The California Department of Water Resources (DWR, Department) today released determinations for groundwater sustainability plans in 16 basins. This announcement marks another major milestone for the Sustainable Groundwater Management Act (SGMA) – completion of initial groundwater sustainability plan (GSP) reviews for all high and medium priority groundwater basins that were required to submit plans.

Of the 16 basins, the Department issued an Inadequate determination to one subbasin and determinations to the remaining 15 basins that their GSPs are Approved. In its technical review of the revised GSPs, the Department found sufficient action has not been taken to address one or more deficiencies in the Pleasant Valley Subbasin in Fresno County. The Inadequate Basin is now under State intervention, overseen by the State Water Resources Control Board under SGMA.

DWR has approved plans for the following basins: Antelope, Bowman, Los Molinos, and Red Bluff in Tehama County; Big Valley in Lassen and Modoc Counties; Butte Valley in Siskiyou County; Carpinteria in Santa Barbara and Ventura Counties; Colusa in Glenn and Colusa Counties; Corning in Glenn and Tehama Counties; Fillmore and Piru in Ventura County; Modesto in Stanislaus and Tuolumne Counties; Montecito in Santa Barbara County; Tulelake in Modoc and Siskiyou Counties; and Turlock in Merced and Stanislaus Counties. These plans are approved with recommended corrective actions that the groundwater sustainability agencies (GSAs) will need to address in their next plan update. DWR’s approval of a GSP identifies that the plan substantially complies with the GSP Regulations and SGMA law, relying upon the best available science and information, and whether implementation of the plan is likely to achieve the basin’s sustainability goal over the 20-year planning horizon of SGMA.

The assessments can be viewed on the SGMA Portal. For additional information on these GSP assessments, DWR has prepared a press release providing an overview of these assessments and a GSP Evaluation fact sheet summarizing SGMA’s determination pathways for GSPs. SGMA lays out a process for continuous improvement, gathering information to fill data gaps, updating plans, carrying out projects and actions, and promoting science-based adaptation.

DWR encourages all SGMA interested parties to review the assessments, and related materials, accessible on our GSP webpage. For any SGMA-related questions, please email DWR at: sgmps@water.ca.gov.