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Date: April 18, 2002
Contacts: Jennifer Burris, Media Relations Associate
Andrea Durham, Media Relations Assistant
(202) 334-2138; e-mail <>


National Transportation Air Quality Program
Benefits Local Areas, Warrants Reauthorization

WASHINGTON -- Congress should retain the sole federal surface-transportation program that funds projects to reduce pollution and traffic congestion in areas that must comply with national air quality standards, says a new report from the Transportation Research Board of the National Academies' National Research Council. Strategies tailored by local agencies to address regional pollution and congestion problems are among the program's most important contributions.

"The magnitude of the air quality problem in the United States is large and this program is relatively small," said Martin Wachs, chair of the committee that wrote the report and director, Institute of Transportation Studies, University of California, Berkeley. "But we believe that the projects it funds can help make the difference at the margin in whether an area meets pollution-reduction targets."

The U.S. Department of Transportation's Congestion Mitigation and Air Quality Improvement Program should be modified to reflect changes over the past decade in motor vehicle travel and emissions, the committee added. As vehicles and fuels have become "cleaner," some projects that were effective in the past may be less so in the future. New knowledge about the adverse health effects of pollutants, such as particulates, also calls for different approaches. Other chief recommendations from the committee include keeping air quality improvement a high priority in the program, increasing the role of state and local air quality agencies in reviewing proposed projects, and improving methods for evaluating projects.

Measuring the program's cost-effectiveness at the national level is not possible because the basic data needed to carry out a complete evaluation are not available. However, the potential benefits of the program are sufficiently great to warrant its continuation, the committee said. For example, the program's funds are restricted to projects that reduce pollution, making it the only transportation program with this focus. It enables local areas to experiment with nontraditional strategies for improving air quality and reducing congestion that receive limited funding from other sources. It also encourages new partnerships and interagency arrangements in developing projects.

DOT should make the program more amenable to scientific evaluation by using program funds to encourage more assessments of funded projects, the report says. Even though a national-level assessment of the program's performance is not possible, the agency should evaluate the performance of a sample of projects across regions, broadly disseminate the results, and conduct research on appropriate analysis methods.

Congress enacted the Clean Air Act Amendments in 1990, imposing strict new deadlines for meeting national air quality requirements. To help areas meet the mandates, the Congestion Mitigation and Air Quality Improvement Program was established the following year and reauthorized in 1998 for an additional six years with a total budget of $8.1 billion. During reauthorization, questions were raised about the program's effectiveness in reducing emissions and improving air quality, and Congress ordered an examination of the program by the National Research Council.

The program's funds are distributed to states according to a formula based on the severity of air pollution and the size of affected populations. At the local level, metropolitan planning organizations typically coordinate investment of funds in new facilities and services, with support for operations generally limited to three years. So far, most projects have concentrated on transit and traffic flow improvements, such as freeway incident management systems, traffic signal improvements, and expanded transit services, such as new express bus routes.

Projects that improve air quality should remain the program's major focus, the report says. Consistent with this focus and their charge, state and local air quality agencies should be more directly involved in evaluating proposals for program funding. Any local project that can demonstrate the potential to reduce emissions from transportation sources should be eligible for the program's funding. Congestion-relief projects that can demonstrate pollutant reduction should also be supported, but existing restrictions on new highway construction should be maintained.

To date, the program has focused on regions with ozone and carbon monoxide pollution problems. At a minimum, all pollutants regulated under the Clean Air Act should be covered by the program, both for determining project eligibility and for allocating funds, the report says. These pollutants should include particulates, as well as sulfur dioxide and air toxics.

The study was sponsored by the Federal Highway Administration of the U.S. Department of Transportation. The National Research Council is the principal operating arm of the National Academy of Sciences and the National Academy of Engineering. It is a private, nonprofit institution that provides independent advice on science and technology issues under congressional charter. A committee roster follows.

Copies of The Congestion Mitigation and Air Quality Improvement Program: Assessing 10 Years of Experience are available for free on the Internet at Printed copies are available for purchase from the Transportation Research Board; tel. (202) 334-3213, fax (202) 334-2519, or e-mail <>. Reporters may obtain a copy from the Office of News and Public Information (contacts listed above).

Transportation Research Board
Board on Environmental Studies and Toxicology

Committee for the Evaluation of the Congestion Mitigation and Air Quality Improvement Program

Martin Wachs (chair)
Institute of Transportation Studies, and
Professor of Civil and Environmental Engineering, and
City and Regional Planning
University of California

Carla J. Berroyer
Senior Transportation Policy Specialist
Wilbur Smith Associates
Hot Springs, Ark.

David S. Cordray
Professor of Public Policy, and
Professor of Psychology
Vanderbilt University
Nashville, Tenn.

Henry E. Dittmar
Great American Station Foundation
Las Vegas, N.M.

Eric M. Fujita
Research Professor
Division of Atmospheric Sciences
Desert Research Institute
Reno, Nev.

Genevieve Giuliano
School of Policy, Planning, and Development
University of Southern California
Los Angeles

Joel L. Horowitz
Charles E. and Emma H. Morrison Professor of Economics
Northwestern University
Evanston, Ill.

Alan J. Krupnick
Senior Fellow and Director
Quality of the Environment Division
Resources for the Future
Washington, D.C.

T. Keith Lawton
Director of Technical Services
Planning Department
Portland, Ore.

Michael D. Meyer
Professor of Civil and Environmental Engineering
Georgia Institute of Technology

Michael R. Morris
Director of Transportation
North Central Texas Council of Governments

Robert F. Sawyer
Department of Mechanical Engineering; Energy and Resources Group; and Lawrence Berkeley National Laboratory
Graduate School
University of California

Kenneth A. Small
Professor of Economics
University of California

Katherine F. Turnbull
Associate Director
Texas Transportation Institute, and
Visiting Professor
Department of Landscape Architecture and Urban Planning
Texas A&M University
College Station

Kathleen C. Weathers
Forest Ecologist, and
Head of Laboratory Services
Institute of Ecosystem Studies
Millbrook, N.Y.

Arthur M. Winer
Professor of Environmental Health Sciences
School of Public Health
University of California
Los Angeles


Nancy P. Humphrey
Study Director