Knowledge Resources

The U.S. Department of Transportation study "What Have We Learned About ITS?" is a synthesis of the national experience with implementing ITS through the year 2000, with a goal of more effectively planning the future of the National ITS Program. This synthesis examines which ITS technologies and applications have been successful, which have not, and those for which more information is needed to make a judgment. The seven areas included within the scope of this study are as follows:

• Freeway, Incident, and Emergency Management, and Electronic Toll Collection (ETC)

• Arterial Management

• Traveler Information Systems

• Advanced Public Transportation Systems

• Commercial Vehicle Operations (CVO)

• Cross-Cutting Technical Issues

• Cross-Cutting Institutional Issues

Advanced Traveler Information Systems that provide both static and dynamic information on arterial roadway conditions offer benefits in customer satisfaction and improved efficiency. In surveys conducted on traveler information systems in Seattle, Phoenix, and San Antonio; respondents suggested adding arterial information. The Seattle study demonstrated that adding arterial data to a traveler information system can reduce delay by 3.4 percent—compared to a 1.5 percent delay reduction without arterial data—and lead to significant reductions in travel time variability.