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Court of Appeal Provides Guidance to Water Suppliers Tasked with Preparing Water Supply Assessments

By: Alfred E. Smith, Robert D. Thornton

The California Court of Appeal issued the first published appellate court decision regarding the sufficiency of water supply assessments ("WSA") prepared pursuant to the requirements of SB 610. [1] In O.W.L. Foundation v. City of Rohnert Park, 2008 Cal. App. LEXIS 2268 (November 19, 2008) ("Rohnert Park"), the court upheld the City of Rohnert Park's WSA for a residential and commercial development project in Sonoma County. The decision is important because the court interpreted the landmark state law enacted by SB 610 to provide water suppliers with considerable discretion to adopt technical and practical approaches to evaluating the sufficiency of water supplies for new development.

State law requires public water agencies to prepare a WSA to assess the sufficiency of water supplies for certain proposed development projects, in order to assist local governments in deciding whether or not to approve the projects. (Cal. Water Code, § 10910.) When the water supply for a proposed project includes groundwater, the WSA must discuss and analyze specific information pertaining to groundwater sources and supply. (Cal. Water Code, § 10910(f).)

In Rohnert Park, the petitioners challenged the WSA primarily on the grounds that it did not comply with Cal. Water Code section 10910(f)(5), which requires that a WSA include:

"An analysis of the sufficiency of the groundwater from the basin or basins from which the proposed project will be supplied to meet the projected water demand associated with the proposed project."

The petitioners claimed the WSA did not comply with the Water Code because: (1) the City did not obtain data on groundwater pumping by all users in the groundwater basin; and (2) the City incorrectly defined the applicable groundwater basin. The court evaluated the claims under the traditional mandamus "abuse of discretion" standard and held that the City did not abuse its discretion.

The court concluded that section 10910(f)(5) does not require a "basin-wide study of past and future pumping of all users" but rather requires "consideration of conditions in the relevant groundwater basin in connection with determining whether there is sufficient water to supply the proposed project." (Rohnert Park, supra at *39-41.) The court concluded: "there is nothing in the state statute to suggest that the only way groundwater conditions may be analyzed is by measuring pumping by all users throughout a groundwater basin." (Id. at *41-42.)

The court also stated that SB 610 does not prescribe a particular analytical method, but rather affords "substantial discretion" to a water supplier to select an appropriate method for assessing groundwater sufficiency for a project. (Id. at *47.) The court rejected the contention that basin boundaries set by the Department of Water Resources ("DWR") are required to be utilized in a WSA on the basis that such boundaries may conflict with hydrological realities and might not be appropriate in all circumstances. The court noted that although a water supplier must be afforded discretion to make technical and practical determinations about the appropriate geographical area to support a WSA, such a determination must be supported by evidence that the area studied is appropriate for a particular project and the proposed groundwater supply.

Finally, the Rohnert Park court noted the purpose of the WSA requirement is to "serve the limited function of providing information about groundwater sufficiency for a specific proposed development project" and not to act as a general planning document for the management of groundwater supplies in a basin. (Id. at *45.) The court concluded that it is not appropriate, nor required by the state law, to impose an obligation on water suppliers to engage in a broad inquiry into basin-wide conditions to analyze groundwater sufficiency for a particular project.

Before reaching a decision on the adequacy of the WSA, the court addressed the recent court decision in California Water Impact Network v. Newhall County Water District (2008) 161 Cal.App.4th 1471 ("Water Impact Network"), which held that the adequacy of a WSA is not subject to judicial review independently but rather, may only be contested as part of a challenge to an Environmental Impact Report ("EIR") prepared pursuant to the California Environmental Quality Act ("CEQA") after project approval. The Rohnert Park court agreed with the Water Impact Network decision as a general matter. Nonetheless, the court ruled it had jurisdiction to hear the case even though the petitioner challenged the WSA before adoption of the EIR and before completion of the CEQA review process. The court based its conclusion on the "unique set of circumstances" presented by the case – namely that by the time the adequacy of the WSA was before the court, the EIR had already been certified, and the EIR was being challenged in another lawsuit by the same plaintiff on the same grounds. (Rohnert Park, supra at *23.)

The Rohnert Park court held that the appropriate standard of review for a challenge to the adequacy of a WSA is the abuse of discretion standard applied to traditional mandamus actions. This standard, which allows deference to the agency's authority and presumed expertise, provides that the agency's action must be upheld upon review unless it constitutes an abuse of discretion, and "in general…this inquiry is limited to whether the decision was arbitrary, capricious, or entirely lacking in evidentiary support." (Id. at *30-31.) Rejecting the petitioners' suggestion that the substantial evidence standard applied, the court also noted that, although the City chose to hold a public hearing when adopting the WSA, a hearing was not required; thus, the case was pursued properly as a traditional mandamus action.

This decision is important for water suppliers tasked with preparing WSAs for development projects as it provides guidance on the extent to which groundwater supplies must be analyzed to comply with SB 610, and clarifies the discretion afforded such suppliers in preparing WSAs in connection with the consideration and approval of development projects.

Alfred E. Smith, II specializes in environmental, water and complex commercial litigation. He represents public and private water purveyors, major water users, corporations and public agencies on matters including environmental compliance, water rights disputes, conjunctive use, public utility regulation, groundwater management and litigation over allegedly contaminated water and soil. He can be reached at (213) 612-7800 or

Robert Thornton has practiced environmental law for over twenty-eight years. He represents landowners, resource developers, and public agencies on a variety of environmental matters, including NEPA and CEQA compliance for complex projects. He can be reached at 949.833.7800 or

[1] SB 610 (2001) has been codified at Cal. Water Code section 10910 et seq.

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