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.
Improvements to elements of San Antonio’s traveler information system included the installation of In-Vehicle Navigation (IVN) devices in vehicles operated by public agencies in the San Antonio area. The IVN devices provided navigational assistance, incorporating information on congestion, incidents and railroad crossing status when planning trips.
The small number of publicly owned vehicles using the IVN devices led to no system impact from these devices, however, modeling results indicated significant potential benefits for individuals using the devices. Over a one-year period a traveler using an IVN device could experience an 8.1 percent reduction in delay, a 4.6 percent reduction in the crash rate, and a 3 percent reduction in fuel consumption.