In conjunction with the release of [California’s Groundwater Update 2020](https://data.cnra.ca.gov/dataset/caglw_update2020), DWR has compiled a comprehensive list of the official basin boundary descriptions for all of California’s 515 groundwater basins. These descriptions were originally developed by DWR as part of California’s Groundwater (B-118) Update 2003 and have since been updated for some groundwater basins as a result of the 2016 and 2018 [Basin Boundary Modifications](https://water.ca.gov/Programs/Groundwater-Management/Basin-Boundary-Modifications). To make locating descriptions easier, they have been organized by region which is determined by the first number of the basin number (i.e. 1-XXX). The original basin descriptions developed for California’s Groundwater (B-118) Update 2003 also included summaries of the hydrologic and hydrogeologic setting, groundwater storage capacity and water budget, groundwater level and quality trends, well yields, basin management, and references. This additional information contained in the basin descriptions will now be referred to as “basin reports” and are still available [online](https://data.cnra.ca.gov/dataset/bulletin-118-update-2003-basin-reports) as part of the [Bulletin 118 - Update 2003](https://data.cnra.ca.gov/dataset/california-s-groundwater-bulletin-118-archive/resource/5fc7e39c-34e7-433e-9dbe-ff93ce76787f) report.

In conjunction with the release of [California’s Groundwater Update 2020](https://data.cnra.ca.gov/dataset/caglw_update2020), DWR has compiled a comprehensive list of the official basin boundary descriptions for all of California’s 515 groundwater basins. These descriptions were originally developed by DWR as part of California’s Groundwater (B-118) Update 2003 and have since been updated for some groundwater basins as a result of the 2016 and 2018 [Basin Boundary Modifications](https://water.ca.gov/Programs/Groundwater-Management/Basin-Boundary-Modifications). To make locating descriptions easier, they have been organized by region which is determined by the first number of the basin number (i.e. 1-XXX). The original basin descriptions developed for California’s Groundwater (B-118) Update 2003 also included summaries of the hydrologic and hydrogeologic setting, groundwater storage capacity and water budget, groundwater level and quality trends, well yields, basin management, and references. This additional information contained in the basin descriptions will now be referred to as “basin reports” and are still available [online](https://data.cnra.ca.gov/dataset/bulletin-118-update-2003-basin-reports) as part of the [Bulletin 118 - Update 2003](https://data.cnra.ca.gov/dataset/california-s-groundwater-bulletin-118-archive/resource/5fc7e39c-34e7-433e-9dbe-ff93ce76787f) report.

This dataset includes the official groundwater basin boundary descriptions for California's 515 groundwater basins. To make locating descriptions easier, they have been organized by region. This resource contains descriptions for basins that start with the number nine (9-XXX) indicating they are located in the San Diego Region.

This dataset includes the official groundwater basin boundary descriptions for California's 515 groundwater basins. To make locating descriptions easier, they have been organized by region. This resource contains descriptions for basins that start with the number nine (9-XXX) indicating they are located in the San Diego Region.

This dataset includes the official groundwater basin boundary descriptions for California's 515 groundwater basins. To make locating descriptions easier, they have been organized by region. This resource contains descriptions for basins that start with the number nine (9-XXX) indicating they are located in the San Diego Region.

This dataset includes the official groundwater basin boundary descriptions for California's 515 groundwater basins. To make locating descriptions easier, they have been organized by region. This resource contains descriptions for basins that start with the number five (5-XXX) indicating they are located in the Sacramento River Region

This dataset includes the official groundwater basin boundary descriptions for California's 515 groundwater basins. To make locating descriptions easier, they have been organized by region. This resource contains descriptions for basins that start with the number five (5-XXX) indicating they are located in the Sacramento River Region

This dataset includes the official groundwater basin boundary descriptions for California's 515 groundwater basins. To make locating descriptions easier, they have been organized by region. This resource contains descriptions for basins that start with the number three (3-XXX) indicating they are located in the Central Coast Region

This dataset includes the official groundwater basin boundary descriptions for California's 515 groundwater basins. To make locating descriptions easier, they have been organized by region. This resource contains descriptions for basins that start with the number three (3-XXX) indicating they are located in the Central Coast Region

This dataset includes the official groundwater basin boundary descriptions for California's 515 groundwater basins. To make locating descriptions easier, they have been organized by region. This resource contains descriptions for basins that start with the number seven (7-XXX) indicating they are located in the Colorado River Region