The cost-effectiveness of roadside improvements was compared with road improvements on two-lane rural highways in illinois. Accident reductions due to the improvements on 17 resurfacing, restoration, and rehabilitation projects were determined, and the benefits from the accident reductions were compared with the improvement costs. Accident data for 2 years before and 2 years after the improvements were extracted for two categories: (a) fixed-object, off-roadway, single-vehicle (FOS) accidents and (b) related accidents, which include overturned, other noncollision, head-on, and sides wipe accidents in addition to the FOS accidents. The roadside improvement costs were used in a benefit/cost analysis of the FOS accidents, and the road improvement costs were used in a benefit/cost analysis of the related accidents. Benefits, in terms of number of accidents reduced, were computed using the before-and-after study with control site approach. Roadside improvements reduced accidents by 7.02 per year, road improvements by 33.35 accidents per year. On the average, for every $28,471 spent on the roadside improvement, or for every $26,487 spent on the road improvement projects, one accident was reduced. The benefit/cost ratios for roadside improvements were very similar to those for road improvements. The cost-effectiveness approach and benefit/cost analysis indicated that the roadside improvements provided similar benefits to the road improvements. A more comprehensive study with a larger number of sites is suggested to evaluate the cost-effectiveness of highway improvements over a longer period of time.
Abstract