COMMITTEE AGENDA MEMORANDUM
Agricultural Water Advisory Committee
Government Code § 84308 Applies: Yes ☐ No ☒
(If “YES” Complete Attachment A - Gov. Code § 84308)
SUBJECT: title
Receive Update on Valley Water’s Periodic Evaluation to its Alternative Groundwater Sustainability Plan for the Santa Clara and Llagas Subbasins and the Periodic Evaluation of the Groundwater Sustainability Plan for the North San Benito Subbasin under the Sustainable Groundwater Management Act.
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RECOMMENDATION: Recommendation
Receive an update on Valley Water’s periodic evaluation to its Alternative Groundwater Sustainability Plan for the Santa Clara and Llagas subbasins and the periodic evaluation of the Groundwater Sustainability Plan for the North San Benito Subbasin under the Sustainable Groundwater Management Act.
Body
SUMMARY:
Under California’s Sustainable Groundwater Management Act (SGMA), Valley Water serves as the Groundwater Sustainability Agency (GSA) for the Santa Clara and Llagas subbasins, which are located within Santa Clara County. Valley Water has an approved Alternative Groundwater Sustainability Plan (Alternative Plan) that describes the management of these groundwater basins.
In addition, Valley Water serves as the GSA for a very small portion of the North San Benito Subbasin that is located within Santa Clara County. San Benito County Water District (SBCWD) serves as the GSA for the vast majority of this basin. There is also an approved Groundwater Sustainability Plan (GSP) that describes the management of this basin.
Under the SGMA, GSAs must provide comprehensive periodic evaluations of their GSPs or Alternative Plans every five years.
Valley Water staff last updated the Agricultural Water Advisory Committee (Committee) on April 6, 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. This 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 periodic evaluation of the North San Benito Subbasin GSP.
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 on July 30, 2026 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’s Board of Directors in late fall 2026.
North San Benito Subbasin
Valley Water shares GSA responsibilities with SBCWD for the North San Benito Subbasin, the vast majority of which is located within San Benito County but also extends into southern Santa Clara County. The periodic evaluation of the 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 this GSP update 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 SBCWD and Valley Water’s Board of Directors in late fall 2026.
ENVIRONMENTAL JUSTICE IMPACT:
There are no environmental justice impacts associated with this item.
ATTACHMENTS:
Attachment 1: PowerPoint
UNCLASSIFIED MANAGER:
Manager
Greg Williams, 408-630-2867