Eleven months after the Black Hollow flood, Colorado Parks and Wildlife went to sample trout downstream of the debris flow, from stations one to 16 miles away. They couldn’t find a single one.
This suggests “a complete loss of the fishery within that reach,” CPW Aquatic Biologist Kyle Battige said. In other words, all the fish in the Poudre River as far as 16 miles from the July 2021 disaster had been killed.
The deadly effects of the flood and mudslides, which also killed four people and destroyed six homes, were exacerbated by burn scars from the Cameron Peak fire in 2020, the largest fire in Colorado history at over 208,000 acres.
Cameron Peak, along with the East Troublesome and Williams Fork fires, burned through the Arapaho and Roosevelt National Forests. It killed trees whose roots kept the soil in place, so that any major rainstorm would wash heavy sediment into the river, making it uninhabitable for trout.
The Forest Service hopes to restore fish habitats affected by the 2020 fires through a new $10 million, eight-year agreement with nonprofit Trout Unlimited.
Over the past three years, the Forest Service has made multiple partnerships for recovery from the 2020 fires. This is the first to focus on aquatic species and watershed health. About half the funding will go to restoring stream health and the other half to rebuilding Forest Service infrastructure, making it more fish-friendly where possible.
Since the fires, the streams have run faster, warmer and dirtier: all unfavorable for a healthy fish population. Before, roots held soil on the riverbanks in place and absorbed some of the runoff from streams, slowing the water’s flow. Now, the water carries more debris and moves faster, which raises its temperature. Burn scars and erosion created steeper riverbanks that worsened the issue.
The unhealthy riparian ecosystem doesn’t just affect fish.
This landscape, where the stream is disconnected from the land around it called the floodplain, prevents that land from absorbing excess water during flooding, increasing the likelihood of flash floods and mudslides. The Black Hollow flood and another deadly flood in Larimer County in 2022 occurred in areas burned by the Cameron Peak fire.
Colorado 125 in Grand County, one of four roads in and out of the county, continues to sustain damage from mudslides and debris flow from the East Troublesome burn scar, necessitating regular closures, Grand County spokesperson Christine Travis said.
Northern Water, which provides water to millions of people along the Front Range, has had to install debris catching systems and rely on other reservoirs due to sediment in their Willow Creek Reservoir, Northern Water spokesperson Jeff Stahla said.
“Now more than ever, we are recognizing that forest health and stream health are part of the general picture of ecosystem health that provides benefits, certainly in the ecosystem, but also results in higher-quality drinking water,” Stahla said.
Trout Unlimited will focus on process-based restoration, said Quinn Harper, the group’s Upper Colorado River Project manager. Rather than trying to bring back the exact pre-fire landscape, they aim to “reconnect ecosystems” and allow natural processes to build up an environment that is healthy, but different from before.
This will include replanting willows and other trees and building structures in the water that slow its flow and allow for sediment deposition.
“It’s going to be a healthier ecosystem that is more in line with current conditions on the ground,” Harper said.
Healthy riparian ecosystems are also more fire-resilient in the long-term, Harper said. Vegetation and connected floodplains keep the area moist, slowing down any future fires that come through.
“The ideal outcome is that we are creating more resilient watersheds that are better able to deal with a post-fire environment where they are, and also future fires,” Forest Service spokesperson Reid Armstrong said. “And we restore great habitat where there’s potential for not just greenback cutthroat trout, but also all other kinds of aquatic and riparian species.”
The Forest Service has worked with Trout Unlimited on multiple greenback cutthroat trout restoration projects. Currently, they are working together on the Poudre Headwaters Project to restore threatened native trout populations in that area.
The funding for the new agreement comes from a $72 million supplemental disaster appropriation from Congress to the Forest Service in fiscal year 2022. Organizations including Northern Water began pushing for this funding soon after the 2020 fires.
“We’re very grateful that between the federal government and the state government, they’ve seen the urgency for this work, but we’re scratching the surface in terms of the overall large amount of acreage that was damaged, and we know that some of them will likely never get addressed,” Stahla said. “They’re recognizing that some things we can be doing in advance will make us more resilient.”
Now, the Forest Service and Trout Unlimited are in the process of choosing priority areas for the recovery work: areas with the most stream degradation, continuing flash flooding and sedimentation issues. Over the next months, they will discuss priorities for the project in the upcoming year, Harper said. Work is expected to begin in summer of 2024.
Though the agreement lasts eight years, the Forest Service doesn’t expect their work with Trout Unlimited to end after that, Armstrong said.
“It’s really important to think about how difficult it is to recover after a fire and how long it takes and how sometimes it’s not as successful as you’d like it to be,” Big Thompson Watershed Coalition spokesperson Will Davis said. “Instead of thinking about how we recover from fire, we need to be thinking about how we can prevent these catastrophic fires from happening. Because that money is so much better spent, and our lands and communities are better served by doing it before the fire.”