A new California drinking water rule targeting chromium-6 may carry a heavy price tag for Coachella Valley residents.
According to the Coachella Valley Independent, meeting the requirement could cost five of the region's six water providers more than $525 million combined, with at least some of that expense potentially ending up in customer bills.
What's happening?
An April 2024 rule from California's State Water Resources Control Board set a 10-particles-per-billion cap for chromium-6 in delivered drinking water. To comply, most Coachella Valley agencies said they need to quickly expand infrastructure by adding treatment systems, wells, and pipelines.
The Coachella Valley Water District, the area's largest provider, says 34 of its 96 drinking water wells are affected.
Lorraine Garcia, the district's communication manager and public information officer, said, "This has been in the works for about 25 years."
She added, "And there's been a lot of conflict."
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Estimated costs are also substantial at other agencies. The Indio Water Authority said it will need about $130 million to address 13 affected wells, Mission Springs Water District expects roughly $25 million in costs, and Myoma Dunes Mutual Water Company estimates compliance will run between $10 million and $15 million.
Why does it matter?
State regulators classify chromium-6 as a carcinogen, and the Coachella Valley Independent reported that California is the only state with a drinking water standard specifically for it.
Residents could feel the impact through higher rates. Garcia said the Coachella Valley Water District's projected cost has climbed from earlier estimates to about $350 million, and that the agency will likely need a new cost-of-service study to determine what customers may ultimately pay.
Not every water system is in the same position. Desert Water Agency, which serves Palm Springs and nearby communities, said it already complies with the standard.
Victoria Llort, the agency's public affairs and conservation director and public information officer, wrote, "The agency has not needed to make operational changes as a result of the chromium-6 regulation."
What's being done?
Even while earlier chromium-6 standards were being challenged in court, water agencies across the valley spent years preparing. The current deadlines depend on system size: systems serving more than 10,000 customers must comply by Oct. 1, 2026; systems serving 1,000 to 9,999 customers by Oct. 1, 2027; and systems with fewer than 1,000 customers by Oct. 1, 2028.
Some providers have already taken affected wells offline as they evaluate treatment options.
Marion Champion, assistant general manager of Mission Springs Water District, wrote, "We have been open and transparent throughout this process by holding community workshops, creating a dedicated chromium-6 information section on our website, and regularly providing updates."
Agencies are now awaiting state approval for compliance plans they submitted in 2025 or early 2026.
Garcia said providers are prepared to move ahead once those approvals arrive.
"We're still in preparation time to get these projects going," Garcia said. "Other agencies are in the same situation — ready to move forward, but still needing to be approved."
She also said the contamination is not tied to a new source.
"This is all naturally occurring chromium," Garcia said. "It's been here since we've all been here, and even before that. The challenge is the 10 parts per billion MCL. That's not just a challenge for Coachella Valley Water District; it's a challenge across the entire state."
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