DENVER – Residents of the Ouray and Ridgway communities are concerned about a discoloration of the Uncompahgre River, similar to the Animas River after the August Gold King Mine spill.
With iconic images still fresh of the Animas turning mustard orange after an Environmental Protection Agency-contracted team inadvertently released an estimated 3 million gallons of old mining sludge, the communities have wondered why their Uncompahgre River turned a similar color.
In the case of the Gold King spill, the Animas tested for initial spikes in heavy metals after the incident, including lead, arsenic and copper.
The Ouray County Sheriff’s Office issued an alert on Sept. 24 notifying the public of the Uncompahgre River discoloration.
Twice a year, owners of the Ouray Hydroelectric Power Plant flush its reservoir to reduce sediment, releasing higher levels of metals.
The plant itself is not responsible for the metals because they flow downstream from natural processes and inactive mines. Flushing stirs them.
The permitting for the release is sanctioned by the Federal Energy Regulatory Commission. The state’s regulatory authority includes water-quality certification under the federal license.
The Uncompahgre Watershed Partnership, which monitors river events, pointed out that the river is not used as a residential water supply. Fish and insect populations were long damaged by high heavy-metal levels.
Still, it is unclear how the increased concentrations during flushing events affect the remaining aquatic life and recreational river users. A study from 2001 showed a jump in lead by 30 times and iron by 40 times.
“The resulting orange flow is just a highly visible symptom of a much larger problem – the multitude of abandoned mines upstream,” said the Uncompahgre Watershed Partnership in a recent newsletter.
For Michelle Common, who lives on riverfront property in Ridgway at the headwaters of the Uncompahgre River, the discoloration comes with a toxic odor that burns the eyes and nose. She said her horses stopped drinking the water because of the “rancid” smell.
“I woke up the other night and said it smells like a dead animal floating down the river,” Common said, adding that she has had trouble selling her property because of the event.
“I’ve never seen this color before,” Common said. “Nobody is going to want to live off a sewer.”
Hydrowest Inc. owns Ouray Hydroelectric Power Plant. Owner Eric Jacobson said low pH iron from the blighted Idarado Mine in the Red Mountain Creek watershed near Ouray is what turns the water orange.
“We don’t dump anything in the river; it comes from mines above,” he said. “A red river is an acidic river, but the word ‘uncompahgre’ means ‘red water’ in Ute.”
Ouray city officials say they are considering a new procedure to notify community members of scheduled flushing activities.
“There’s a lot of sensitivity and attention to it because of what happened on the Animas side,” said City Administrator Patrick Rondinelli. “It’s something that has occurred for years, and there’s never been a big issue. All of a sudden, there’s a little bit more attention and sensitivity. So, let’s regroup on how we do this.”
An earlier version of this story included a photo caption that incorrectly identified Red Mountain Creek, which is a tributary of the Uncompahgre River.