Between heavy metal contamination from legacy mines in Silverton, high levels of E. coli from unknown sources, and higher water temperatures that stress aquatic life, the Animas River has its problems.
So, it was good fortune, historically, that the pristine waters of Hermosa Creek rushed into the Animas River north of Durango, providing an injection of clear, clean water that helped dilute some of the river’s water quality issues.
The 416 Fire that ripped through an estimated 54,000 acres last summer, mostly within the Hermosa Creek watershed on National Forest Service lands, has completely altered the landscape, and turned Hermosa Creek into another area of concern for the overall health of the Animas River.
In response, a partnership has formed between several researches groups to help not only understand how the 416 Fire has impacted Hermosa Creek and the Animas River, but also to track both waterways’ path to recovery.
“Fire is a natural component, and a necessary one, on the landscape, especially in the West,” said Scott Roberts, an aquatic biologist with Mountain Studies Institute. “Our forests need fire for regeneration, and our rivers are really resilient.”
Clean and clearHermosa Creek has long been revered for its impeccable water quality.
The mountains within the watershed have very low mineralization, and as a result, there’s never been any mining activity to imperil water quality, said Peter Butler with the Animas River Stakeholders Group.
And, the area is relatively devoid of any development, save for a portion of Purgatory Resort’s ski trail and some Forest Service roads. Even the grazing activity is light, and has no discernible impact.
“It was a largely undisturbed watershed,” Roberts said.
In a rare find, two populations of the native San Juan cutthroat trout were found in the Hermosa Creek watershed. Once thought to be extinct, only six known populations exist, said Jim White, an aquatic biologist for Colorado Parks and Wildlife.
In 2009, the state of Colorado awarded Hermosa Creek the “Outstanding Waters” designation, the first watershed in the state to receive such a designation that is not located in a wilderness area or National Park. In 2014, President Barack Obama passed the Hermosa Creek Watershed Protection legislation, protecting more than 100,000 acres.
Hermosa Creek’s benefit to the Animas has also been well-noted.
At Bakers Bridge, above the Animas River-Hermosa Creek confluence, some metals exceed aquatic life standards, Butler said. But below the confluence at Trimble Lane, all standards are met.
“The dilution from the high quality of water in Hermosa Creek certainly played a role in that,” Roberts said.
A changed landscapeThe 416 Fire broke out June 1, 2018, on the east side of the Hermosa Cliffs, and ripped its way into the Hermosa Creek watershed.
Heavy rains on the burn scar in July and September brought down catastrophic mudslides, damaging private property and causing nearly all the fish in the Animas through Durango to die. Sampling last summer and fall after the fire found water quality had been “substantially degraded,” Roberts said.
It’s a new normal for the two waterways. But communities and aquatic life alike, have to adapt.
Russ Howard, manager of the Animas-La Plata Operations and Maintenance Association, which manages Lake Nighthorse, said in a previous interview dam operators will wait to pump water out of the Animas River until runoff from Hermosa passes through.
Roberts said a partnership formed between MSI, the Colorado School of Mines and the USFS Rocky Mountain Research Station to highly monitor the waterways. The group placed monitoring devices at four locations (Bakers Bridge and Trimble on the Animas, Junction Creek and in Hermosa Creek), and plans to continue water sampling and study aquatic insects.
“Our purpose is to further examine the impacts, but also document the recovery,” Roberts said. “How long does it take for a river like the Animas or a creek like Hermosa to return to pre-fire conditions?”
Rivers do recoverAshley Rust, a post doctoral researcher with the Colorado School of Mines who is part of the 416 Fire monitoring partnership, cut her chops studying the impacts to water quality from the West Fork Complex Fire on Wolf Creek Pass in 2013.
There, she said the community held the same fears and anxieties.
The big issue, Rust said, was when monsoons would pummel steep hillsides burned in the fire, which would send torrents of sediment into the river, killing aquatic life.
But after a few years, vegetation returned and hillsides started to stabilize. Fish and aquatic insects, too, learned to adapt and even thrive.
“You’re basically watching a brand new river form,” Rust said. “It’s a reset, which generally helps aquatic life in the long-term. Our story was a story of hope. In one to three years, we saw a remarkable recovery.”
MSI’s Roberts said research from other areas with fires show waterways recovery within one to 10 years, with three to five being the average. Because only 3% of the 416 Fire burned at a “high-severity” level, he expects recovery to be on the short end.
Back to lifeIndeed, plans are already in the works for the recovery of the Animas River and Hermosa Creek.
In a sort of emergency response action after the fire, CPW trekked up to the two locations where the native San Juan cutthroat trout were found, and brought them back to Durango. The fish are being kept in isolation at the hatchery, and the plan is to release them back into the wild this fall.
White said CPW will also conduct another fish survey on the Animas in the fall, after spring runoff and the monsoons in the summer, and hopefully in Hermosa Creek, to assess the damage from the 416 Fire.
If everything goes according to plan, CPW also intends to reintroduce a good amount of fish back into the Animas River.
“I think they’ll do well,” he said. “But I’m more optimistic than most.”