Attorney General Bonta Issues Enforcement Advisory on Landlord Compliance with Domestic Well Testing Requirement

1. Press Release
2. Attorney General Bonta Issues Enforcement Advisory on Land… Thursday, March 12, 2026 Contact: (916) 210-6000, agpressoffice@doj.ca.gov OAKLAND – California Attorney General Rob Bonta today issued an enforcement advisory letter to landlords whose properties are located within service areas covered by applicable well testing programs. The letter promotes awareness of and compliance with Assembly Bill 2454 (AB 2454), authored by Assemblymember Alex Lee (D-Milpitas), which requires landlords to participate in free water testing and treatment programs for domestic wells, benefitting environmental justice communities in the Central Valley, Central Coast, and other rural areas with vulnerable drinking water supplies.

“Access to safe drinking water is a fundamental human right. Everyone deserves clean, safe water in their home. Without systematic testing, contamination can remain hidden, leaving households unknowingly exposed and cut off from solutions that already exist,” said Attorney General Rob Bonta. “AB 2425 ensures that free, accessible water testing and treatment programs are available, so no one is left in the dark about their water quality and every community has the opportunity to protect their health and well-being. I urge landlords with drinking water wells to follow the law and test their wells to provide safe drinking water to protect public health and the environment from the threat of water contamination.”

“California recognizes the universal human right to safe drinking water. But rural and disadvantaged communities that rely on domestic wells remain disproportionately exposed to contaminated water,” said Assemblymember Alex Lee. “AB 2454 protects the health of tenants who depend on well water by ensuring free and existing domestic well programs are effective, accessible, and equitable. Participating in these programs is essential to preventing exposure to toxic contaminants. We must ensure that everyone has access to clean water.”

“Protecting public health is our top priority, and a huge part of achieving that is ensuring people have information about potential health risks in their environment, especially in their homes,” said Yvonne West, Director of the Office of Enforcement for the State Water Resources Control Board. “Compliance with this new law means that tenants will get the benefit of available well testing and alternative water supply programs, at no cost to landlords. It is an important step toward strengthening the protection of public health in these communities.”

More than one million Californians rely on private domestic wells for their household water supply. According to the State Water Board’s 2025 Drinking Water Needs Assessment, nearly one-third of California’s domestic wells are at risk of failing to provide safe drinking water. Many wells have never been tested for contamination, leaving well owners and tenants with limited information about water quality. Groundwater in California contains a variety of harmful contaminants from natural, agricultural, industrial, and wastewater sources, including nitrates, arsenic, 1,2,3-trichloropropane, pesticides, hexavalent chromium, and per- and polyfluoroalkyl substances (PFAS). Long-term exposure to these water contaminants can result in adverse health outcomes, including cancer, thyroid dysfunction, and blue baby syndrome. There may also be health impacts from short-term exposure. Well testing is essential to identify unsafe conditions and guide corrective actions such as the provision of bottled water, well repair or replacement, water treatment, or connection to a regulated water system.

Alarmingly, the water quality challenges in domestic wells disproportionately impact low-income communities and communities of color. Research shows that a 10% greater Latino population is associated with a 13 to 23% greater likelihood of elevated drinking water contaminant levels. The Central Valley in particular is significantly impacted by groundwater contamination, with the State Water Board identifying the counties of Fresno, Sonoma, San Joaquin, and Tulare as having the highest number of domestic wells with water quality risks. Rural renters face further vulnerabilities because they depend on landlords to maintain wells and may not have the financial means to pay for laboratory analyses out of pocket, let alone pay for replacement water or treatment. Expanding well testing to these communities allows for access to safe drinking water, moving California towards the fulfillment of the state-recognized and codified Human Right to Water, under which “every human being has the right to safe, clean, affordable, and accessible water adequate for human consumption, cooking, and sanitary purposes.”

The enforcement advisory letter explains the provisions of AB 2454, which took effect in September 2024, requiring landlords of rental properties with domestic drinking water wells to participate in free State Water Board or regional water board-administered or funded testing programs to ensure tenants have access to safe drinking water and information about water quality.  Landlords must provide tenants with the results and interpretation guidance of domestic well testing within 10 days and participate in any available free remediation programs, such as bottled water delivery, funding for treatment systems, or connection to a safe water source. Landlords are prohibited from charging tenants any fees or increasing rent for participating in these programs. The advisory also explains that violations of the law could result in fines and penalties under the Unfair Competition Law. AB 2454 works alongside AB 664 (Lee, 2024), which requires landlords who decline consolidation with a public water system to independently ensure tenants have adequate supply of safe drinking water.

To find out if your property qualifies for a free testing program and other information about AB 2454, please visit the State Water Board’s website: https://www.waterboards.ca.gov/drinking_water/certlic/drinkingwater/private-domestic-well-testing.html.

Advisory Letter in English

Advisory Letter in Spanish

Advisory Letter in Simplified Chinese

Advisory Letter in Tagalog

Advisory Letter in Punjabi

Advisory Letter in Korean

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