Traffic Management:

Federal Policies to Encourage Low-Cost Approaches Need to Be Strengthened

PEMD-91-26BR: Published: Aug 28, 1991. Publicly Released: Oct 7, 1991.

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Pursuant to a congressional request, GAO evaluated federal efforts to encourage better management of the nation's highways through the use of low-cost transportation systems management (TSM) techniques, focusing on: (1) federal-aid funding incentives; (2) transportation planning requirements; and (3) technical assistance for innovative TSM practices.

GAO found that: (1) TSM encompasses low-cost techniques for improving the efficiency of surface transportation, including supply management techniques, which include traffic signal coordination and ramp metering, and transportation demand management techniques, which include carpooling and vanpooling; (2) federal efforts to achieve widespread TSM usage have not been fully successful; (3) over the last decade, the actual total expenditures for TSM with federal aid has remained small relative to total allocations; (4) although the federal government has sought to promote better supply and demand management by including certain TSM projects under an incentive provision that included other operational improvements, the provision has not significantly influenced the amount of TSM implemented; (5) transportation planning requirements alone appear to be insufficient to guarantee that TSM and transportation demand management are implemented, due to local reluctance to fully embrace transportation demand management and an uncertain connection between transportation planning and any consequent project funding; (6) federal policy could further support innovative strategies to better manage traffic demand through ongoing technical assistance; and (7) due to 1990 Clean Air Act requirements, the need for technical assistance could increase greatly.

Matter for Congressional Consideration

  1. Status: Closed - Implemented

    Comments: The recently passed highway reauthorization legislation includes the three recommended actions.

    Matter: When reauthorizing the Surface Transportation Act and other related legislation, Congress should consider enhancing the federal role in encouraging traffic management techniques, including: (1) creating an incentive system that targets federal-aid highway funds specifically for transportation system management activities; (2) developing a planning process that highlights and gives funding priorities to low-cost approaches to congestion mitigation; and (3) establishing and funding a technical assistance program on innovative transportation demand management strategies.


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