METHODOLOGY FOR RANKING ROADSIDE HAZARD CORRECTION PROGRAMS

This paper describes the development and use of a computerized system to facilitate the prioritizing of roadside fixed-object treatments. Developed for the Traffic Engineering Branch of the North Carolina Division of Highways, the system is designed to perform economic analyses of various fixed-object improvements on an areawide, or roadway segment, basis for example, determining the effect of removing all trees with 9 m (30 ft) of the edge of pavement on rural, two-lane, secondary roads in the piedmont area of North Carolina. Developed inputs for the system include: (a) frequency and severity of the most affectable accidents for each given hazard-treatment. System outputs include predicted accident savings, the net discounted present value and benefit-cost ratio for each candidate fixed-object treatment, and a priority ranking based on comparisons of net present value. Initial runs using the system indicated that the use of transition guardrail at hazardous bridge ends and tree removal in certain locations in North Carolina appear promising. System developmental efforts also remphasized the continuing presence of a serious national problem-the lack of sound information concerning effectiveness levels for fixed-object countermeasures. /Author/