15155. WATER SUPPLY ANALYSIS; CITY OR COUNTY CONSULTATION WITH WATER AGENCIES.

• (a) The following definitions are applicable to this section.

  • (1) A “water-demand project” means:

    • (A) A residential development of more than 500 dwelling units.

    • (B) A shopping center or business establishment employing more than 1,000 persons or having more than 500,000 square feet of floor space.

    • (C) A commercial office building employing more than 1,000 persons or having more than 250,000 square feet of floor space.

    • (D) A hotel or motel, or both, having more than 500 rooms.

    • (E) An industrial, manufacturing, or processing plant, or industrial park planned to house more than 1,000 persons, occupying more than 40 acres of land, or having more than 650,000 square feet of floor area.

    • (F) A mixed-use project that includes one or more of the projects specified in subdivisions (a)(1)(A) , (a)(1)(B) , (a)(1)(C) , (a)(1)(D) , (a)(1)(E) , and (a)(1)(G) of this section.

    • (G) A project that would demand an amount of water equivalent to, or greater than, the amount of water required by a 500 dwelling unit project.

    • (H) For public water systems with fewer than 5,000 service connections, a project that meets the following criteria:

      1. A proposed residential, business, commercial, hotel or motel, or industrial development that would account for an increase of 10 percent or more in the number of a public water system’s existing service connections; or

      2. A mixed-use project that would demand an amount of water equivalent to, or greater than, the amount of water required by residential development that would represent an increase of 10 percent or more in the number of the public water system’s existing service connections.

  • (2) “Public water system” means a system for the provision of piped water to the public for human consumption that has 3000 or more service connections. A public water system includes all of the following:

    • (A) Any collection, treatment, storage, and distribution facility under control of the operator of the system which is used primarily in connection with the system.

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  - (B) Any collection or pretreatment storage facility not under the control of the operator that is used primarily in connection with the system. 

  - (C) Any person who treats water on behalf of one or more public water systems for the purpose of rendering it safe for human consumption. 

• (3) “Water acquisition plans” means any plans for acquiring additional water supplies prepared by the public water system or a city or county lead agency pursuant to subdivision (a) of section 10911 of the Water Code.

• (4) “Water assessment” means the water supply assessment that must be prepared by the governing body of a public water system, or the city or county lead agency, pursuant to and in compliance with sections 10910 to 10915 of the Water Code, and that includes, without limitation, the elements of the assessment required to comply with subdivisions (d) , (e) , (f) , and (g) of section 10910 of the Water Code.

  • (5) “City or county lead agency” means a city or county, acting as lead agency, for purposes of certifying or approving an environmental impact report, a negative declaration, or a mitigated negative declaration for a water-demand project.

• (b) Subject to section 15155, subdivision (d) below, at the time a city or county lead agency determines whether an environmental impact report, a negative declaration, or a mitigated negative declaration, or any supplement thereto, is required for the water-demand project, the city or county lead agency shall take the following steps:

  • (1) The city or county lead agency shall identify any water system that either: (A) is a public water system that may supply water to the water-demand project, or (B) that may become such a public water system as a result of supplying water to the water-demand project. The city or county lead agency shall request the governing body of each such public water system to determine whether the projected water demand associated with a water-demand project was included in the most recently adopted urban water management plan adopted pursuant to Part 2.6 (commencing with section 10610) of the Water Code, and to prepare a water assessment approved at a regular or special meeting of that governing body.

  • (2) If the city or county lead agency is not able to identify any public water system that may supply water for the water-demand project, the city or county lead agency shall prepare a water assessment after consulting with any entity serving domestic water supplies whose service area includes the site of the water-demand project, the local agency formation commission, and the governing body of any public water system adjacent to the site of the water-demand project. The governing body of the city or county lead agency must approve the water assessment prepared pursuant to this section at a regular or special meeting.

