ANALYSIS OF TRAFFIC ACCIDENT LOCATION AND HAZARD PERCEPTION USING GIS

This paper describes how traffic accident death tolls in Japan have been reduced from the peak of 17 thousand in 1970 to less than 10 thousand in 1996 and remains at about the 9 thousand level for the past several years. However, the number of traffic accidents and injuries are steadily increasing and number of people injured exceeded one million for the first time in 1999 despite of various countermeasures to deal with the accident reduction. Conventional countermeasures are mostly hardware-oriented, such as installation of traffic signals, delineation of lane marks and median strips, separation of pedestrian sidewalk by guardrails, and so on. However, it seems that the conventional countermeasures to provide safety equipment and infrastructure is not effective enough to reduce traffic accidents. Therefore, it is necessary to introduce a new approach to cope with the increasing traffic accidents. One aspect is to examine the road user's attitude or perception about the hazardous location especially in their neighborhood. Recently elderly casualties are rapidly increasing exceeding those of younger generations due to the aging population structure in Japan. The activity space of elderly people is mostly near their residences, and it is a growing concern that the accidents involving elderly population in the neighborhood is on the rise. Until now, various traffic safety measures are not necessarily directed to specific group of population such as senior citizens or housewives. In this study a detailed survey was conducted to collect location data of both accidents occurred and people's perception of dangerous spots and their mutual relationships by various socio-demographic groups. In order to reduce traffic accidents, it is very important to know what kind of accidents occurred where and why. Until recently little work has been done in Japan to build traffic accident databases that use Geographic Information Systems (GIS) to record the accurate location of accident due to the lack of coordination between police and highway department. Therefore, it has been difficult to identify locations where traffic accidents occur frequently. However, efforts to coordinate the traffic accident data from police and the road data from highway department started mainly by the Institute for Traffic Accident Research and Data Analysis (ITARDA), and they successfully identified 3200 locations nationwide where traffic accidents occurred frequently. Currently various measures are being taken to improve these accident-prone intersections and road sections. However, these 3200 locations are on national highways and major regional arterial highways only, and local streets are excluded from the tally. The accident statistics show nearly half of traffic accidents occur on the municipal streets in the residential area. In this study we tried to examine all accidents in a study area regardless of the road jurisdiction.