Pursuant to a congressional request, GAO reviewed the Department of Transportation's (DOT) efforts to reduce traffic congestion, focusing on: (1) DOT assistance to communities in alleviating traffic congestion; (2) resources DOT used to support its congestion reduction activities; and (3) DOT evaluations of the effectiveness of its congestion reduction activities.

GAO found that: (1) the main DOT congestion reduction effort involved providing federal assistance to state and local governments for road construction and reconstruction, transportation systems management, and advanced technology; (2) the Federal Highway Administration (FHwA) administered five major highway construction and maintenance programs, at a cost of $3.9 billion during fiscal year (FY) 1988; (3) although FHwA monitored the performance of major U.S. roadways and occasionally assessed program management, it did not evaluate program effectiveness; (4) while FHwA encouraged the use of federal-aid highway funds for transportation systems management, the Urban Mass Transportation Administration (UMTA) supported the use of transit formula and discretionary funds for those purposes; (5) although FHwA and UMTA spent at least $188 million in FY 1988 funds on transportation systems management projects, neither FHwA nor UMTA had transportation system management evaluation activities that were comparable to efforts they had conducted 10 years earlier; (6) federal research activities in advanced technology cost at least $3.5 million in FY 1988, with FHwA assigning a high priority to examining the use of such technologies as advanced freeway traffic control systems and advanced motorist information systems; (7) FHwA and UMTA administered several congressionally requested studies; and (8) FHwA worked with other federal and local groups to develop a more aggressive program for researching and developing advanced technologies.