THE SIGNIFICANCE OF ENVIRONMENTAL CAPACITY IN THE ASSESSMENT OF THE TRAFFIC IMPACTS OF DEVELOPMENTS

In assessing the traffic impacts of land-use developments, impacts on traffic efficiency and the capacity of the road network are well understood, as are impacts on the road pavement, where heavy vehicles are involved. However, the potential impacts on amenity and safety are not as clearly understood. To assess these issues, the environmental capacity of the roads in question should be part of the review. This paper develops performancestandards for environmental capacity. These standards are based on considerations of pedestrian safety and delay, traffic noise, the attitude of residents to traffic flows and a consideration of the planning objectives in design guidelines for new residential subdivisions. The major part of this paper reviews past research and current guidelines on these factors, while data obtained in previous research on resident perceptions of trafficis further analysed. The essence of the paper is the distillation of this information into pragmatic guidelines for practical application. (a) For the covering abstract of this conference see IRRD abstract no. 861222.