N.Y.C. Admin. Code § 24-327: § 24-327 Regulation of use of Putnam county lakes and reservoirs used for city water supply.

Whenever the waters of natural lakes in Putnam county have been or are acquired by the city, or reservoirs have been or are constructed, the residents of such county shall have the right of boating, fishing and taking ice from such lakes and reservoirs, subject to such regulations as the commissioner of environmental protection may make from time to time to preserve the purity of the water and to prevent nuisances, and subject, however, to the right of the city to prohibit such use in the event of the declaration of an emergency as provided in section 24-326 of this code.