COMMITTEE AGENDA MEMORANDUM
Water Supply and Demand Management Committee
Government Code § 84308 Applies: Yes ☐ No ☒
(If “YES” Complete Attachment A - Gov. Code § 84308)
SUBJECT: title
Receive an Update on Groundwater Basins Managed by Valley Water and Compliance with the Sustainable Groundwater Management Act.
End
RECOMMENDATION: Recommendation
Receive an update on the groundwater basins managed by Valley Water and compliance with the Sustainable Groundwater Management Act.
Body
SUMMARY:
Under California’s Sustainable Groundwater Management Act (SGMA), Valley Water serves as the exclusive Groundwater Sustainability Agency (GSA) and has a Department of Water Resources (DWR) approved Alternative to a Groundwater Sustainability Plan (Alternative Plan) for the Santa Clara and Llagas subbasins that are entirely within Santa Clara County. Additionally, Valley Water serves as a GSA with San Benito County Water District (SBCWD) and has a DWR approved Groundwater Sustainability Plan (GSP) for the North San Benito Subbasin, which covers small areas of Santa Clara County.
Valley Water staff last updated the Water Supply and Demand Management Committee (Committee) on February 23, 2026 with a schedule and outreach plan for the required periodic evaluation of the Alternative Plan that is due to DWR by December 17, 2026. Since that Committee meeting, staff have submitted to DWR the required Annual Water Year Report (Annual Report) before the April 1 regulatory deadline. The Annual Report shows continued healthy and sustainable groundwater conditions in the Santa Clara and Llagas subbasins.
This Committee update summarizes progress on the periodic evaluation of the Alternative Plan for the Santa Clara and Llagas subbasins, including findings from an analysis of reported dry wells during the 2020-2022 drought. Staff will also share an update on the North San Benito Subbasin.
Santa Clara and Llagas Subbasins
Staff are finalizing technical analyses and incorporating DWR recommended actions into the periodic evaluation of the Alternative Plan to improve plan implementation and facilitate DWR evaluation. For example, staff analysis of reported dry wells during the 2020-2022 drought show that nine wells within Santa Clara County were reported dry, including only 0.07% (4 of 6,130) of the total active and standby water supply wells in the Santa Clara and Llagas subbasins. All nine were domestic wells, including one well in the Santa Clara Subbasin, three in the Llagas Subbasin, four outside the subbasins, and one with no location information. No agricultural or municipal and industrial (M&I) supply wells were reported dry. Similar to the 2012-2016 drought, the reported dry wells are nearly all located along the subbasin boundary or outside the subbasin where natural geologic conditions result in relatively low groundwater storage and groundwater levels that are more vulnerable to pumping stress under drought conditions. The very small percentage and location of reported dry wells indicate that Valley Water’s management practices maintain sustainable groundwater conditions, even during drought. Valley Water provides information to assist well owners, including resources for dry wells on the Wells and Well Owners webpage (<https://www.valleywater.org/contractors/doing-businesses-with-the-district/wells-well-owners>).
As work on the periodic evaluation of the Alternative Plan progresses, staff will update the Committee and engage interested parties through outreach, including email updates, social media posts, and public meetings. A public meeting will be held in the late summer and a public review of the draft periodic evaluation is expected to be available in late summer/early fall 2026 to solicit public input prior to consideration by Valley Water Board of Directors in late fall 2026.
North San Benito Subbasin
Valley Water shares GSA responsibilities with SBCWD for the North San Benito Subbasin, which is primarily located in San Benito County. The periodic evaluation of the DWR approved GSP is being led by SBCWD, including all technical analyses. Valley Water staff are supporting the evaluation and update, including serving on the Technical Advisory Committee (TAC). The second TAC meeting was held at the SBCWD on March 26, 2026.
As work on the GSP progresses, staff will update the Committee and engage interested parties. A public review of the draft GSP update for the North San Benito Subbasin is expected to be available in early fall 2026 to solicit public input prior to consideration by both the SBCWD and Valley Water Board of Directors in fall 2026.
ENVIRONMENTAL JUSTICE IMPACT:
There are no environmental justice impacts associated with this item.
ATTACHMENTS:
Attachment 1: PowerPoint
UNCLASSIFIED MANAGER:
Manager
Gregory Williams, 408-630-2867