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NOTICE: The project that is the subject of this report was approved by the Governing Board of the National Research Council, whose members are drawn from the councils of the National Academy of Sciences, the National Academy of Engineering, and the Institute of Medicine. The members of the committee responsible for the report were chosen for their special competences and with regard for appropriate balance.
Support for this project was provided by the Comptroller of the City of New York.
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Watershed Management for Potable Water Supply: Assessing the New York City Strategy is available from the
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THE NATIONAL ACADEMIES
National Academy of Sciences
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Institute of Medicine
National Research Council
The National Academy of Sciences is a private, nonprofit, self-perpetuating society of distinguished scholars engaged in scientific and engineering research, dedicated to the furtherance of science and technology and to their use for the general welfare. Upon the authority of the charter granted to it by the Congress in 1863, the Academy has a mandate that requires it to advise the federal government on scientific and technical matters. Dr. Bruce M. Alberts is president of the National Academy of Sciences.
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COMMITTEE TO REVIEW THE NEW YORK CITY WATERSHED MANAGEMENT STRATEGY
CHARLES R. O'MELIA, Chair,
Johns Hopkins University, Baltimore, Maryland
MAX J. PFEFFER, Vice-Chair,
Cornell University, Ithaca, New York
PAUL K. BARTEN,
University of Massachusetts, Amherst
G. EDWARD DICKEY, Consultant,
Baltimore, Maryland
MARGOT W. GARCIA,
Virginia Commonwealth University, Richmond
CHARLES N. HAAS,
Drexel University, Philadelphia, Pennsylvania
RICHARD G. HUNTER,
Florida Department of Health, Tallahassee
R. RICHARD LOWRANCE,
U.S. Department of Agriculture, Tifton, Georgia
CHRISTINE L. MOE,
University of North Carolina, Chapel Hill
CYNTHIA L. PAULSON,
Brown and Caldwell, Denver, Colorado
RUTHERFORD H. PLATT,
University of Massachusetts, Amherst
JERALD L. SCHNOOR,
University of Iowa, Iowa City
THOMAS R. SCHUELER,
Center for Watershed Protection, Ellicott City, Maryland
JAMES M. SYMONS,
University of Houston, Houston, Texas (retired)
ROBERT G. WETZEL,
University of Alabama, Tuscaloosa
Staff
LAURA J. EHLERS, Study Director
ELLEN A. DE GUZMAN, Senior Project Assistant
WATER SCIENCE AND TECHNOLOGY BOARD
HENRY J. VAUX, JR., Chair,
University of California, Oakland
CAROL A. JOHNSTON, Vice-Chair,
University of Minnesota, Duluth
RICHELLE ALLEN-KING,
Washington State University, Pullman
GREGORY B. BAECHER,
University of Maryland, College Park
JOHN S. BOYER,
University of Delaware, Lewes
JOHN BRISCOE,
The World Bank, Washington, D.C.
DENISE FORT,
University of New Mexico, Albuquerque
STEVEN P. GLOSS,
University of Wyoming, Laramie
EVILLE GORHAM,
University of Minnesota, St. Paul
WILLIAM A. JURY,
University of California, Riverside
GARY S. LOGSDON,
Black & Veatch, Cincinnati, Ohio
RICHARD LUTHY,
Carnegie Mellon University, Pittsburgh
JOHN W. MORRIS,
J.W. Morris, Ltd., Arlington, Virginia
PHILIP A. PALMER,
E.I. du Pont de Nemours & Co., Wilmington, Delaware
REBECCA T. PARKIN,
The George Washington University, Washington, D.C.
JOAN B. ROSE,
University of South Florida, St. Petersburg
R. RHODES TRUSSELL,
Montgomery Watson, Pasadena, California
ERIC F. WOOD,
Princeton University, Princeton, New Jersey
Staff
STEPHEN D. PARKER, Director
LAURA J. EHLERS, Senior Staff Officer
CHRIS ELFRING, Senior Staff Officer
JEFFREY W. JACOBS, Senior Staff Officer
WILLIAM LOGAN, Staff Officer
MARK GIBSON, Research Associate
M. JEANNE AQUILINO, Administrative Associate
ANITA A. HALL, Administrative Assistant
ELLEN A. DE GUZMAN, Senior Project Assistant
ANIKE JOHNSON, Project Assistant
COMMISSION ON GEOSCIENCES, ENVIRONMENT, AND RESOURCES
GEORGE M. HORNBERGER, Chair,
University of Virginia, Charlottesville
RICHARD A. CONWAY,
Union Carbide Corporation (retired), South Charleston, West Virginia
THOMAS E. GRAEDEL,
Yale University, New Haven, Connecticut
THOMAS E. GRAFF,
Environmental Defense Fund, Oakland, California
EUGENIA KALNAY,
University of Maryland, College Park
DEBRA KNOPMAN,
Progressive Policy Institute, Washington, D.C.
