Water Supply Sufficiency Analyses Must Consider Groundwater Sustainability

Gov. Jerry Brown has signed Senate Bill 1262 into law, representing an initial attempt to incorporate groundwater management requirements under the Sustainable Groundwater Management Act into two of California’s water supply planning laws. SB 1262 amends Water Code section 10910 of the Water Supply Assessment statute (commonly referred to as “SB 610”) and Government Code section 66473.7 of the Written Verification statute (commonly referred to as “SB 221”). While SB 1262 begins to address the relationship between California’s water supply planning laws, many questions remain unanswered.

Both Water Supply Assessments and Written Verifications apply to certain types of development projects. Each requires a specific analysis of whether sufficient water supplies will be available to serve a proposed project in addition to existing and planned future uses. Among other things, SB 1262 amends the WSA and WV statutes to require those water supply analyses to consider the most recently adopted Groundwater Sustainability Plan prepared under SGMA if the water supply for a proposed project includes groundwater from a basin designated as medium- or high-priority.

SGMA was adopted in 2014 and, for the first time in California, establishes statewide requirements for establishing sustainable groundwater management in all basins designated by the California Department of Water Resources as medium- or high-priority. Under SGMA, Groundwater Sustainability Agencies must be established by June 30, 2017 and GSPs must be adopted by 2020 or 2022, depending on whether a basin is deemed to be critically overdrafted, to achieve groundwater sustainability within 20 years from adoption. Notably, prior to SB 1262, neither SGMA nor California’s water supply planning statutes made any reference to how GSPs may relate to WSAs or WVs. SB 1262 changes that, although the change is very slight and many other issues still must be addressed.

Amendments to the WSA statute (Wat. Code § 10910)

As mentioned above, SB 1262 amends Water Code section 10910 to require certain SGMA-related information to be included in a WSA being prepared for a project under the California Environmental Quality Act. Specifically, if a water supply for a proposed project includes groundwater from a basin that is not adjudicated and is designated as medium- or high-priority, the following additional information must be included in the WSA: whether DWR has identified the basin as being subject to critical conditions of overdraft; and if a GSA has adopted a GSP or approved an alternative plan under SGMA, a copy of the GSP or alternative plan. For a basin that is not adjudicated and is designated by DWR as low- or very low-priority, the WSA must include information as to whether DWR has identified the basin as being overdrafted or projected that the basin will become overdrafted if present management conditions continue. SB 1262 also amends Water Code section 10910 by stating that “hauled water” is not considered a source of water for purposes of preparing a WSA.

Amendments to the WV statute (Gov. Code § 66473.7)

SB 1262 amends Government Code section 66473.7 in similar ways. Now under the WV statute, where a proposed “subdivision” (a residential development of more than 500 units) relies in whole or in part on groundwater, the following information must be considered in a WV:

1. for an adjudicated basin, the order or decree adopted by the court or the State Water Resources Control Board;
2. for a basin that is not adjudicated and is designated as medium- or high-priority under SGMA, the most recently adopted GSP or approved alternative plan; and
3. for medium- or high-priority basins where no GSP or alternative has been approved, and for basins designated as low- or very low-priority under SGMA, information as to whether DWR has identified the basin as being overdrafted or projected that the basin will become overdrafted if present management conditions continue.

The undefined relationship between SGMA and California’s water supply planning laws

SB 1262 represents an initial effort to address the relationship between SGMA and two of California’s other water supply planning laws, i.e., the WSA and WV statutes. In sum, SB 1262 requires WSAs and WVs to consider the most recently adopted GSP(s) or alternative plan(s) prepared under SGMA when a proposed project relies in whole or in part on groundwater. Viewed another way, for projects that rely on groundwater, SB 1262 provides that GSP(s) or alternative plans are now part of the “substantial evidence” that may support a determination of whether sufficient water supplies will be available to serve the proposed project in addition to existing and planned future uses.

While SB 1262 codifies one way that SGMA now relates to WSAs and WVs, many other questions remain. For example, the extent to which GSPs and alternative plans prepared under SGMA must be considered in Urban Water Management Plans has not been addressed. Furthermore, the relationship between water supply “sufficiency” (for purposes of WSAs, WVs, and CEQA review) and groundwater “sustainability” (for purposes of SGMA) will need to be harmonized, either by statute or at the hand of lead agencies, GSAs and land use practitioners. To that end, the parallel — yet potentially conflicting — conclusions of GSPs, UWMPs, WSAs, WVs, CEQA documents, and other water supply analyses may lead to tension or evidentiary disputes with regard to project approvals and land use decision making.

SB 1262 helps identify the uncertainties that will persist as SGMA unfolds and relates to California’s other water supply planning laws in the coming years.

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