Facilitating Demand with Technology
Another approach to providing for growing demand is to use computer and communications technologies to increase the efficiency of the existing network (). Since 1991, Congress has provided roughly $100 million annually in research and development (R&D) funding to consolidate the efficiency gains offered by such technologies under the rubric of intelligent transportation systems (ITS).
ITS h
as spawned a variety of new services and operational capabilities, such as real-time traveler information, regional traffic operations services, and improved emergency response. Such technologies hold considerable promise. At the same time, however, they raise questions about how a national program can be integrated with existing institutional responsibilities and how public agencies and vehicle and component manufacturers can collaborate to allow vehicle and infrastructure systems to operate together effectively. Resolving these questions is an ongoing challenge for the U.S. Department of Transportation (USDOT) since it encourages greater orientation toward operating systems supported by ITS technologies among the thousands of state and local agencies responsible for building, maintaining, and operating transportation infrastructure.
Perhaps the most ambitious ITS concept advanced in ISTEA was the proposed development of automated highways. Automated highways were envisioned as increasing throughput dramatically while simultaneously reducing crashes. In ISTEA, Congress challenged USDOT to create, test, and select a prototype automated highway system within 7 years. To this end, a public–private consortium was formed to develop and test automation concepts. Those concepts were demonstrated in San Diego, California, in 1997.
Although the demonstration showcased some exciting technologies, the committee that reviewed the national automated highway research program found that daunting technical, social, and institutional issues would haveto be addressed before such a system could become a reality in any metropolitan area. For example, although the demonstrated technologies would enable remarkably high throughput on high-volume urban Interstates feeding into the heart of a congested urban area, they could not resolve the complex problem of allocating these increased traffic volumes safely and efficiently into the traffic streams of already congested local streets. Even so, the committee urged USDOT to continue to explore the potential for using automation in specific circumstances, as well as the possibilities for developing vehicle-based safety-enhancing technologies for cars, trucks, and transit vehicles (discussed later in the section on managing risk) (Special Report 253; National Automated Highway System Research Program: A Review; TRB 1998).