Regions and municipalities across the United States are considering various forms of congestion pricing as a way to optimize transportation system efficiency. The Southern California Association of Governments (SCAG) has undertaken a multiyear effort to study eight different congestion pricing strategies with the goals of reducing congestion, reducing vehicle emissions, and enhancing revenue potential.
Understanding the behavioral response of travelers to different forms of pricing is important when evaluating the policy implications of individual pricing projects or combinations of congestion pricing strategies. RSG designed a comprehensive survey tool to evaluate the behavioral response of travelers to eight different congestion pricing strategies, including various forms of individual facility pricing, regional facility pricing, HOT lanes, area or cordon pricing, parking pricing, and VMT pricing. The survey instrument simultaneously evaluated potential shifts to mode, route, and time of day, as well as trip suppression under the eight pricing strategies.
The internet-based survey was administered to a total of 3,590 residents across the entire six-county SCAG region. The survey data were used to develop multinomial logit models for four traveler market segments. The models provided information about the sensitivities of travelers in the region to travel time, toll cost, and shifts to mode, route, and time of day. The resulting sensitivities to travel time and toll cost, along with the information obtained in the survey about changes in trip frequency, were used to develop regression models to forecast trip suppression. The final results of the discrete choice and trip suppression models will support updates to the regional travel demand model to evaluate various congestion pricing projects and policies.