Performance and design of intersections

The operation and safety characteristics of the road system depend more on intersections than any other single parameter under the control of the road or traffic engineer. It is at intersections that the majority of vehicle and pedestrian conflicts occur and therefore where delays, accidents and congestion are likely to occur. The importance of intersections in respect to road safety is emphasised by accident statistics which show that about 60 per cent of all casualty accidents in urban areas in Victoria occur at intersections. In rural areas some 25 per cent of all casualty accidents occur at intersections. This section deals with a number of aspects of the design of intersections (including roundabouts), including: choice of intersection type; performance of intersections; objectives of intersection design; intersection design and control; elements of design and standards; and special forms of intersection treatment (A).