GREELEY, Colo. (KDVR) — The Cameron Peak Fire continues to impact life in northern Colorado, even months after being extinguished, and is posing challenges for the area’s water supply.

Portions of the Poudre River have turned brown, even black, as ash and debris from the burn scar is washed downstream.

That water has been so dirty, water utilities have had to pass on some of it over the past few weeks, saying treatment isn’t viable.

“The challenge for us is we can’t treat that really ashy, really high-sediment water,” said Sean Chambers, with Greeley Water and Sewer. “We have to let it go by our diversion structure, and then we switch to reservoir water.”

Chambers said crews captured a photo of jet black water in late May and said water levels have slowly cleared up since then.

He said even small rain events can cause major impacts on water quality down stream.

“We’re receiving ash, and debris, and sediment, all coming into the river, and then it’s being carried downstream,” he says. “Rain events only exacerbate that challenge.”

Chambers said he’s confident Greeley residents won’t see an impact in their drinking supply this summer, thanks to large reserves held in places like Horsetooth Reservoir.

But he said it could be a challenge for years to come.

“We’re very concerned that the frequency is going to increase, and we’ll be tuning off the river diversion much more often,” he said. “When you see water like that, you can’t treat it, at least not cost-effectively. So that’s when we shut off the intake, and we switch to the water in storage.”

Chambers and Greeley Water have been working with Fort Collins and Northern Water to secure additional funding for wildfire-impact mitigation and watershed restoration.

“You can imagine with the burn area at more than 200,000 acres, there’s a lot of mitigation to be done,” Chambers said. “The more vegetation we can get in, the more roots we get established, the less problem we have in the long term.”