About Valley Water's groundwater management efforts
Santa Clara County’s groundwater basins are an important but unseen part of our water supply. In fact, these basins hold more water than all 10 of our surface reservoirs combined, and nearly half of all water used comes from groundwater. Groundwater basins are naturally replenished by rainfall and other sources, but pumping far exceeds natural recharge. For many decades, Valley Water has managed groundwater and surface water to ensure continued sustainable water supplies.
As the groundwater management agency for the Santa Clara County, Valley Water works to safeguard groundwater by:
- Replenishing groundwater with local and imported surface water.
- Reducing demands on groundwater through treated surface water deliveries, water conservation, and water recycling.
- Monitoring groundwater and implementing programs to protect against contamination.
Valley Water's Annual Groundwater Report provides detailed information on recent groundwater conditions and activities.
- Download the 2021 Annual Groundwater Report (PDF 39 MB)
Valley Water has managed groundwater resources in Santa Clara County since 1929, and conditions have been sustainable for many decades due to Valley Water’s activities that protect and augment groundwater supplies. In 2014, Governor Brown signed the Sustainable Groundwater Management Act (SGMA) to promote the local, sustainable management of groundwater supplies. For basins designated as medium and high priority by the state, SGMA requires local Groundwater Sustainability Agencies (GSAs) to develop and implement Groundwater Sustainability Plans (GSPs) or Alternatives to achieve sustainability.
For more information about these topics, Valley Water activities, and documents related to Valley Water's Groundwater Management Plan, please visit the following page: https://www.valleywater.org/your-water/where-your-water-comes/groundwater/sustainable.
For other topics related to groundwater, please visit the links below:
- Groundwater Supply
- Groundwater Quality
- Groundwater Monitoring
- Groundwater Studies
- Groundwater Benefit Zone Study
- Free testing for domestic well owners
- Certified Laboratories