Study of traffic crashes in Chittagong city

Abstract

Road traffic crashes are causing great concern to the community. It is found that road fatalities are increasing steadily and the safety problem is very severe by international standards, but local initiatives to improve the situation are very sparse. A detailed study of traffic crashes in Chittagong metropolitan area for two and a half years (January 1993 to June 1995) has been made. The purpose of the study was to investigate and analyse the accident factors and high accident locations, and to recommend some possible low cost engineering treatments to minimise crashes and their resulting casualities. There were 522 police reported crashes, which were distributed as 271 (52%) at intersections and 246 (48%) on mid blocks (links). From the analysis, 12 intersections and 10 mid-blocks were identified as hazardous locations with high number of crashes in the metropolis. About 53 percent of total intersection accidents occured at only 20 percent of total intersections with three or more accidents and about 58 percent of total midblock accidents occured at only 26 percent midblocks with three or more accidents. Trucks are the most predominant type of vehicles in each police station and one- third of total vehicles involved in accidents are trucks in the entire metropolitan area. Accident type analysis was carried out by using the "Definition for Classifying Accident" (DCA) codes. Pedestrian accidents and rear -end collisions were the most frequent types of accidents, 43 percent and 22 percent respectively. About 76 percent of total accidents were attributed to three dominant accident types viz. pedestrian accidents, rear-end collisions and headon collisions. Approximately one third of total accidents occurred on the two main arterial sections: from Bahaddar Hat to Custom (30% in 12 km road length) and New market to Kadamtali (3% in 2 km road length). These sections are charactarised as divided carriageways with signalization at intersections and heavy traffic flow. Accidents peaked in the periods 9 A. M. to 11 A. M. (approximately 15%) in the morning and 2 P. M. to 3 P. M. (approximately 7.5%) in the afternoon. After detailed analysis of crash characteristics, remedial treatments for intersections and mid-blocks were suggested for safety improvements. Elements of safety measures included such as Pedestrian crossing facilities (zebra crossings, pedestrian refuges, raised platform of pedestrian crossing), Speed reduction devices (road humps, rumble strips), Segregation of slow and fast moving vehicles (lane markings), Median barrier etc. These measures have considerable proven safety benefits and are important for urban areas in Bangladesh particularly in the Chittagong metropolitan area.