Environmental problems in coastal ecosystems can sometimes be attributed to excess nutrients flowing from upstream watersheds into estuarine settings. This nutrient over-enrichment can result in toxic algal blooms, shellfish poisoning, coral reef destruction, and other harmful outcomes. All U.S. coasts show signs of nutrient over-enrichment, and scientists predict worsening problems in the years ahead. Clean Coastal Waters explains technical aspects of nutrient over-enrichment and proposes both immediate local action by coastal managers and a longer-term national strategy incorporating policy design, classification of affected sites, law and regulation, coordination, and communication. Highlighting the Gulf of Mexico's "Dead Zone," the Pfiesteria outbreak in a tributary of Chesapeake Bay, and other cases, the book explains how nutrients work in the environment, why nitrogen is important, how enrichment turns into over-enrichment, and why some environments are especially susceptible. Economic as well as ecological impacts are examined. In addressing abatement strategies, the committee discusses the importance of monitoring sites, developing useful models of over-enrichment, and setting water quality goals. The book also reviews voluntary programs, mandatory controls, tax incentives, and other policy options for reducing the flow of nutrients from agricultural operations and other sources.

New York City's municipal water supply system provides about 1 billion gallons of drinking water a day to over 8.5 million people in New York City and about 1 million people living in nearby Westchester, Putnam, Ulster, and Orange counties. The combined water supply system includes 19 reservoirs and three controlled lakes with a total storage capacity of approximately 580 billion gallons. The city's Watershed Protection Program is intended to maintain and enhance the high quality of these surface water sources. Review of the New York City Watershed Protection Program assesses the efficacy and future of New York City's watershed management activities. The report identifies program areas that may require future change or action, including continued efforts to address turbidity and responding to changes in reservoir water quality as a result of climate change.

The Mississippi River is, in many ways, the nation's best known and most important river system. Mississippi River water quality is of paramount importance for sustaining the many uses of the river including drinking water, recreational and commercial activities, and support for the river's ecosystems and the environmental goods and services they provide. The Clean Water Act, passed by Congress in 1972, is the cornerstone of surface water quality protection in the United States, employing regulatory and nonregulatory measures designed to reduce direct pollutant discharges into waterways. The Clean Water Act has reduced much pollution in the Mississippi River from "point sources" such as industries and water treatment plants, but problems stemming from urban runoff, agriculture, and other "non-point sources" have proven more difficult to address. This book concludes that too little coordination among the 10 states along the river has left the Mississippi River an "orphan" from a water quality monitoring and assessment perspective. Stronger leadership from the U.S. Environmental Protection Agency (EPA) is needed to address these problems. Specifically, the EPA should establish a water quality data-sharing system for the length of the river, and work with the states to establish and achieve water quality standards. The Mississippi River corridor states also should be more proactive and cooperative in their water quality programs. For this effort, the EPA and the Mississippi River states should draw upon the lengthy experience of federal-interstate cooperation in managing water quality in the Chesapeake Bay.

Most water resources managers, scientists, and other experts would agree that nonpoint source pollution is a more pressing and challenging national water quality problem today than point source pollution. Nonpoint sources of pollutants include parking lots, farm fields, forests, or any source not from a discrete conveyance such as a pipe or canal. Of particular concern across the Mississippi River basin (MRB) are high levels of nutrient loadings--nitrogen and phosphorus--from both nonpoint and point sources that ultimately are discharged into the northern Gulf of Mexico (NGOM). Nutrients emanate from both point and nonpoint sources across the river basin, but the large majority of nutrient yields across the MRB are nonpoint in nature and are associated with agricultural activities, especially applications of nitrogen-based fertilizers and runoff from concentrated animal feeding operations. Improving Water Quality in the Mississippi River Basin and Northern Gulf of Mexico offers strategic advice and priorities for addressing MRB and NGOM water quality management and improvements. Although there is considerable uncertainty as to whether national water quality goals can be fully realized without some fundamental changes to the CWA, there is general agreement that significant progress can be made under existing statutory authority and budgetary processes. This book includes four sections identifying priority areas and offering recommendations to EPA and others regarding priority actions for Clean Water Act implementation across the Mississippi River basin. These sections are: USDA's Mississippi River Basin Healthy Watersheds Initiative; Numeric Water Quality Criteria for the northern Gulf of Mexico; A Basinwide Strategy for Nutrient Management and Water Quality; and, Stronger Leadership and Collaboration.