Measuring and Assessing Traffic Congestion: A Case Study

Aerial photograph of road


Measuring and assessing traffic congestion can be a difficult task in practice. This paper presents a case study investigating a highly congested signalized intersection in Melbourne. This is the intersection of Alexandra Parade and Wellington Street which has long queues on the westbound approach of the intersection extending upstream onto the Eastern Freeway section during AM peak period. Real-life traffic data obtained from VicRoads including SCATS data for the intersection, freeway speed and flow data from freeway detectors on the upstream section, and data from special saturation flow and lane blockage surveys conducted at the intersection were used in a detailed paired intersection model developed using SIDRA INTERSECTION 6.0 software. The paper demonstrates various difficulties encountered in the analysis of congestion in practice. The importance of using demand flow data under congested conditions and the impact of queue spillback in reducing saturation flow rates and intersection capacities is emphasised.


YUMLU, C., MORIDPOUR, S. and AKÇELIK, R. (2014). Measuring and Assessing Traffic Congestion: A Case Study. Paper presented at the AITPM 2014 National Conference, Adelaide, Australia, Aug 2014.