Knowledge Resources

This report summarized the results of several ITS evaluation projects in the city of San Antonio, Texas. San Antonio had a relatively extensive implementation of ITS prior to this study and, consequently, the incremental benefits experienced in San Antonio through expansion and additions to the existing system may be somewhat smaller than the benefits that could be achieved in areas with little prior implementation of ITS.

The evaluation report detailed benefits information regarding the implementation of an incident management program with dynamic message signs (DMS) along a freeway corridor and traffic signal timing control operations along a parallel arterial. Through a modeling effort, the study investigated the impacts of each implementation individually, and also evaluated the combined impact of integrating the DMS with incident management and then integrating both the DMS and incident management with traffic signal timing plan alterations along an alternative arterial route.

Results indicate that the most effective stand-alone implementation is incident management, recording improvements in all impact measures assessed. DMS and arterial traffic signal control can provide additional improvement under many of these areas. For the particular corridor modeled during this study, optimum implementation of the integrated DMS and incident management result in a 2.8 percent decrease in crashes. Integrated use of incident management, DMS and arterial traffic control can achieve a 2.0 percent decrease in crashes.