California Partners for Advanced Transportation Technology

This paper presents and discusses how traffic information is obtained and how it affects travel behavior when a major freeway is congested. Immediately following a major highway incident south of San Francisco which caused congestion, a telephone survey was conducted of commuters who utilize the affected corridor of highway. The behavior of commuters before and during their commute at the time of the incident was determined, including obtaining traffic information and how the information influenced changes in route, mode of travel and departure time. The results of the survey suggest that commuter travel behavior is largely unaffected by individual incidents of congestion. Furthermore, although a fair proportion of commuters do obtain traffic information, they do not often modify their travel behavior in response. This study is one of several which collectively will provide insight into how travel behavior changes over time and allow us to assess the impact of the TravInfo traveler advisory telephone system (TATS) in the San Francisco Bay Area. Keywords: travel behavior traffic information