Alleviating Traffic Congestion by the Strategy of Modal Shift from Private Cars to Public Transports: A Case of Dhaka City, Bangladesh

Abstract

Despite much effort, traffic congestion remains a significant concern in urban transportation planning of major cities. Dhaka, the capital of Bangladesh with a population of more than 15 million, is one of such cities that is distressed by severe traffic congestion. The over-reliance on private cars is one of the major causes of city traffic congestion, yet its consequences and alternatives have not been investigated carefully. In this study, a micro-level traffic simulation is designed using the agent-based modeling (ABM) approach representing the traffic flow and the congestion pattern. The characteristics and behaviors of numerous interacting agents, including vehicles, roads, traffic signals, and bus stops, are specified in a spatially explicit road network. Further, the outcomes of modal shift of the daily commuters from private cars to public buses are evaluated. The simulation result shows that, with a modal shift of 20% of private cars’ commuters to public transports, the average traffic speed increases by 10.6% and average travel delay decreases by 12.8%, whereas a modal shift of 40% can raise the speed by 21.0% and reduce the travel delay by 23.2%. Consequently, there is a potential saving of 1.41 and 2.57 million valuable work-hours every year by the 20% and 40% modal shift strategies, respectively, for the studied travel route. This study provides useful information that can support the policymakers to make effective decisions for improving the traffic condition.