Market Research Evaluation of Actions to Reduce Suburban Traffic Congestion: Commuter Travel Behavior and Response to Demand Reduction Actions

Frank S. Koppelman, Chandra R. Bhat and Joseph L. Schofer
Northwestern University, Evanston, Illinois 60208

This research paper is directed toward obtaining a better understanding of current work trip mode choice of commuters in suburban areas and the effectiveness of alternate demand reduction actions in alleviating congestion based on a Chicago area study. Demand reduction actions are "behavior-change" oriented and attempt to alleviate congestion by encouraging individuals to change their commute pattern. This paper is particularly concerned with an evaluation of the effectiveness of demand reduction actions that encourage the use of ridesharing modes (car-pool, van-pool and transit) and/or discourage the use of drive-alone auto for the work trip. A conceptual framework of current mode-choice behavior and behavioral response to demand reduction actions is developed. The empirical analysis suggests that in the Midwest suburban setting, any substantial increase in ride sharing propensity appears to require a combination of ride sharing incentives in the form of improved service characteristics and direct auto-use disincentives in the form of substantially increased parking costs. Our analysis also suggests that ride sharing propensity is greater for women and individuals in households with fewer autos. Individuals who have a great need for independence, make additional trips on their way to and from work, frequently stay late at work, and have a high income tend to be less inclined to use ridesharing modes.