There are several levels of water management in California, from the community water system who may supply the drinking water to your home, to the local, regional, and state agencies who regulate water availability and quality in wells and streams. This tool identifies different local agencies that may be making decisions about groundwater in your area.
Community water systems are typically overseen by the State’s Division of Drinking Water and typically manage their own groundwater wells. For private domestic wells, local agencies will have the authority over any new groundwater well construction or changes to existing wells. Often this will be your County Department of Environmental Health.
Groundwater Sustainability Agencies (GSA) are public entities that manage how groundwater is used locally in certain parts of the state. GSAs have the power to regulate how much groundwater is pumped and by whom. GSAs are developing policies that will impact available supply for both community water system wells and private domestic wells.
According to the information you provided, your drinking water is supplied from a community water system (CWS). CWSs are publicly regulated water suppliers that serve piped, treated water to at least 25 residents or 15 connections year-round. CWS providers can include private companies, mobile home parks, city water systems, and water districts.
Some important jurisdictions in your area include:
* Your address was not found within the boundaries of a Groundwater Sustainability Agency. This means that your area may not be subject to SGMA at this time. Your area might have a voluntary groundwater management plan, contact your county to learn more.
According to the information you provided, you may be served by a private domestic well, even though your address was located within the service area of the listed community water system.
Some important jurisdictions in your area include:
* Your address was not found within the boundaries of a Groundwater Sustainability Agency. This means that your area may not be subject to SGMA at this time. Your area might have a voluntary groundwater management plan, contact your county to learn more.
According to the information you have provided, your water comes from a private domestic well.
Some important jurisdictions in your area include:
* Your address was not found within the boundaries of a Groundwater Sustainability Agency. This means that your area may not be subject to SGMA at this time. Your area might have a voluntary groundwater management plan, contact your county to learn more.
According to the information you provided, your drinking water is supplied from a community water system whose boundaries are inaccurate or not currently in our tool. To check who your community water system is, review your most recent water bill, visit the State Board’s water supplier tool or call your County Environmental Health Department. Explore the Map to learn about community water systems in your area.
Some important jurisdictions in your area include:
* Your address was not found within the boundaries of a Groundwater Sustainability Agency. This means that your area may not be subject to SGMA at this time. Your area might have a voluntary groundwater management plan, contact your county to learn more.
According to the information you provided, your drinking water is supplied from a community water system whose boundaries are inaccurate or not currently in our tool. To check who your community water system is, review your most recent water bill, visit the State Board’s water supplier tool or call your County Environmental Health Department. Explore the Map to learn about water systems in your area.
Some important jurisdictions in your area include:
* Your address was not found within the boundaries of a Groundwater Sustainability Agency. This means that your area may not be subject to SGMA at this time. Your area might have a voluntary groundwater management plan, contact your county to learn more.
According to the information you provided, it looks like your address is in an area with an unknown water provider. If you think your water is from a private domestic well, your household may be in a newer development or is missing from the state’s database of completed private domestic wells. Please check back as we will update this tool as new data becomes available.
Some important jurisdictions in your area include:
* Your address was not found within the boundaries of a Groundwater Sustainability Agency. This means that your area may not be subject to SGMA at this time. Your area might have a voluntary groundwater management plan, contact your county to learn more.
While groundwater is a resource that can be replenished, supplies can be threatened. For example, drought, climate change, and high levels of pumping can mean groundwater levels go down, causing drinking water supplies to decrease. Anticipating whether the area where you live could be impacted by future droughts and other drivers of groundwater level change is complicated. One factor that influences possible threats to your water supply is whether your drinking water comes from groundwater and/or surface water. This section can help you learn more about your water supply and whether it could be impacted by changes in groundwater levels, like what often happens during a drought.
Your community water system’s primary water source is [CWS_MAINSOURCE].
Even if your community water system’s primary source type is surface water, it could also have access to groundwater. If so, its public supply wells may be affected by changing groundwater levels. According to annual reports submitted to the state between 2013 and 2016, by [CWS_NAME], your system [CWS_AVAILSOURCES].
The homeowner of a house (or group of homes) reliant on a private domestic well is responsible for well maintenance, which includes managing both water quantity and quality.
According to available information, there are [COUNTY_WELLCOUNT] private domestic wells in your county.
The homeowner of a house (or group of homes) reliant on a private domestic well is responsible for well maintenance, which includes managing both water quantity and quality.
According to available information, there are [COUNTY_WELLCOUNT] private domestic wells in your county.
According to the information you provided, your drinking water is supplied from a community water system whose boundaries are inaccurate or not currently in our tool. To check who your community water system is, review your most recent water bill, visit the State Water Board’s water supplier tool or call your County Environmental Health Department. Then contact your service provider to learn more about your system’s water supply.
To learn about groundwater in your area Explore the Map.
Your address is in an area with an unknown water provider. According to the information you provided, your drinking water is supplied from a community water system whose boundaries are inaccurate or not currently in our tool. To check who your community water system is, review your most recent water bill, visit the State Water Board’s water supplier tool or call your County Environmental Health Department. Then contact your service provider to learn more about your system’s water supply.
To learn about groundwater in your area Explore the Map.
Your address is in an area with an unknown water provider; the tool may be missing water supply information for nearby private domestic wells. The homeowner of a house (or group of homes) reliant on a private domestic well is responsible for well maintenance, which includes managing both water supply and quality.
According to available information, there are [COUNTY_WELLCOUNT] private domestic wells in your county.
To learn about groundwater in your area Explore the Map.
