This paper presents a discussion on how traffic information is obtained and how the congestion of a major freeway affects travel behavior. It reports on survey results of commuters affected by two highway incidents south of San Francisco. The survey collected information on travel behavior, how the traffic information was obtained, and how it influenced route, model of travel and departure time. Results of the surveys suggest that travel behavior is largely unaffected by individual incidents of congestion. The study is also one of several designed to provide an assessment of the impact of the TravInfo traveler advisory telephone system (TATS) in the San Francisco Bay Area.

This report contains detailed work plans for the following evaluation tasks associated with the TravInfo evaluation study. These include: the target, Value Added Reseller (VAR) customer studies, and the network performance evaluation. The target study focuses on a high impact Bay Area corridor to evaluate TravInfo impacts or benefits to Bay Area travelers. The network performance evaluation simulates the road conditions in that corridor to estimate TravInfo impacts at the aggregate level. The VAR customer study provides information on those consumers who actually purchase and use Advanced Traveler Information Systems (ATIS) devices and subscribe to TravInfo