EFFECT OF INTERSECTIONS ON DRIVEWAY ACCIDENTS

Detailed tabulation has been made of over 15,000 accidents in two Illinois suburbs -- one adjacent to the City of Chicago and the other at the outer fringe of the continuously developed area. Breakouts were available of accidents by type of occurrence (pedestrian/bike, parked car, fixed object, driveway and other vehicle-vehicle collisions). Additional breakouts include intersection versus midblock conditions and by functional classification of streets (major, collector, and local). Driveway accidents related to intersections were found to represent only 1.2% of total accidents (6.3% of driveway accidents) in one city and in the second 2.0% of total accidents (6.9% of driveway accidents). Neither of the cities placed any limitation on driveway proximity to intersections, other than clearing the corner radius. These findings suggest access management policies restricting driveways closer to intersections than distances such as Florida's 230 ft, have not been supported based upon safety. Similarly, policies on driveway spacing such as Michigan's 300 to 500 ft and Florida's 125 to 660 ft (if based on claims of traffic hazard) may be considered suspect. Recommendations are listed relative to appropriate techniques for conducting studies of driveway accidents, including use of hard copies rather than printouts, access to location-type files, identification of police agencies producing high-quality reports, avoidance of systems containing only accident data limited to some property damage cutoff, and careful tabulation of appropriate data.