The California Department of Water Resources has released an interim update of Bulletin 118, the state’s primary groundwater information resource. The update addresses time-sensitive information that agencies will need to comply with the Sustainable Groundwater Management Act. The Act, known as SGMA, took effect in 2015. It requires local agencies to undertake significant groundwater management activities on an aggressive schedule for basins designated by DWR as high- and medium-priority. The interim update includes the following changes to the 2003 version:

Additional groundwater basins in critical overdraft conditions.

• Recent modifications to basin and subbasin boundaries.

The interim update is expected to be further amended in late 2017 to address potential changes in the priority ranking of groundwater basins. A comprehensive update is scheduled for 2020. Bulletin 118 and related information can be found here.

Critically Overdrafted Basins

Under SGMA, DWR was required to identify basins and subbasins subject to critical overdraft conditions. The final list of 21 critically overdrafted basins, available here, is now incorporated into the interim Bulletin 118.

The list is significant because, under SGMA, high- and medium-priority basins that are also subject to critical conditions of overdraft as classified in Bulletin 118 must be covered by Groundwater Sustainability Plans or an alternative to a GSP by Jan. 31, 2020 – two years earlier than other high- and medium-priority basins.

Basin Boundary Modifications

SGMA also included provisions enabling local agencies to request basin boundary modifications to reflect scientific and jurisdictional considerations. DWR approved 39 boundary modification requests earlier in 2016. They are summarized in this listing. DWR also made technical adjustments to basin boundaries to correct known inconsistencies and errors.

All of these adjustments are now incorporated into the interim update to Bulletin 118. The boundary changes, which will be reflected in the boundaries of new GSAs, were made with the goal of improving coordination and promoting statewide sustainable groundwater management.

Basin Reprioritization

The update of Bulletin 118 basin boundaries has triggered another requirement in SGMA that DWR undertake a fresh prioritization process for high-, medium-, low- and very low-priority basins. This reassessment is currently underway and will include future public meetings and workshops. The process will conclude in late 2017. At that time, the interim update of Bulletin 118 will be amended to include DWR’s approach for the basin reprioritization project and any changes that result.