KAI N. LEE,
Williams College, Williamstown, Massachusetts
RICHARD A. MESERVE,
Covington & Burling, Washington, D.C.
BRAD MOONEY,
J. Brad Mooney Associates, Ltd., Arlington, Virginia
HUGH C. MORRIS,
Canadian Global Change Program, Delta, British Columbia
H. RONALD PULLIAM,
University of Georgia, Athens, Georgia
MILTON RUSSELL,
University of Tennessee, Knoxville
THOMAS C. SCHELLING,
University of Maryland, College Park
ANDREW R. SOLOW,
Woods Hole Oceanographic Institute, Woods Hole, Massachusetts
VICTORIA J. TSCHINKEL,
Landers and Parsons, Tallahassee, Florida
E-AN ZEN,
University of Maryland, College Park
MARY LOU ZOBACK,
United States Geological Survey, Menlo Park, California
Staff
ROBERT M. HAMILTON, Executive Director
GREGORY H. SYMMES, Associate Executive Director
JEANETTE SPOON, Administrative and Financial Officer
SANDI FITZPATRICK, Administrative Associate
MARQUITA SMITH, Administrative Assistant/Technology Analyst
Preface
Watersheds are nature's boundaries for surface water supplies. Natural processes combined with human activities in watersheds determine the inherent quality of these supplies and the treatment they need for potable use. The quality of the drinking water at a consumer's tap depends on the source of that water and, in turn, on the approaches used in managing the activities and processes in the watershed from which the water originates. The effectiveness of these approaches depends to a significant extent on their scientific underpinnings. This report examines watershed management for the water supply of the City of New York. In doing so, it can serve as a prototype for other urban surface water supplies.
In 1997 the National Research Council (NRC), under the auspices of the Water Science and Technology Board (WSTB), established the Committee to Review the New York City Watershed Management Strategy. The NRC chose 15 experts to serve on the committee for the purpose of studying scientific issues associated with the 1997 New York City Watershed Memorandum of Agreement (MOA), a document that outlines strategies for maintaining high-quality drinking water for the nine million residents in New York City and neighboring Westchester County. The MOA has allowed New York City to obtain a filtration waiver under EPA's Surface Water Treatment Rule for its Catskill/Delaware supply system until April 2002. In exchange, the City must (among other things) comply with water quality standards for contaminants in drinking water, it must maintain a watershed protection program (embodied in the MOA), and it must not experience a waterborne disease outbreak.
The MOA is a monumental document in the history of water resources in New York City. There are three main provisions of the agreement: (1) land
purchase in the Catskill/Delaware watershed, which supplies 90 percent of the city's drinking water and is predominantly in private ownership, (2) regulations on activities in the watershed, and (3) payments to watershed communities to support local economic development and to promote watershed protection. The MOA owes its existence to multiple parties in New York City, New York State, and the watershed communities, each of which made concessions to protect water quality in the Catskill/Delaware supply and also to meet the needs of the watershed citizens.
To carry out this study, committee members were chosen from a broad range of backgrounds including hydrology, watershed management, environmental engineering, ecology, microbiology, public health and epidemiology, urban planning, economics, and environmental law. The committee met six times over the course of two years, commencing in New York City on September 25, 1997. The third committee meeting was held in the watershed region (Oliverea, NY) to allow the members to visit several of the upstate reservoirs, observe New York City Department of Environmental Protection (NYC DEP) operations, visit a farm enrolled in the Watershed Agricultural Program, and learn about ongoing basic science research in the watershed. At all of the committee's open meetings, the public took great interest in committee deliberations and guest presentations. In all, the committee heard from over 40 invited speakers. In addition, liaisons were established with multiple stakeholders who supplied considerable written information during the course of the study.
