Valley Water's Board of Directors will hold a public hearing Nov. 10 on a draft plan for managing local groundwater basins. Groundwater supplies roughly half the county's water.
Palo Alto normally receives its drinking water from the San Francisco regional water system, while local groundwater wells provide emergency supplies, according to the city’s One Water Plan.
The 2026 Groundwater Management Plan guides how the agency protects, replenishes and sustains local groundwater. The board could adopt the plan at the same meeting, according to a Valley Water news release. If adopted, the plan will be submitted to the California Department of Water Resources (DWR) by Dec. 17.
The hearing is scheduled for 1 p.m. at Valley Water headquarters, 5750 Almaden Expressway in San Jose. Remote access will be available via Zoom. Agenda materials will be posted on the Valley Water board's meeting calendar.
Palo Alto is represented on the Valley Water board by Rebecca Eisenberg.
What the plan covers
Valley Water serves as the Groundwater Sustainability Agency for the Santa Clara and Llagas subbasins and part of the North San Benito Subbasin. California's Sustainable Groundwater Management Act (SGMA) requires local agencies to manage groundwater sustainably.
The state approved Valley Water's existing groundwater plan in 2019 and its first five-year update in 2024. The updated 2026 version incorporates state recommendations for closer coordination with neighboring basins and better alignment of monitoring data with state systems, according to the agency.
Why it matters locally
Groundwater basins beneath Santa Clara County hold more water than all 10 of the county's surface reservoirs combined, according to Valley Water's groundwater information page. The resource is critical during droughts, when imported surface water supplies can shrink.
The agency has managed groundwater since 1929. Historically, excessive groundwater pumping caused parts of the county to sink nearly 14 feet, according to Valley Water’s subsidence history. Seawater spread into 57 square miles of shallow aquifers near San Francisco Bay. By the 1970s, Valley Water's efforts had stopped overdraft and prevented seawater intrusion from spreading farther inland, according to the news release.
Groundwater recharge and reservoir operations also sustain about 3,370 acres of wetlands, streams, springs and deep-rooted vegetation across the county, the agency said.
