years ago and the other being an inter-city single-carriageway road. The purpose of the paper is to test the application of the World Bank-developed Road Economic Decision (RED) model for assessing the economic impact of traffic diversion between two existing alternative roads. In order to do so, the RED model is first used to conduct a cost–benefit analysis of each road in isolation. Thereafter, the model is used to do a scenario analysis followed by a sensitivity analysis. The results show that the RED model is a useful tool for evaluating the impact on society of diverted traffic between alternative roads elsewhere in South Africa.