Assessment of crash location improvements in map-based geocoding systems and subsequent benefits to geospatial crash analysis

According to the 2009 South Carolina Traffic Collision Factbook, a fatality occurs in South Carolina every 9.8 hours and an injury every 10.9 minutes. These rates rank among the highest in the country. Furthermore, South Carolina incurs over two billion dollars in economic loss annually due to road traffic crashes. The South Carolina Department of Transportation (SCDOT), in collaboration with the South Carolina Department of Public Safety (SCDPS), has undertaken a series of initiatives in an effort to reduce the number of vehicle crashes, especially injury and fatal crashes that occur every year in South Carolina. One of these initiatives is the deployment of a map-based crash geocoding system that has greatly improved the quality of the location data. This paper examines the progression in crash location data quality in South Carolina by reviewing improvements made to crash data collection methods over recent years and analyzing subsequent benefits of having higher quality crash data from a spatial analysis perspective. Geographic Information System (GIS) analytical tools are used to help assess improvements in geocoding accuracy. A case study evaluation of driveway related crashes, occurring in close proximity to intersections, is presented as one of the many benefits of having more spatially accurate crash data.