Drinking Water Tool

The Drinking Water Tool provides information about the ways that communities across the state might be vulnerable to groundwater challenges that could affect their access to long-term safe and affordable drinking water. This tool tells you:

• Who manages or makes decisions about your water supply;
• Groundwater quality in the area where you live;
• Potential impacts to groundwater supply from future droughts;
• How to get involved in local groundwater management decisions.

Each year, over one million Californians are exposed to unsafe drinking water from the taps in their homes, schools, churches, parks, and community centers. Although unsafe tap water can be found in nearly every county of the state, areas like the San Joaquin Valley are disproportionately impacted. Groundwater, which is found in the spaces between the soil and rocks beneath the earth’s surface, is the primary drinking water source for over 95% of communities in the San Joaquin Valley. Many communities are 100% reliant on groundwater. Groundwater faces many threats. Contamination of groundwater from industrial and agricultural sources causes poor drinking water quality that harms the health of people consume it. Decreases in groundwater levels can cause wells to go dry.

Based on analyses developed for this tool, 1.6 million Californians live in areas served private domestic wells. Many of these residents live in the Central Valley and would be affected by future droughts. For example, we estimated that 4,500 domestic wells could be impacted in a future drought. Impacts could cost the state an estimated $115 million to remediate, present a serious public health crisis, and undermine California’s efforts to secure the Human Right to Water for everyone in our state.

As Groundwater Sustainability Agencies develop and revise Groundwater Sustainability Plans under the Sustainable Groundwater Management Act,  decision makers must address the needs of vulnerable communities. For groundwater to be managed and used responsibly and equitably, Californians need to know which communities are most vulnerable and use that information to help drive groundwater management policies led by those most impacted. We created the Drinking Water Tool to provide access to this information.

Use the tools below to learn more about groundwater issues in your area and throughout California.

Visit Getting Involved to learn how to use this information to take action in your community. To provide feedback, contact the Community Water Center.