A few roads go a long way
Agency partnerships address post-fire flooding in burn scars
It’s hard to imagine a world without roads. Even at the foot of the Rocky Mountains on the Colorado Front Range, a closed road only results in a quick reroute and a slightly extended commute. There’s always another road, another option – plus-2-minute, plus-3-minute, and gas-saver alternate routes. A backup reroute is seconds away if you miss your turn with another reroute waiting if you miss that turn. But on the other side of the Continental Divide a few roads go a long way, and their structural integrity turns the economic gears for the surrounding communities.
Stillwater Road, a major throughfare in Arapaho National Forest that links two highways across the base of the Continental Divide in Grand County, Colorado, is one such road. Stillwater provides access to the Grand Lake community and cuts through one of the most popular elk hunting locations in Colorado, making it a critical forest access route for outfitters and hunting guides and a resource local communities rely on. It also lies in the middle of Colorado’s second largest burn scar. When heavy spring flooding blew out a culvert and completely washed away a 30-foot section of the road creating a 15-foot-deep ravine, the surrounding communities lost an economic lynchpin in a matter of seconds.

“This site had been a concern since the East Troublesome Fire when the original 5-foot pipe started getting plugged and causing drainage issues,” said Kamber Box, forest engineer. “As the Forest Service and Northern Water were working on a new design to accommodate the unstable sediment, heavy rain in the burn scar led to the big washout. It’s a problem you can see across the forest.”

“In a healthy state, soil is essentially a sponge with a protective cover of forest litter,” said Tracy Weddle, forest hydrologist for the Arapaho and Roosevelt National Forests & Pawnee National Grassland. “But a severe fire often consumes the protective litter and canopy, burns fine roots, and collapses the topsoil sponge. When conditions become extensive across the landscape, hillslopes lose their ability to absorb rainfall which leads to erosion and concentrated flooding in stream channels.”
Conditions became extensive after 2020.
Upstream of the Stillwater Creek crossing, 74% of the watershed burned at moderate soil burn severity and 2% at high soil burn severity during the East Troublesome Fire.
“This hugely increased muddy runoff that plugged the culvert, causing it to fail along with the road prism,” said Weddle.
The East Troublesome Fire is Colorado’s second largest wildfire behind the Cameron Peak Fire occurring the same year. The watershed impacts were far reaching. Northern Water, a water provider to over 1 million residents in northeastern Colorado, had over 50% of their water supply impacted by these fires, including water that makes its way to residents on the front range.
“That’s why partnerships are so important to wildfire recovery work,” said Eric Freels, district ranger, Sulphur Ranger District, Arapaho National Forest.
The Forest Service has a longstanding agreement with Grand County for maintenance of Stillwater Road in addition to partnering with Northern Water to address watershed stabilization and sediment reduction in areas affected by wildfire. Rebuilding Stillwater Road is one of many post-fire projects funded under this disaster recovery partnership.
“Northern Water and Grand County have great relationships with hardworking local contractors who spent five months implementing our collaborative designs to reroute Stillwater Creek, install an improved 19.5-foot arched pipe and 5-foot overflow pipe, rebuild Stillwater Road, and stabilize the soil to better handle flooding in the burn scar,” said Freels. “The new design is a major improvement and the increased work capacity from our partners made it a reality.”


In addition to its increased size and improved overflow features, the new stream crossing consists of several natural features. Part of the design process included modeling what the original streambed looked like as far as pools and ripples for the fish. The result is that the arched pipe extends four feet into the streambed and is lined with streambed simulation material designed specifically to mimic those natural characteristics and allow for aquatic organism passage, like fish. Willows were also planted along the edge of the stream to improve stabilization as they grow.

Crews completed the work with hydroseeding and seed mats to help with revegetation, but Forest Service officials say it could take a couple of years for vegetation to reestablish, that’s why it’s important for people to not enter that area and to stay off the hydroseeding in the meantime. The Forest Service is planning for additional planting and stabilization work in this area in the upcoming years.


“This was the first road repair project at this scale under our partnership and it’s already helping expedite future projects with the lessons learned,” said Freels. “There’s more work to do on Stillwater. There are spots where we have debris crossing the road and another stream crossing that’s vulnerable with inlets that are beginning to clog. The Forest Service and Northern Water are going to be working together on continued efforts to stabilize these watersheds and reduce sediment, to include some other instream work as well as addressing other stream crossings.”
