The purchase, announced in late December, is the single most expensive land acquisition DEP has ever made for watershed protection. Over nearly 200 years, New York City has acquired or protected more than 200,000 acres of land across its upstate watershed, primarily in the Catskill Mountains, where most of the city’s drinking water originates. All of that water ultimately passes through the Kensico Reservoir on its way to homes and businesses across the region.

DEP already owns land along the entire shoreline of the Kensico Reservoir and several nearby parcels. Adding this forested 48-acre property increases protection of natural streams and hillsides that help filter stormwater before it reaches the reservoir. The purchase aligns with a recent recommendation from the National Academies of Sciences, Engineering and Medicine to prioritize investments in land parcels that offer the greatest water-quality benefits.

Since the late 1980s, federal rules have required municipal surface-water supplies to be filtered and disinfected. New York City and select other municipal water supplies have been able to achieve a waiver to filtration—known as a Filtration Avoidance Determination (FAD)—when extraordinary efforts are undertaken to protect the water supply at its source. New York City’s most recent 10-year waiver is up for renewal at the end of 2027. Building a filtration plant for the entire supply from the Catskills would surpass the largest capital investment the city has ever undertaken.

Mount Pleasant Supervisor Carl Fulgenzi said, “This acquisition, 48 acres of the former Legionaries property, is especially meaningful to us and puts this property back on the tax rolls after many years. Our community also receives water directly from the Kensico outlet works, and the preserved land will also create valuable new green space for our residents. We deeply appreciate both the land protection efforts and the ongoing infrastructure investments that NYC DEP continues to make in our community. These actions reflect their dedication to safeguarding the watershed and ensuring the delivery of the highest‑quality drinking water.”

DEP is closely monitoring potential risks to water quality, including climate-driven extreme weather, droughts, and changing regulations. These efforts help ensure that the city remains ahead of emerging challenges, particularly in Westchester and Putnam counties, where development pressures and evolving water quality concerns require proactive and adaptive management.

The Kensico Reservoir, located just north of White Plains, has supplied water to New York City since 1915. It can hold up to 30 billion gallons of water and typically handles about 90 percent of the city’s total drinking water supply, as well as water for much of Westchester County.