N.Y. Gen. Mun. Law § 76
Notwithstanding the provisions of any general or special law, a municipal or other corporation not situated within the county of Westchester or the county of Putnam shall not have power to acquire by condemnation, for the purpose of increasing or improving the water supply of any such corporation, or for supplying the inhabitants thereof with water, any lands, easements, streams of water, or water rights within the county of Westchester or the towns of Carmel and Putnam Valley in the county of Putnam, except that this section shall not apply to the contemplated reservoir known as the Cross river reservoir, nor to the contemplated reservoir at or near Croton falls, nor to the contemplated acquisition of land in the vicinity of Rye lake; nor shall this section operate to prevent the city of New York from acquiring real estate in said counties necessary for the purpose of constructing, maintaining and operating aqueducts, dams, reservoirs, culverts, sluices, canals, bridges, tunnels, pumping works, blow-offs, shafts, filters and appurtenances for the purpose of conveying to the city of New York and to the said counties, water from sources outside of the said counties, or for the purpose of connecting supplies of water already established within said counties, nor shall this section operate to prevent the city of New York from acquiring such real estate within the Croton watershed in the county of Westchester, contiguous to Little Mohansic Lake and Mohansic Lake, as may be necessary for the sanitary protection of the water supply of the city of New York, and the city of New York is hereby authorized to acquire by purchase or by condemnation in the manner prescribed by the provisions of title two, chapter eleven of the Greater New York charter as amended, such real estate for such purposes, except the lands, buildings and premises known as the Mohansic Lake reservation in the town of Yorktown, the county of Westchester, transferred and conveyed by the people of the state of New York to the county of Westchester by chapter two hundred and seventy-six of the laws of nineteen hundred and twenty-two.
N.Y. Gen. Mun. Law § 76