Frequently Asked Questions

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:

1. Trivalent chromium (chromium-3) is the most common form of chromium. It is naturally occurring, nontoxic, and is an essential human nutrient.
2. 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.

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.

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.

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.

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.

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. 

The cost of complying with the new regulation will exceed $350 million, significantly increasing water rates.

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. 

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.

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.

CVWD routinely monitors our water system and collects more than 17,000 water samples per year. CVWD’s water meets all current state and federal drinking water quality standards and is committed to complying with the new requirements.