Groundwater in California – California Public Policy Institute

SOURCE: Prepared by the authors using information from the California Department of Water Resources (DWR): SGMA Data Viewer, Reference Layers, and SGMA Portal.

COMMENTS: The map shows that SGMA has 129 designated basins that account for the majority of groundwater use in California. This includes 21 ‘critical overdraft’ river basins, most of which had to submit their sustainability plans in 2020, and 66 other high and medium priority river basins that submitted their plans in 2022. The formally managed areas are those which were already formally managed in place before SGMA. This includes the 34 groundwater basins covered by the ruling that have court-appointed water managers and are exempt from SGMA requirements, as well as 10 areas with other management arrangements, such as special management districts, that have approved alternative plans under SGMA (two of them – Pajaro Valley and Borrego Springs – are considered severely overdrawn but are shown as formally managed areas). For the adjudicated catchments, the boundaries of the subareas are shown on the map.