N.Y. Public Health Law § 1125
1. Definitions. As used in this title:
2. All water suppliers shall prepare a water supply emergency plan; provided, however, if more than one water supplier is responsible for the same system, such plan shall be submitted jointly by such two or more water suppliers. The plan shall identify and outline the steps necessary to ensure that potable water is available during a water supply emergency. The water supply emergency plan shall include, but not be limited to, the following: