Travel, Emissions, and Welfare Effects of Travel Demand Management Measures
Land-use intensification measures and pricing policies are compared and combined with high-occupancy vehicle (HOV) lane and light-rail transit expansion scenarios in the Sacramento, California, region and evaluated against travel, emissions, consumer welfare, and equity criteria. A state-of-the-practice regional travel demand model is used to simulate the travel effects of these scenarios. The Small and Rosen method of obtaining consumer welfare is applied to the mode-choice models in the travel model. The most politically feasible scenarios were found to provide at best only modest improvements in congestion and emissions. Welfare losses were obtained for the HOV lane scenario, suggesting that care must be taken in project planning to ensure that savings in travel time are large enough to offset the unobserved cost of increased travel by car. Transit investment and supportive land-use intensification provided larger reductions in congestion and emissions and increased consumer welfare for all income classes. As a group, the scenarios that included pricing policies provided the greatest reduction in travel delay and emissions, increased total consumer welfare, and imposed losses on the lowest income group. However, it may be possible to combine pricing policies with more significantly expanded transit and roadway capacity and compensatory payments to increase consumer welfare for all income classes.