HSC §18941.8: (a) As used in this section, “graywater” has the same meaning as defined in Section 17922.

(a) As used in this section, “graywater” has the same meaning as defined in Section 17922.12. (b) Notwithstanding Chapter 22 (commencing with Section 14875) of Division 7 of the Water Code, as a part of the next triennial edition of the California Building Standards Code (Title 24 of the California Code of Regulations) adopted after January 1, 2011, the commission shall adopt building standards for the construction, installation, and alteration of graywater systems for indoor and outdoor uses in nonresidential occupancies. (c) In adopting building standards under this section, the commission shall do all of the following: (1) Ensure protection of water quality in accordance with applicable provisions of state and federal water quality law. (2) Consider the adopted building standards for the construction, installation, and alteration of graywater systems for indoor and outdoor uses in residential buildings. (3) Consider existing research available on the environmental consequences to soil and groundwater of short-term and long-term graywater use for irrigation purposes. (4) Consider graywater use impacts on human health. (5) Consider the circumstances under which the use of graywater treatment systems in nonresidential occupancies is recommended. (6) Consider the use and regulation of graywater in other jurisdictions. (7) Use Chapter 16 of the Uniform Plumbing Code, adopted by the International Association of Plumbing and Mechanical Officials, as the starting point for the building standards and amend those standards as necessary. (d) The commission may revise and update the standards adopted under this section at any time. (e) The commission’s adoption of building standards for graywater systems pursuant to this section shall terminate the authority of the Department of Water Resources to adopt and update standards for the installation, construction, and alteration of graywater systems in nonresidential buildings pursuant to Chapter 22 (commencing with Section 14875) of Division 7 of the Water Code.