Highway Congestion:

Intelligent Transportation Systems' Promise for Managing Congestion Falls Short, and DOT Could Better Facilitate Their Strategic Use

GAO-05-943: Published: Sep 14, 2005. Publicly Released: Sep 14, 2005.

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Phillip R. Herr


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Congestion is a serious and growing transportation problem for the nation. Many strategies--like adding new lanes--have the potential to alleviate congestion but can be costly and have limited application. Another strategy is the use of communications, electronics, and computer technologies--intelligent transportation systems (ITS)--to more effectively utilize existing transportation infrastructure by improving traffic flow. Congress established an ITS program in 1991, and the Department of Transportation (DOT) subsequently set an ITS deployment goal. In this report GAO (1) describes the federal role in deployment; (2) assesses DOT's ITS goal and measurement efforts; (3) identifies what ITS studies have found regarding the impacts of ITS deployment; and (4) identifies the barriers to ITS deployment and use.

The federal role in ITS deployment includes goal setting, funding, and facilitating states' investment in ITS. In 1991, Congress set broad goals and established funding for ITS, and in 1998, Congress established a program to support ITS deployment. In a 1996 speech, the Secretary of Transportation established a vision for ITS deployment to save time and lives and improve quality of life. As part of this vision, the Secretary also established a goal that the 75 largest metropolitan areas deploy a complete ITS infrastructure by 2005 and measures to track progress toward this goal. DOT has taken several actions to support this goal, though it does not plan to update it. Progress has been made toward achieving DOT's deployment goal, but DOT's goal and measures have limitations and fall short of capturing ITS's impact on congestion. Among other things, the measures do not capture the extent to which deployed ITS technologies are effectively operated, and we found that some metropolitan areas' operations of ITS technologies are limited. For example, Chicago developed 10 traffic management centers to monitor and respond to traffic congestion by notifying emergency responders of traffic accidents, among other things; however, 6 centers do not have full-time operators, which is likely to limit their impact on congestion mitigation. Many of the ITS studies we reviewed suggest that ITS deployment can have benefits such as relieving congestion, traffic throughput, safety, and air quality. Results from some studies suggest that ITS benefits depend on effectively operating ITS technologies to meet local conditions. However, few studies provided information about cost effectiveness of the ITS deployments, which is essential for maximizing public investments. According to transportation officials GAO spoke with, barriers to ITS deployment and use include the limited public awareness of the impact of ITS, difficulty of funding ITS operations, limited technical expertise, and lack of technical standards. DOT actions have had limited success in overcoming these barriers.

Recommendations for Executive Action

  1. Status: Closed - Not Implemented

    Comments: The Department of Transportation (DOT) did not revise its deployment survey to take into account local needs or the operating status of intelligent transportation system (ITS) technologies because DOT moved away from a deployment-focused program under the Safe, Accountable, Flexible, Efficient Transportation Equity Act: A Legacy for Users (SAFETEA-LU) and let lapse the Secretary of Transportation's 1996 goal of achieving a complete ITS infrastructure in 75 metropolitan areas. In 2005, under SAFETEA-LU, DOT shifted its focus from directly supporting ITS deployment projects to supporting research initiatives and deployment support activities, such as coordinating standards development and professional capacity building. In addition, DOT no longer measures metropolitan areas in terms of how complete or fully integrated their ITS deployments are, although the Federal Highway Administration continues to survey metropolitan areas every two years regarding deployment of ITS technologies.

    Recommendation: The Secretary of Transportation should revise measures for ITS deployment to incorporate local needs and operational status for deployed ITS technologies.

    Agency Affected: Department of Transportation

  2. Status: Closed - Implemented

    Comments: According to DOT officials, the Joint Program Office is continuing efforts to make state and local government agencies fully aware of the eligibility of ITS operational improvements for Federal funding. Specifically, DOT officials plan to brief various stakeholder groups on the specific provisions of SAFETEA-LU dealing with operations, congestion, and ITS and plan to make sure that this issue is clearly addressed in briefing materials. DOT is also working with various organizations such as ITS America and the American Association of State Highway and Transportation Officials (AASHTO) to ensure this issue is clearly addressed. DOT officials added that this is a continuing effort.

    Recommendation: The Secretary of Transportation should develop new strategies to better advertise the availability of federal funds for operating ITS technologies.

    Agency Affected: Department of Transportation

  3. Status: Closed - Implemented

    Comments: The Department of Transportation (DOT) acknowledged that cost effectiveness is one of a number of criterion that states and localities should consider when making transportation system improvement decisions, including intelligent transportation system (ITS) deployments, and has taken steps to highlight cost effectiveness analyses. For example, DOT has compiled ITS deployment studies that include cost to benefit calculations in its benefits database. In addition, the ITS Joint Program Office (ITS JPO) promote ITS-related evaluation tools, such as the ITS Deployment Analysis System (IDAS), in its 2007 ITS resource guide. IDAS is a software program for state and local planners to evaluate the costs and benefits associated with ITS investments. Finally, according to a JPO official we contacted, ITS JPO contributed to a rulemaking by the Federal Highway Administration and Federal Transit Administration on statewide and metropolitan area transportation planning to produce a final rule that requires state transportation improvement plans to (1) more explicitly consider ITS and ITS data in developing congestion management processes and (2) include financial information containing system-level estimates of costs and revenue sources.

    Recommendation: The Secretary of Transportation should encourage cost-effectiveness analyses and their use in transportation planning and decision making.

    Agency Affected: Department of Transportation


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