County Groundwater Basin Priority Changes

June 12, 2018

The Department of Water Resources (DWR) recently released a draft prioritization of groundwater basins as required by the Sustainable Groundwater Management Act (SGMA), including three San Luis Obispo County groundwater water basins. The Los Osos Valley Groundwater Basin and the Atascadero Groundwater Sub-basin have been lowered from high-priority basins to very low-priority basins; The San Luis Obispo Valley Groundwater Basin has been raised from medium-priority to high-priority.

The 2018 SGMA Basin Prioritization is scheduled to be finalized by fall 2018 after a 60 day public comment period that starts today and runs through July 18, 2018.

If the San Luis Obispo Valley basin is prioritized as high, it will be required to have a Groundwater Sustainability Plan in place by 2020 (instead of 2022). The county is still proceeding with a basin boundary modification request for the Los Osos Valley basin, regardless if it is prioritized as very-low and not fall under SGMA requirements. It is not yet known what the Atascadero sub-basin Groundwater Sustainability Agency (GSA) will do if the draft prioritization is approved.

Basins throughout the state are ranked high-, medium-, low-, or very low-priority. Basins ranking high- or medium-priority are subject to SGMA. Of the 517 groundwater basins statewide, the newly released draft prioritization identifies 109 basins as high- and medium-priority, which includes 14 basins newly ranked as high- or medium-priority. Additionally, 38 basins previously ranked as high or medium-priority are now ranked as low- or very-low priority and are no longer subject to SGMA. Draft prioritization results can be viewed using DWR’s newly developed visual application tool, the 2018 Prioritization Dashboard.

DWR will hold a public webinar May 30 to present the draft results, followed by statewide public meetings at the end of June. DWR will be taking public comments on the draft results, including additional data or information that is consistent with statewide datasets identified in the Basin Prioritization Process and Results Document.

When the 2018 SGMA Basin Prioritization is made final, the basins newly subject to SGMA must form GSAs within two years and develop GSPs within five years or submit an Alternative Plan within two years. DWR provides a wide-variety of resources and services to support local agencies and GSAs in implementing SGMA.

Low- or very low-priority basins are not subject to SGMA, but are encouraged to form GSAs and GSPs, update existing groundwater management plans, and coordinate with adjacent basins to develop a new groundwater management plan. For more information or to submit a comment, please visit:

Back to Government News