Crash Rates At Intersections

The objectives of this study were to develop a database of intersections, match traffic crashes to these intersections, calculate crash rates for various types of intersections, and identify intersections with the highest crash rates. A procedure was used to: a) identify intersections, b) assign crashes to these intersections, c) determine entering traffic volume, d) calculate a crash rate for each intersection, and e) calculate a critical rate factor (CRF) for each intersection. About 7,000 intersections were identified with almost 19,000 crashes related to these intersections for the three-year period of 2000 through 2002. The analysis identified 428 intersections that had a CRF of one or more while only 36 intersections had a CRF above two. As would be expected, the crash rates are higher in urban than in rural areas. In both rural and urban areas, the rate was highest for four-lane undivided highways and lowest for four-lane divided highways. An Excel spreadsheet containing a list of all intersections of two or more state-maintained roadways was developed. The spreadsheet also contains crash and volume data for each intersection. The intersections with the highest critical rate factors can be identified. This list can be divided by highway district with the objective of investigating the intersections with the highest CRFs and determining if improvements should be implemented