Beyond regular committee meetings, four additional activities were undertaken to broaden the knowledge base of the committee. First, a small field trip to the Kensico Reservoir was made in November 1997. In April 1998, six prominent scientists convened with a subgroup of the committee to discuss active disease surveillance in New York City and the prospects for conducting a microbial risk assessment for the Catskill/Delaware supply. In the summer of 1998, committee members met with citizens and farmers in Delaware County and toured the headquarters of the Catskill Watershed Corporation. Finally, in January 1999 the expertise of six buffer zone scientists was used to supplement the committee in its assessment of the adequacy of setbacks in the watershed. The following individuals are thanked for their participation and contribution to these efforts. The members of the Panel on Microbial Risk Assessment are Gunther Craun, Craun and Associates; James Miller, New York City Department of Health; Mark Sobsey, University of North Carolina; William MacKenzie, Centers for Disease Control; and Joan Rose, University of South Florida. The buffer zone experts are David Correll, Smithsonian Environmental Research Center; Art Gold, Rhode Island Department of Natural Resources; Peter Groffman, Institute of Ecosystem Studies; Nick Haycock, Quest Environmental; James Hornbeck, USDA Forest Service; and Lyn Townsend, University of Washington.
In conducting this study, the committee encountered numerous issues that inspired controversy and debate, two of which are noted here. First, out of
consideration for time and overall effectiveness, the Croton water supply is not a primary focus of this report. Given the large number of tasks it was addressing, the committee concluded that it could not provide a comprehensive evaluation of Croton watershed issues, many of which differentiate it considerably from the Catskill/Delaware watershed. In particular, New York City is currently under order to filter the Croton system. Kensico and West Branch reservoirs, which are physically located in the Croton watershed, are included in the report to the fullest extent possible. Second, because the filtration avoidance determination for New York City includes the dual-track approach of conducting watershed management and designing a water filtration plant, the report discusses filtration and its benefits. However, in the committee's opinion, this report, which focuses on watershed management, was not the appropriate place to evaluate the global issue of whether all surface waters need treatment beyond disinfection.
Although watershed management is important for any surface water supply, it is critical for an unfiltered supply. The MOA is a remarkable document and a significant milestone in the City's water supply and the region's development. Successful implementation of the MOA is the most important challenge facing the City's water supply managers. It is also important to stress that watershed management is an iteractive, living process. This report and its recommendations are provided to support the implementation of the MOA and to contribute to the maturation of the watershed management program.
This report has been reviewed, in accordance with NRC procedures, by individuals chosen for their expertise and their broad perspectives on the issues addressed herein. This independent review provided candid and critical comments that assisted the authors and the NRC in making the published report as sound as possible, and it ensured that the report meets institutional standards for objectivity, evidence, and responsiveness to the study charge. The content of the review comments and the draft manuscript remain confidential to protect the integrity of the deliberative process. The committee thanks the following individuals for their participation in the review of this report and for their many instructive comments: Derek Booth, University of Washington; Kenneth Brooks, University of Minnesota; Gunther Craun, Craun and Associates; Joseph Delfino, University of Florida; Theo Dillaha, Virginia Polytechnic Institute and State University; Walter Lynn, Cornell University; Patricia Miller, Virginia Department of Natural Resources; Jerry Ongerth, University of New South Wales; Joan Rose, University of South Florida; Milton Russell, University of Tennessee; Rhodes Trussell, Montgomery Watson; and Robert Tucker, Rutgers University. These individuals have provided many constructive comments and suggestions. Responsibility for the final content of this report, however, rests solely with the authoring committee and the NRC.
Special thanks must go to several individuals who contributed to the committee's overall effort in so many ways. First, the committee thanks Nancy Anderson and Steve Newman of the New York City Office of the Comptroller.
The committee benefited from their insight into the problems and needs of the City with respect to watershed management. Second, considerable thanks must go to our liaisons at the New York City Department of Environmental Protection: Bill Stasiuk, David Warne, Mike Principe, Salome Freud, Kimberly Kane, David Stern, Ira Stern, Jim Miller, Arthur Ashendorff, and Jim Benson. Third, I appreciate the extensive input from the environmental community in New York City, particularly Eric Goldstein, Robin Marx, and Mark Izeman of the Natural Resources Defense Council and David Gordon of the Hudson Riverkeeper. Finally, I thank our upstate contacts: Alan Rosa of the Catskill Watershed Corporation and Gail Sheridan and Dick Coombe of the Watershed Agricultural Council. All these individuals spent considerable time and energy compiling and passing to the committee the information it needed to complete this study.
Finally, I would like to thank vice chair Max Pfeffer, the members of this committee, study director Laura Ehlers, and project assistant Ellen de Guzman, all of whom devoted many long hours to this project. I have enjoyed immensely the opportunity to work with such a talented and articulate group of professionals. They provided a stimulating environment for addressing the study issues. I especially appreciate their willingness to spend time researching, writing, and revising their contributions. I believe the results of their efforts provide useful guidance for watershed management in the New York City watersheds. This guidance should also be relevant to a broader universe of watershed management programs.
Charles R. O'melia, chair