BRECKENRIDGE — Millions of gallons of rust-colored water poured from a mine addit Monday morning in Breckenridge, coloring parts of the Blue River bright orange.

Town officials said there was no immediate known health threat from the surge of orange water, and no threat to the town’s water supply, which comes from Goose Pasture Tarn well upstream of the contamination.

The source of the tainted water was pinpointed at the Iron Spring mill site along Boreas Pass Road, just past the town’s ice rink, which then caused the Blue to run orange from areas near the Maggie Pond down to the confluence of the Blue and French Gulch.

It’s not unusual for water to seep from abandoned mines, especially during spring runoff, but the unusually high flow of water coming from the site was of concern to local officials, who took water samples and looked downstream for dead fish.

A prodigious snowfall this winter may have caused the sudden flow. Snow and ice may have dammed the mine addit, and if that gave way Monday morning, it would have allowed the massive surge of water to flow downstream all at once. Snow banks along the stream were colored orange to a height of about two feet, indicating a sudden surge.

Local residents like Jim O’Hea, a 20-year local, said they’ve never seen the Blue River discolored to that extent.

“I’m on a mission. I’m going upstream to try and find where it’s coming from,” O’Hea said after eyeing the water from a bridge near the Riverwalk Center.

Water quality expert Brian Lorch, a resource specialist with Summit County’s open space department, said it’s hard to know whether there are any immediate water quality concerns without sampling the water to check for the presence and levels of any potential contaminants.

Abandoned mines are often associated with acid mine drainage, which can include dissolved metals like zinc, cadmium, arsenic and lead. Some of the metals can be toxic to trout at certain concentrations.

Lorch, who has worked on abandoned mine remediation projects with the county, said there’s nothing that can be done to mitigate or contain the spill at this point.

The only way to prevent such an accident is by cleaning up abandoned mines pro-actively, he said.

The county and the town of Breckenridge are jointly working on such a remediation project in French Gulch, where a treatment facility to clean water from the abandoned Wellington-Oro Mine is slated to be built this summer.

Andy Carlberg, director of the Breckenridge Sanitation District, took water samples from near the addit Monday morning, and said he would follow the plume downstream, taking additional samples. He said there was no immediate concern about operation of the district’s water treatment facility. The samples will be sent to Denver for testing, he said.

“It’s more of a concern for the aquatic environment,” he said.

Tom Kroening, of the Colorado Division of Wildlife, said his agency typically wouldn’t be involved unless fish start to die in the stream.

“I’m not happy to see it, but it looks like it’s not getting past French Gulch,” Kroening said. The Blue River downstream of the confluence is of more concern to the wildlife agency from a fisheries standpoint.

Bob Berwyn can be reached at (970) 331-5996, or at bberwyn@summitdaily.com.

On alert

Residents should be on the lookout for dead fish during the next few days, and report them to the Colorado Division of Wildlife at (970) 468-5848 as soon as possible. The most likely area for them to end up is near the Breckenridge Recreation Center, just before the Blue River flows underground for a short stretch.