Date: June 15, 2001
Contacts: Bill Kearney, Media Relations Officer
Mark Chesnek, Media Relations Assistant
(202) 334-2138; e-mail <>

Water Quality Management Needs Improvement;
Better Data Analysis and Two-Step Process Could Aid States

WASHINGTON -- A more science-based approach is needed to improve a federally mandated program that requires states to clean up the nation's lakes, rivers, and other bodies of water, says a new report from the National Academies' National Research Council. Despite three decades of progress in controlling discharges from waste-water treatment plants and industry, pollution from other sources is jeopardizing water quality and the ability of states to achieve further progress.

Under the 1972 Clean Water Act, each state must identify polluted waters, put them on its so-called 303d list, and establish what are known as Total Maximum Daily Loads (TMDLs), which determine the amount by which sources of pollution would need to be reduced to meet the state's standards. During previous decades, states focused on issuing permits to control industrial and municipal discharges into bodies of water from point sources, such as an identifiable pipe or channel. Now the focus has shifted to implementing the TMDL process and controlling pollutants, such as nutrients, bacteria, and sediments, that frequently come from various nonpoint sources, including urban storm water and agricultural runoff. And there is increased attention on other factors affecting water quality such as habitat alteration.

"State agencies need to use better data and tools to establish appropriate water quality standards, determine whether standards have been violated, and develop restoration plans," said Kenneth H. Reckhow, chair of the committee that wrote the report, and professor, Duke University, Durham, N.C. "The state of the science is sufficient to overhaul the current lists of impaired waters and aid states in determining more workable solutions for cleaning them up."

About 21,000 bodies of water have been placed on 303d cleanup lists. Because of time and resource constraints coupled with legal pressures, many water bodies were put on state lists without adequate water quality data, creating a large caseload requiring cleanup efforts, said the committee. Considerable uncertainty exists about whether some of these waters violate standards. In addition, other waters that are impaired have yet to be identified.

The report calls on EPA to implement a two-step process that puts certain waters on a preliminary list before moving them to the final 303d list of those that require cleanup. This approach would give states time to study those bodies of water for which scant data exist while concentrating efforts on sites found to be in greatest need. If no legal mechanism exists for states to move waters from the 303d list to a preliminary list, Congress should create one, the committee said. However, no body of water should remain on a preliminary list for more than a predetermined period that allows for problems to be identified and solutions developed.

To improve the TMDL process, states should develop more refined water quality standards including the use of biological measurements to complement physical and chemical ones. The report promotes greater use of statistical approaches for the design of monitoring programs and for the analysis of data to determine if standards have been violated. Scientific uncertainty -- caused, for example, by limited data or natural variability -- should be acknowledged and taken into account. So that TMDL plans are not halted because of a lack of scientific information, the states should adopt an approach called adaptive implementation, whereby plans are periodically assessed and revised using new data and scientific tools.

Since the TMDL program is a significant financial burden for states, Congress might consider aiding states through matching grants to carry out water quality studies, the committee added.

The TMDL process has become one of the most discussed and debated environmental programs in the nation, as drafting and revising of the final rules for implementation and enforcement has taken place in the last year. Last October, Congress suspended EPA's implementation of these rules until further information could be gathered. In particular, Congress asked the National Research Council to examine the program's scientific basis for determining which waters are impaired and for developing TMDLs. Under 1992 regulations, states are required to meet a deadline of 8 to 13 years for establishing the TMDLs. Only six states have enough data to fully assess the condition of their waters, according to the General Accounting Office.

The committee's work was funded by the Environmental Protection Agency. The National Research Council is a private, nonprofit institution that provides science policy advice under a congressional charter granted to the National Academy of Sciences. A committee roster follows.

Copies of Assessing the TMDL Approach to Water Quality Management are available from the National Academies Press on the Internet at or by calling 202-334-3313 or 1-800-624-6242. Reporters may obtain a pre-publication copy from the Office of News and Public Information (contacts listed above). .

Division on Earth and Life Studies
Water Science and Technology Board

Committee to Assess the Scientific Basis of the Total Maximum Daily Load Approach
to Water Pollution Reduction

Kenneth H. Reckhow (chair)
Professor of Water Resources
Nicholas School of the Environment
Duke University, and
Water Resources Research Institute
University of North Carolina

Anthony S. Donigian Jr.
President and Principal Engineer
Aqua Terra Consultants
Mountain View, Calif.

James R. Karr
Professor of Aquatic Sciences and Zoology, and
Adjunct Professor of Environmental Engineering, Environmental Health, and Public Affairs
University of Washington

Jan Mandrup-Poulsen
Environmental Administrator
Watershed Assessment Section
Florida Department of Environmental Protection

H. Stephen McDonald
Carollo Engineers
Walnut Creek, Calif.

Vladimir Novotny
Professor of Environmental and Water Resources Engineering, and
Institute for Urban Environmental Risk Management
Marquette University; and
AquaNova International Ltd.

Richard A. Smith
Research Hydrologist
Water Resources Division
U.S. Geological Survey
Reston, Va.

Chris O. Yoder
Ecological Assessment Section
Ohio Environmental Protection Agency


Laura J. Ehlers
Study Director