Groundwater Sustainability Agencies

The Sustainable Groundwater Management Act (SGMA) established a new structure for managing California’s groundwater resources at the local level by local agencies. SGMA required Groundwater Sustainability Agencies (GSAs) to form in the State’s high- and medium-priority basins and subbasins by June 30, 2017. Over 260 GSAs in over 140 basins were formed by SGMA’s initial planning milestone. However, as SGMA continues to be implemented and the priorities and boundaries of some basins change, new GSAs will be formed, and existing GSAs may want to reorganize, consolidate, or withdraw from managing in all or part of a basin. All GSA formation notifications are managed on DWR’s SGMA Portal.

For basins that received a new high- or medium-priority designation in 2019, local agencies overlying those basins will have two years from the date of reprioritization to either establish a GSA or submit an Alternative plan. The Water Code states that a GSA shall have five years from the date of reprioritization to be managed under a Groundwater Sustainability Plan (GSP). The planning deadline for California’s first round of GSPs is January 31, 2020, for basins subject to critical conditions of overdraft, and January 31, 2022, for all other high- and medium-priority basins.

DWR revised its GSA Frequently Asked Questions and GSA Formation Notification Guidelines documents in May 2019 to address updates to SGMA and the modification of basin boundaries. The revised documents are included below in the Publications section of this webpage. A list of GSAs that have been affected by a basin boundary modification is also included below.

Agency Roles

A legislative intent of SGMA is to recognize and preserve the authority of cities and counties to manage groundwater according to their existing powers. As a result, local governments play an important land-use and water-management role in California. SGMA assigns different roles to DWR, the State Water Resources Control Board, local agencies, and counties related to GSA formation. Those roles are summarized below.