Groundwater Monitoring

As nearly half the county's water supply comes from groundwater, the district actively monitors groundwater to assess groundwater conditions and to ensure groundwater resources are sustained and protected.

The district monitors regional groundwater quality to evaluate current conditions and identify potentially adverse trends so that appropriate action can be taken to protect groundwater resources. The district also monitors the quality of water used for groundwater recharge to ensure groundwater quality is protected. Groundwater quality data is summarized in the district's Annual Groundwater Report and Groundwater Quality Summary.

• Recent Annual Groundwater Reports and Groundwater Quality Summaries

The district actively monitors groundwater elevations to evaluate current groundwater conditions and land subsidence, optimize recharge efforts, assess groundwater storage, and support groundwater management efforts. The district also surveys hundreds of benchmarks each year to determine if there has been any change in the land surface elevation.

Recent monthly reports on water level conditions are available below. For prior reports, please contact the district’s Groundwater Hotline at (408) 630-2300. You can also directly search groundwater elevation data for specific areas using the link below. 

• Access groundwater elevation data