Water Code § 1009
CHAPTER 1. Definitions and Interpretation of Division
Any supplier of water in this state for municipal use, including the state, or any city, county, city and county, district, individual, partnership, corporation, or any other entity, may undertake a water conservation program to reduce water use and may require, as a condition of new service, that reasonable water-saving devices and water reclamation devices be installed to reduce water use.