State, local and federal agencies are working to figure out what is causing changes to the waters and streambed of Lincoln Creek.
In recent days, the water in Lincoln Creek below Grizzly Reservoir has turned a milky green color and a sediment — yellow in some places, white in others — has settled on the streambed. The water flowing into the reservoir from upper Lincoln Creek ran yellow on Saturday.
According to Andrew Wille, a concerned citizen and educator who has done a field study in the area, the discolored stream is not totally unusual.
“I would say (Lincoln Creek above the reservoir) is always like that, but it might be a little worse this year,” said Wille, who is also a member of Pitkin County’s Healthy Rivers board but clarified he was not speaking on the group’s behalf.
What is unusual, Wille said, is that the issue extends below the reservoir to the water flowing down Lincoln Creek to its confluence with the Roaring Fork River.
“I was just kind of concerned and upset it made its way into the Roaring Fork,” he said.
A culprit could be defunct mines in the area, where prospectors mined gold, silver, lead and copper in the early 1900s. It includes the well-known Ruby Mine near the ghost town of the same name.
Bryan Daugherty, an environmental health specialist with Pitkin County, took samples of the water in the creek last week.
“It could be that we have had significant weather up there and it has opened up some of the channels or something that expose more of the mining waste,” Daugherty said. “We just don’t have a great answer as to why it looks different than it has in the past years.”
Officials may have more answers after Tuesday, when a team of water quality experts from different agencies, including the U.S. Environmental Protection Agency, the Roaring Fork Conservancy and others, are scheduled to test the waters of Lincoln Creek. It is part of an ongoing water quality monitoring program.
Mines could be a cause
Jeff Graves, program director for the Colorado Inactive Mine Reclamation Program, said the Ruby Mine was brought to his attention last year when there was a fish die-off in Grizzly Reservoir. His agency, the Colorado Division of Reclamation, Mining and Safety, joined other agencies in water quality sampling in early summer. Those results are not back yet.
But Graves said the problem may not be caused solely by the Ruby Mine.
“There’s obviously some legacy mining up there; that includes the Ruby Mine,” he said. “But there’s also a significant geologic component unrelated to mining. So there are a couple different things going on that we need that sampling data back to clarify what the actual cause of any potential problems are downstream.”
Graves estimated there are about 400 mines across Colorado that are discharging into waterways and potentially creating a water quality issue downstream. He said there has not been any reclamation done on the Ruby Mine and that it would not have fallen under any regulatory authority at the time it was mined around the turn of the 20th century.
Much of the water collected in Grizzly Reservoir from the high mountain drainage of Lincoln Creek is sent through the Twin Lakes Tunnel under the Continental Divide to be used in Front Range cities. Colorado Springs Utilities owns the majority of the water from the Twin Lakes system, which represents the city’s largest source of West Slope water and about 21% of its total supply.
Twin Lakes Reservoir and Canal Company Manager Bruce Hughes said on Monday that the Twin Lakes system was operating normally, which at this time of year means not diverting to the Front Range and instead letting the water from Grizzly Reservoir flow down Lincoln Creek.
Graves said in general, the environmental concerns associated with mines involve aquatic life like fish and the bugs they eat. The orange color of the water and stained streambed is from iron; the white is from aluminum, he said.
“Generally speaking, there is very little human health concerns associated with the sites,” he said. “Most of the time, it is aquatic life concerns and the specific concern is zinc. Fish are very intolerant to high levels of dissolved zinc in the water.”
As of Saturday, there were still plenty of fish swimming in Grizzly Reservoir.
Aspen Journalism covers rivers and water in collaboration with The Aspen Times. This story ran in the Sept. 27 edition of The Aspen Times.