This tool includes an assessment of wells in the Central Valley that could be at risk to supply issues based on different scenarios of drought-related changes in groundwater levels. The analysis includes both private domestic wells and public supply wells for community water systems that serve less than 10,000 people. To learn more about this analysis visit the Methodology. If you are served by a larger community water system and/or live outside of the Central Valley, please contact your water system, Groundwater Sustainability Agency or county with concerns about supply risks in your area.
The drought scenario analysis compares a well’s depth to three estimated groundwater level declines. The three drought scenarios are based on scaling the total groundwater level change observed during the 2012 to 2016 drought. If the groundwater levels in your area dropped 10 feet, between 2012-2016, then the 100% drought scenario has 10 feet of decline, the 75% drought scenario has 7.5 feet of decline, and the 50% scenario has 5 feet of decline. The number of impacted wells in each scenario includes any well that experiences issues because of a drop in groundwater levels including needing to lower the well’s pump, cleaning the well screen to remove sand, or replacing the well if it becomes completely dewatered or dry.
The estimated number of impacted community water system public supply wells within 1-mile of the community water system’s service area for each drought scenario are:
A zero value indicates that there were no impacts for that scenario. A missing value (·) indicates that there was insufficient data for the analysis. Explore the Map to visualize the estimated costs for each scenario.
The estimated number of impacted private domestic wells for your 1-mile squared section, for each drought scenario are:
A zero value indicates that there were no impacts for that scenario. A missing value (·) indicates that there was insufficient data for the analysis. Explore the Map to visualize the estimated costs for each scenario.
The federal Safe Drinking Water Act requires CWSs to regularly monitor for drinking water contaminants to determine if and when they are found above a Maximum Contaminant Level (MCL). If contaminant levels are above and in violation of the MCL- the highest level of a contaminant allowed in drinking water – the CWS must notify customers and correct the problem. All CWSs are also required to provide an annual water quality report to customers, called a Consumer Confidence Report (CCR). Private domestic wells are not regulated and thus are not required to monitor their water quality. Thus a homeowner of a house (or group of homes) reliant on a private domestic well is responsible for testing and treating their own well water.
This section of the Drinking Water tool can help you learn more about water quality concerns in your area. This tool currently provides water quality data for four key drinking water contaminants: Arsenic, Nitrate, 123-Trichloropropane, and Chromium VI. The MCL for each contaminant is shown in milligrams (mg) or micrograms (µg) per liter (L).
According to the California State Board’s Human Right to Water Portal, [CWS_NAME] had [CWS_MCL_VIOLATIONS] MCL violations between 2012- Aug. 30, 2019. The Human Right to Water Portal currently serves as the state’s primary location information on water system performance measures, like compliance with the Safe Drinking Water Act.
The contaminant levels displayed for your CWS are based on a nine-year average from 2005-2013, for four contaminants. The data was developed and shared by CalEPA’s Office of Environmental Health Hazard Assessment for its CalEnviroScreen 3.0 tool. As such, the data presented in this tool is not necessarily the most up-to-date and may over or underestimate current contaminant concentrations in your water. To learn more about your system’s water quality, contact your water system and ask for a copy of the most recent Consumer Confidence Report.
A zero value indicates that contaminant levels were below the detectable limit at which they can be reliably measured, and a missing value (·) indicates that the contaminant was not measured in the community water system. The 9-year average estimated value for contaminants found in the groundwater are:
Learn more about the data and methods used to estimate groundwater quality for this tool.
This tool does not have water quality information for private domestic wells located within the service area of a Community Water System. Please check back as we will continue to update this tool as new data becomes available. Explore the Map to learn about drinking water quality in your area.
To learn more about private domestic well water quality testing, health impacts of drinking water contaminants, point of use treatment options, and available funding to address your water quality concerns, visit Getting Involved.
To get the most accurate source of information on your well water quality, you should test your water. This tool provides estimates of what the groundwater water quality in your area may be, but they are not specific to your well. Instead, the tool provides water quality estimates for four contaminants averaged over multiple years (2005 to 2019) and over a large region (36 square miles).
Based on this tool’s analysis, the average estimated value for contaminants found in the groundwater near your private domestic well are:
These values are approximations based on water sampling data from untreated public water system well water and from state and federal private domestic well sampling projects. A zero value indicates that the concentration was measured below the detectable limit at which they can be reliably measured. Missing data is denoted by (·) and indicates that no water quality was sampled for this contaminant in your area. Learn more about the data and methods used to estimate groundwater quality in this tool.
The best way to learn about concentrations of contaminants in your own drinking water well is to have your water tested. To learn more about private domestic well water quality testing, health impacts of drinking water contaminants, point of use treatment options, and available funding to address your water quality concerns, visit Getting Involved.
Since your drinking water is supplied from a CWS whose boundaries and thus water quality information are not currently in our tool, in order to learn more about your system’s water quality, determine your service provider, contact them and ask for a copy of the most recent Consumer Confidence Report.
To learn about untreated groundwater in your area, browse the private domestic well water quality layers Explore the Map.
Since your drinking water is supplied from a CWS whose boundaries and thus water quality information are not currently in our tool, in order to learn more about your system’s water quality, determine your service provider, contact them and ask for a copy of the most recent Consumer Confidence Report.
To learn about untreated groundwater in your area, browse the private domestic well water quality layers Explore the Map.
Since your address is in an area with an unknown water provider, the tool is missing water quality information for nearby private domestic wells. To learn about untreated groundwater in California, browse the private domestic well water quality layers Explore the Map.
To learn more about private domestic well water quality testing, health impacts of drinking water contaminants, point of use treatment options, and available funding to address your water quality concerns, visit Getting Involved.