The cost-effectiveness of high-occupancy-vehicle (HOV) lanes was analysed by comparing the costs and benefits of existing HOV lanes with the hypothetical alternatives of doing nothing or adding a lane for general traffic. Three specific sites in the seattle area were studied. A life-cycle costing approach was used. The main result of the study was that for the three locations studied, the construction of HOV lanes was the most cost-effective alternative. The marginal net present value of each of the projects was positive (on the order of $50 to $600 per commuter per year, depending on the specific comparison). The marginal benefit/cost ratio was greater than 6 for all cases. Using extreme values for the elements of the model had little impact on the outcome of the study. Using extreme values for any one factor did not come close to reversing any of the findings; it required extreme values for virtually all of the factors for reversal.It is extremely unlikely that all the elements of the model were distorted in a direction to cause this outcome. The methodology developed for this study was incorporated into an easy-to-use personal computer program that assesses the cost-effectiveness of the construction of HOV lanes in other locations. In order to save the costs of extensive data collection, the sensitivity analysis approach developed in this study proved to be a valuable tool in the analysis of sites for HOV lanes.
Abstract