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If you live in the central San Joaquin Valley, there’s a chance your tap water is unsafe to drink.

Nearly 180,000 people in the region get their water from systems that do not meet drinking water standards — and it’s hard, as a resident, to learn more and find out what to do to keep yourself and your family safe.

That’s why The Fresno Bee created a guide to the region’s drinking water, including:

With these tools, you can just type in your address to find out where your water comes from, if your water is considered safe to drink, how to protect yourself if the water is unsafe, and whom to contact for more information or to express your concerns.

These tools provide information about 283 community water systems in Madera, Fresno, Tulare and Kings counties. Unfortunately, data on private wells is not included because the information is unavailable or does not exist. The state does not regulate private wells.

Community water systems are generally owned and operated by cities, utilities, schools or water agencies and regulated by Regional Water Quality Control boards. If you or your landlord pays a water bill, you likely receive water from a community water system and will be able to learn about your water, using these tools.

How to use The Fresno Bee guide to drinking water

Use the map below to find out if your water system is in compliance with state health standards. To use the tool, enter your address into the search function in the upper left corner. Information about your water system will appear on the left column of the map. Or, use a searchable database if you know the name of the system you want to look up.

Information in the map is the most recent data available from the State Water Boards’ Drinking Water Database, which is updated quarterly.

Keep in mind that the safety of your drinking water can change quickly. And, even if your water system is in compliance with drinking water standards, it may still contain unsafe and harmful toxins.

Library of contaminants: Once you’ve learned if your water is contaminated, use this tool to learn how to protect yourself and your family.

Click here to load this Caspio Cloud Database
Cloud Database by Caspio

What does it mean to be in compliance?

Several drinking water systems in the central San Joaquin Valley don’t meet state drinking water standards because they have unsafe levels of toxic chemicals.

The State Water Resources Control Board regulates public drinking water systems for maximum contaminant levels (mcl) for 29 different chemicals to protect public health.

If your drinking water system is out of compliance, that means water quality testing found a level of one or more contaminants above the MCL in your water and may pose a health risk.

Dozens of community water systems that are out of compliance are in the process of being fixed. The various communities have either received funding or are in the application process to receive funding to pay for projects to make the water safer. Some are working to install water filtration systems, and others plan to dig new wells. Those projects often take years.

Even if your water system is in compliance with state standards, the water might still contain harmful contaminants. That’s because whatever contaminants in your water may be at levels below to MCL. There may also be harmful contaminants in your water from the plumbing in your home.

Where does your water come from?

There are two primary sources of drinking water for central San Joaquin Valley residents: groundwater that flows in underground aquifers and surface water, a term that describes water from snow runoff that flows into rivers and streams and is delivered to cities through canals.

The main rivers that provide drinking water to the central San Joaquin Valley are:

  • The San Joaquin River. Water from the river is stored behind Friant Dam at Millerton Lake and sent to the cities of Fresno, Clovis, Orange Cove, Lindsay, Strathmore, unincorporated Millerton New Town (via Fresno County CSA 34), and Tesoro Viejo via the Friant-Kern and Madera Canals

  • The Kings River. Water from the river is stored behind Pine Flat Dam and sent to the cities of Fresno and Clovis via Fresno Irrigation District canals

  • The State Water Project. Water from the Sacramento-San Joaquin River Delta is stored behind San Luis Dam and conveyed to the cities of Huron, Coalinga, Avenal, and unincorporated El Porvenir, and Cantua Creek, via the California Aquaduct. The Tranquility Public Utilities District, which serves unincorporated Tranquility, accesses this water through canals operated by the James Irrigation District

Nearly 60% of residents in the central San Joaquin Valley live in a water district that relies fully on groundwater for its drinking water supply. When groundwater levels drop, or if a well is found to be contaminated, they don’t have an alternative water supply — except to drill new wells, which can be expensive.

Communities that rely fully on surface water do not necessarily have more water reliability. Nearly 25% of all water districts in the region that rely on surface water are out of compliance with state water quality standards.

The Central Valley’s toxic water crisis

A quarter of all community water systems in the region do not meet state and federal drinking water standards, sometimes because they are polluted from agriculture or development. Sometimes the problem is from contaminants that occur naturally, but become concentrated at high levels when the water table drops from over-pumping.

Most systems with unsafe drinking water are in small towns or rural areas. Often, smaller communities lack the resources to address the problem because they have fewer rate payers, and their systems are more vulnerable to pollution because there are fewer options to find clean water when there is a problem.

The larger cities of Fresno, Visalia, Clovis and Madera all currently provide water that meets state and federal drinking water standards. Each of those cities have found contamination in their water systems in the past, but they were able to treat the water or turn off wells that are contaminated, or mix it with clean water to dilute the pollution.

That hasn’t been the case in several moderate-sized cities.

Water service in Tulare, Lemoore, Parlier, Lindsay and Kingsburg currently fails to meet drinking water standards due to contamination. Each of those systems serve populations larger than 10,000 people.

Other resources for California drinking water

State Water Board exceedance and compliance status tool provides statewide information about water systems, including the results of recent water quality tests.

State Water Board drinking water systems with violations tool provides detailed information about water systems, including the amount of state money allocated for projects.

CalEPA and OEHHA Office of Environmental Health Hazard Assessment community water systems tool provides information about system compliance, water supply vulnerability and affordability.

Community Water Center drinking water tool provides information about groundwater supply and quality, potential impacts from future drought, how to get involved in groundwater management decisions.

This project was made possible with support from the Central Valley Community Foundation and the Local Government Commission through the S.D. Bechtel, Jr. Foundation Community Foundation Water Initiative.

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