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Chromium-6 Information
California has adopted a more stringent drinking water standard
California is the first and only state in the nation to set a drinking water standard for naturally occurring chromium-6. The adopted Maximum Contaminant Level (MCL) is 10 parts per billion (*ppb). In other states, the limit for total chromium is 100 ppb. *10 ppb is about 10 drops in an Olympic-sized pool, which holds about 660,430 gallons.
Your tap water is still safe to drink and can be used for cooking and other purposes. The only change is that the state has implemented a stricter regulation. Our water has not changed. Chromium exists in groundwater across California. The state is regulating chromium-6 at more stringent levels for potential health impacts, not for any immediate health risks.
CVWD is committed to meeting the regulation, but it will take time to construct treatment facilities, remove wells from distribution, and drill new wells. On October 13, 2025, CVWD submitted a compliance and implementation plan, including a timeline, to the California State Water Resources Control Board - Drinking Water Division for approval.
Customer Notices: These notices will be posted on this webpage quarterly, per State regulations, until we can meet the 10 ppb standard.
- Cove Communities Water System (Rancho Mirage, Palm Desert, Thousand Palms, Indian Wells, La Quinta, Mecca, Bombay Beach, North Shore, Hot Mineral Spa, and portions of Cathedral City, Bermuda Dunes, Indio, Oasis, Thermal, Valerie Jean, and Riverside County)
- January 2026 Notice (PDF)
- Aviso del Enero 2026 (Spanish PDF)
- November 2025 Notice (PDF)
- Aviso del Noviembre 2025 (Spanish PDF)
- ID-8 Water System (Sky Valley, Indio Hills, and portions of Desert Hot Springs)
- January 2026 Notice (PDF)
- Aviso del Enero 2026 (Spanish PDF)
- November 2025 Notice (PDF)
- Aviso del Noviembre 2025 (Spanish)
For questions, please contact our Water Quality Division at 760-398-2651, extension 2515, or by email at WQInquiries@cvwd.org.
- What is hexavalent chromium, or chromium-6 or cr6?
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Chromium is a naturally occurring metallic element found in the Earth’s crust, including in rocks and sediments of the Coachella Valley.
There are two primary forms of chromium:
- Trivalent chromium (chromium-3) is the most common form of chromium. It is naturally occurring, nontoxic, and is an essential human nutrient.
- Hexavalent chromium (chromium-6) can form during the weathering of rocks and sediments that have chromium-3. Exposure to chromium-6 over many years has been linked to potential health concerns.
Figure 1. Chromium-6 can form during the weathering of rocks and sediments that contain chromium-3.
- Is it safe to drink my water?
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Your tap water is still safe to drink. The only change is that the state has implemented a stricter regulation. The valley's water has not changed. Chromium exists in groundwater across California. The state is regulating chromium-6 at more stringent levels for potential health impacts, not for any immediate health risks.
The federal drinking water standard, used by other states, for total chromium is 100 parts per billion. The California drinking water standard for total chromium is 50 ppb, including chromium-3 and chromium-6.
California’s adopted 10 ppb MCL is the nation's only drinking water standard for chromium-6.
- What has changed?
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In 2014, California adopted a new drinking water regulation specific to chromium-6 that was lower than the total chromium limit, setting a limit of 10 ppb. In 2017, the Court invalidated the 2014 MCL for chromium-6, ruling that the economic analysis used to set the Maximum Contaminant Level (MCL) was insufficient.
On April 17, 2024, after completing a new economic analysis, California again adopted the chromium-6 MCL at the initially proposed limit of 10 ppb. The MCL became effective on October 1, 2024.
The chromium-6 MCL is again being challenged in court for inadequate economic analysis and exploration of alternatives, and for failing to consider its impact on California’s Human Right to Water Policy.
- Why did I get a notice about chromium-6
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CVWD is required to notify the public, using the state-required language, when the annual average of quarterly samples exceeds the chromium-6 MCL of 10 ppb. CVWD is also required to provide quarterly notices until all impacted drinking water supplies comply with the adopted chromium-6 regulation.
- How much chromium-6 is in our water?
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The average level of naturally occurring chromium-6 in CVWD’s wells is 9.4 ppb, with a range of 0 to 22 ppb. The adopted standard is 10 ppb. In other states, the limit for all chromium (3 and 6) is 100 ppb. California’s MCL is the nation's only drinking water standard for chromium-6 at 10 ppb.
Recent testing shows that about one-third (33 of 92) of the wells in CVWD’s Cove system have chromium-6 levels above the state's limit of 10 ppb.
- What is CVWD doing to meet the adopted regulation?
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Our mission is to provide safe, reliable drinking water for our customers. In October 2025, CVWD submitted a Compliance Plan and timeline to the California State Water Resources Control Board, Division of Drinking Water, for review and approval, but has not received a response.
- How much will it cost to comply?
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The cost of complying with the new regulation will exceed $350 million, significantly increasing water rates.
- Are other water agencies in California impacted?
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Yes. This drinking water MCL impacts 129 water systems, which will have to spend billions of dollars for treatment, undermining water affordability across California, which is the basis for the current lawsuit.
The chromium-6 MCL is again being challenged in court for inadequate economic analysis and exploration of alternatives, and for failing to consider its impact on California’s Human Right to Water Policy.
- What makes this different from chromium-6 contamination made famous by Hollywood and court cases?
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Chromium-6 became a household name because of industrial pollution that contaminated drinking water supplies. In Hinkley, California, chromium-6 levels exceeded 1,000 parts per billion (ppb), compared with 22 ppb, the highest well with chromium-6 levels in CVWD's system.
- A California court struck down the same chromium-6 MCL in 2017. Could this happen again?
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Yes. The chromium-6 MCL is again being challenged in court for inadequate economic analysis and exploration of alternatives, and for failing to consider its impact on California’s Human Right to Water Policy. Along with many other California water providers, CVWD opposes this regulation, arguing that the State Water Resources Control Board failed to conduct the legally required public health, financial, environmental, and feasibility analysis and studies.
This drinking water MCL affects 129 water systems, which will have to spend billions of dollars on treatment, thereby undermining water affordability across California.
Resources
Download a PDF copy of the FAQ:
Domestic water well map
View the domestic water well map showing the chromium-6 concentrations and the locations of the wells.
Water quality is a top priority
CVWD employees monitor your water system and test more than 17,000 samples annually for more than 100 regulated and unregulated substances. This ensures customers receive safe drinking water that complies with all applicable state and federal regulations. Visit our Water Quality page to learn more.
Evaluation of Options to Comply with California's Chromium-6 MCL
Recorded presentation at the May 13, 2025, public board of directors meeting
Chromium-6 Preliminary Financing Options
Recorded presentation to the CVWD Finance Committee on July 28, 2025