• (c) The city or county lead agency shall grant any reasonable request for an extension of time that is made by the governing body of a public water system preparing the water assessment, provided that the request for an extension of time is made within 90 days after the date on which the governing body of the public water system received the request to prepare a water assessment. If the governing body of the public water system fails to request and receive an extension of time, or fails to submit the water assessment notwithstanding the 30-day extension, the city or county lead agency may seek a writ of mandamus to compel the governing body of the public water system to comply with the requirements of Part 2.10 of Division 6 (commencing with section 10910) of the Water Code relating to the submission of the water assessment.

to request and receive an extension of time, or fails to submit the water assessment notwithstanding the 30-day extension, the city or county lead agency may seek a writ of mandamus to compel the governing body of the public water system to comply with the requirements of Part 2.10 of Division 6 (commencing with section 10910) of the Water Code relating to the submission of the water assessment.

• (d) If a water-demand project has been the subject of a water assessment, no additional water assessment shall be required for subsequent water-demand projects that were included in such larger water-demand project if all of the following criteria are met:

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• (1) The entity completing the water assessment had concluded that its water supplies are sufficient to meet the projected water demand associated with the larger water-demand project, in addition to the existing and planned future uses, including, but not limited to, agricultural and industrial uses; and

• (2) None of the following changes has occurred since the completion of the water assessment for the larger water-demand project:

  • (A) Changes in the larger water-demand project that result in a substantial increase in water demand for the water-demand project.

  • (B) Changes in the circumstances or conditions substantially affecting the ability of the public water system or the water supplying city or county identified in the water assessment to provide a sufficient supply of water for the water demand project.

  • (C) Significant new information becomes available which was not known and could not have been known at the time when the entity had reached the conclusion in subdivision (d)(1) .

• (e) The city or county lead agency shall include the water assessment, and any water acquisition plan in the EIR, negative declaration, or mitigated negative declaration, or any supplement thereto, prepared for the water-demand project, and may include an evaluation of the water assessment and water acquisition plan information within such environmental document. The city or county lead agency shall determine, based on the entire record, whether projected water supplies will be sufficient to satisfy the demands of the project, in addition to existing and planned future uses. If a city or county lead agency determines that water supplies will not be sufficient, the city or county lead agency shall include that determination in its findings for the water-demand project.

• (f) The degree of certainty regarding the availability of water supplies will vary depending on the stage of project approval. A lead agency should have greater confidence in the availability of water supplies for a specific project than might be required for a conceptual plan (i.e. general plan, specific plan). An analysis of water supply in an environmental document may incorporate by reference information in a water supply assessment, urban water management plan, or other publicly available sources. The analysis shall include the following:

ve greater confidence in the availability of water supplies for a specific project than might be required for a conceptual plan (i.e. general plan, specific plan). An analysis of water supply in an environmental document may incorporate by reference information in a water supply assessment, urban water management plan, or other publicly available sources. The analysis shall include the following:

• (1) Sufficient information regarding the project’s proposed water demand and proposed water supplies to permit the lead agency to evaluate the pros and cons of supplying the amount of water that the project will need.

• (2) An analysis of the reasonably foreseeable environmental impacts of supplying water throughout all phases of the project.

• (3) An analysis of circumstances affecting the likelihood of the water’s availability, as well as the degree of uncertainty involved. Relevant factors may include but are not limited to, drought, salt- water intrusion, regulatory or contractual curtailments, and other reasonably foreseeable demands on the water supply.

• (4) If the lead agency cannot determine that a particular water supply will be available, it shall conduct an analysis of alternative sources, including at least in general terms the environmental consequences of using those alternative sources, or alternatives to the project that could be served with available water.

Note: Authority Cited: Section 21083, Public Resources Code. Reference: Section 21151.9, Public Resources Code, Sections 10910–10915 of the Water Code; Vineyard Area Citizens for Responsible Growth v. City of Rancho Cordova (2007) 40 Cal. 4th 412.

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