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New York City Water Supply

New York City Watershed Program

Where does the NYC water come from?

The NYC watershed is located in Southeastern New York State. Most of the water is provided by precipitation (rain & snow) that falls within the Watershed, flows to nearby streams, then is collected within the reservoirs. All 19 of the reservoirs and their major tributaries within the NYC Watershed Program are monitored continuously. DEC has published reports available on some of the waterbodies. For more detailed information about the NYC Watershed, please visit the Facts about the NYC Watershed page.

Why a New York City Watershed Protection Program?

Map of NYC's water supply system

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The New York City drinking water supply system is the largest unfiltered water supply in the United States (US). It provides approximately 1.2 billion gallons of high quality drinking water to nearly one-half the population of New York State every day. This includes eight million residents of the City and one million consumers located in Ulster, Orange, Putnam, and Westchester counties.

In order to safeguard this irreplaceable natural resource a comprehensive and innovative watershed protection plan was developed and is embodied in the historic and landmark New York City Watershed Agreement (MOA). The MOA was signed in January 1997 and is a partnership agreement.

The partnership was organized to protect and to ensure that New Yorkers continue to enjoy high quality, affordable drinking water and to avoid the need for costly filtration - a cost estimated at between $8.0 to $10.0 billion to construct the facility and approximately $1.0 million each day to operate and maintain the filtration plant.

What is the DEC's Role?

The DEC is an active partner in the management and protection of the New York City Watershed Program (NYCWP). Within the DEC is the Office of the NYCWP. Formed in 1997, it has staff in Central Office and DEC Regions 3 and 4 who work exclusively on the NYCWP. The Program Coordinator, Thomas R. Snow, Jr., who oversees the program, is located in DEC's Central Office in Albany, NY. For more detailed information on the role of DEC, visit the DEC's Role in the NYC Watershed page.

What You Can do!

Each of us lives in a watershed. On our Watershed Stewardship page are some tips on actions that you and your friends can take to help protect and care for your watershed.

Recreational Opportunities in the NYC Watershed

Ashokan Reservoir

Ashokan Reservoir

The NYC Watershed contains some of the greatest recreational and sporting opportunities in New York State. Enjoy the natural environment, delve into history, and enjoy numerous sporting activities, all within a short drive of the New York City. The NYC Department of Environmental Protection (DEP) website lists a number of sites and activities available on NYC Watershed protected lands. Although DEP's primary management goal is watershed protection, a significant portion of City-owned lands is open to the public for a variety of recreational uses and other opportunities (link leaves NYSDEC webpages).

Important On-going Initiatives within the New York City Watershed

  • East of Hudson Municipal Separate Storm Sewer System (MS4) initiative
  • Total Maximum Daily Load (TMDL) Implementation Plan
  • Pharmaceutical Monitoring and collections from health care facilities

Published Water Quality Monitoring and Assessment Reports


More about New York City Water Supply: