Date: April 4, 2000
Contacts: Molly Galvin, Media Relations Officer
Mark Chesnek, Media Relations Assistant
(202) 334-2138; e-mail <>

National Strategy Needed to Protect Coastal Areas
From Dangerous Levels of Nitrogen and Phosphorus

WASHINGTON -- The federal government -- together with state and local agencies -- should develop a comprehensive national strategy to combat nitrogen and phosphorus pollution in coastal waters, says a new report by the National Research Council of the National Academies. The overabundance of these nutrients -- especially nitrogen -- is causing serious environmental damage on all of the nation's coasts, said the committee that wrote the report. Nitrogen makes its way to coastal waters from the atmosphere and upstream watersheds, via rivers that have been polluted by agricultural runoff, waste-water treatment plants, and the burning of fossil fuels.

"Excess nitrogen in our coastal waters starts a dangerous chain of ecological events that is exacerbating harmful algal blooms such as red tides, contaminating shellfish, killing coastal wildlife, reducing biodiversity, destroying sea grass, and contributing to a host of other environmental problems," said committee chair Robert Howarth, professor of ecology and environmental biology at Cornell University, Ithaca, N.Y. "Conditions in many coastal areas are expected to worsen unless action is taken now to reduce nutrient pollution. The federal government should work with state and local agencies to develop a coordinated national plan that will curb nutrient excesses in U.S. waters."

Coastal environmental quality could be significantly improved if local and state agencies focused on identifying sources of excess nutrients and reducing their release, the committee said. However, local and state oversight often is not sufficient for protecting large watersheds that span several states or for dealing with pollution sources that are far from coastal areas. Nutrients can be carried for long distances in rivers or in the atmosphere. Better coordination also is needed among the many state, regional, and federal programs already in place.

Of 139 coastal areas assessed recently, 44 were identified as severely affected by high levels of nitrogen and phosphorus, the report says. Problems are particularly severe along the mid-Atlantic coast and the Gulf of Mexico, where a "dead zone" forms along the Louisiana and Texas coasts each spring. Nitrogen and phosphorus are naturally occurring nutrients that are critical to support plant life in marine ecosystems. But too much of either nutrient – especially nitrogen -- causes an overabundance of phytoplankton and other organisms, which in turn use up available oxygen and destroy or drive away other marine life. These algal blooms and the excess nutrients that cause them have been linked to the decline of some fisheries, manatee deaths on the Florida coast, and the loss of coral reefs and other important marine habitats.

Human activities have more than doubled the amount of nitrogen in the environment globally from 1960 to 1990, the report says, with the use of synthetic fertilizers accounting for more than half of that growth. In the United States, approximately 20 percent of the nitrogen in these fertilizers seeps into ground water, rivers, and streams, gradually making its way into coastal waters. Other sources of nitrogen include animal wastes, waste-water treatment plants, and the combustion of fossil fuels. These fuels release nitrogen compounds into the atmosphere that fall in acid rain, adding significant amounts of nitrogen to some coastal waters.

At a minimum, the committee said, a national strategy should strive to reduce the number of severely damaged coastal areas by at least 25 percent before 2020 and ensure that no other healthy coastal areas become affected.

The committee identified several initiatives to enhance the efforts of coastal and watershed managers in addressing nutrient overabundance, including the following:

Expand monitoring and assessment programs. Accurate estimates of nutrients in waterways that lead to the coast are essential for developing effective strategies to combat excesses. Federal, state, and local agencies should form partnerships with academic and research institutions to develop a monitoring program for the nation's coastal areas. A national assessment should be conducted every 10 years to determine the extent of nutrient problems and the effectiveness of efforts to combat them. In addition, the U.S. Department of Agriculture and the Environmental Protection Agency (EPA) should monitor the success of various approaches to reduce excess nitrogen from agricultural practices and fossil-fuel combustion.

Exert federal leadership on issues that span multiple jurisdictions or threaten federally protected natural resources. The government should continue to set clear guidelines for the maximum amounts of nutrients, or loads, that are released in waterways. EPA should continue to develop standards for different types of regional watersheds, focusing their efforts on identifying the sources of nutrients and setting maximum daily loads. The government also should use incentives for farmers and industries to control or reduce nutrient releases. For example, subsidies could be used to encourage landowners to implement agricultural practices that would limit the release of nitrogen in waterways.

Address overlaps and gaps in existing and proposed federal legislation. Because several federal agencies and regulations already address nutrient pollution in waterways, the government should ensure that programs are focused on effectively meeting the needs of local authorities. In addition, excess nutrients should be an important consideration in the reauthorization of the Clean Water Act, the Clean Air Act, and the Coastal Zone Management Act, all of which will affect the management of nutrient levels in coastal areas.

Provide data, information, and technical assistance to state and local coastal authorities. Such efforts could include a federally managed clearinghouse that provides assistance on request, or a complete database on the Internet with links to information. Research should be expanded to improve the understanding of the causes, and environmental and economic impacts, of nutrient contamination.

Develop a classification scheme to provide better information on the likelihood that excess nutrients will damage coastal areas. Many factors influence how excess nutrients will affect coastal waters, such as the depth of the water and whether nutrients are flushed out to sea by tides or currents. Better data on these factors would foster information exchanges among coastal managers and scientists, and allow authorities to identify more effective strategies for protecting coastal zones.

The study was funded by the National Oceanic and Atmospheric Administration, the Environmental Protection Agency, the U.S. Geological Survey, and the Electric Power Research Institute. The National Research Council is the principal operating agency of the National Academy of Sciences and the National Academy of Engineering. It is a private, nonprofit institution that provides science advice under a congressional charter. A committee roster follows.

Read the full text of Clean Coastal Waters: Understanding and Reducing the Effects of Nutrient Pollution for free on the Web, as well as more than 1,800 other publications from the National Academies. Printed copies are available for purchase from the National Academy Press Web site or at the mailing address in the letterhead; tel. (202) 334-3313 or 1-800-624-6242. Reporters may obtain a pre-publication copy from the Office of News and Public Information at the letterhead address (contacts listed above).

Commission on Geosciences, Environment, and Resources
Ocean Studies Board
Water Science and Technology Board

Committee on the Causes and Management of Coastal Eutrophication

Robert W. Howarth (chair)
Professor of Ecology
Program in Biogeochemistry and Environmental Change
Cornell University
Ithaca, N.Y.

Donald M. Anderson
Senior Scientist
Department of Biology
Woods Hole Oceanographic Institution, and
Director of the National Office for Marine Biotoxins and Harmful Algal Blooms
Woods Hole, Mass.

Thomas M. Church
College of Marine Studies
University of Delaware

Holly Greening
Senior Scientist
Tampa Bay National Estuary Program
St. Petersburg, Fla.

Charles S. Hopkinson Jr.
Senior Scientist
The Ecosystems Center
Marine Biological Laboratory
Woods Hole, Mass.

Wayne C. Huber
Professor of Civil, Construction, and Environmental Engineering
Water Resources Engineering Department
Oregon State University

Nancy H. Marcus
Department of Oceanography
Florida State University

Robert J. Naiman
College of Ocean and Fishery Sciences
University of Washington

Kathleen Segerson
Professor of Economics
Department of Economics
University of Connecticut

Andrew N. Sharpley
Soil Scientist
Pasture Systems and Watershed Management Research Laboratory
U.S. Department of Agriculture
University Park, Pa.

William J. Wiseman Jr.
Director of the Coastal Studies Institute, and
Professor of Oceanography and Coastal Sciences
Louisiana State University
Baton Rouge


Dan Walker
Study Director