The Livermore Valley is a vast landscape of foothills, canyons and pastureland in north Larimer County. It’s home to 100,000 acres of conserved land that provide habitat and a migration corridor for wildlife, including big-game animals. And the busy U.S. Highway 287.
“You could say that highway 287 was kind of a ribbon of death for wildlife, because they all have to cross it on their traditional east-west seasonal movements,” said Rick Knight, professor emeritus at Colorado State University, teaching wildlife and environmental conservation.
Standing in the Stonewall Creek bed, which runs underneath the highway, Knight explained why U.S. 287 was dangerous in this spot.
“There used to be a big old wicked, five strand barbed wire fence here,” he said.
Ranchers who owned pastures on either side of the highway would open this barbed wire fence in the creek bed only for their cattle to pass through. Otherwise, it was closed. Wildlife had to cross over on the highway above.
Stonewall Creek is part of a 30 mile stretch of U.S. 287 from Larimer County to the Wyoming border that can be treacherous for animals and motorists.
From 2017 to 2021, there were 309 vehicle crashes along this portion of the highway, according to a 2023 safety assessment study conducted by the Colorado Department of Transportation. The study found a 33% were caused by wildlife but this number may actually be higher because these types of crashes often go unreported.
While none of these were fatal for humans, over the past eight years, over 150 animals have been killed in collisions, said Jim Eussen, regional planning and environmental program manager with CDOT.
Knight, his wife Heather Knight, a conservationist, and a few others, came up with an idea to help big-game and smaller species safely cross the highway using Stonewall Creek and other natural underpasses fenced off by landowners.
“This is a typical wildlife friendly crossing. It’s beneath the highway,” Knight said, pointing to a large permeable wooden fence with three sections. “It has a gate so the landowners can still move their cows on either side of their pastures.”
Knight got permission from local ranchers to take down the barbed wire fence and put up this wildlife friendly crossing.
Situated under the highway, it’s a simple design. On one side of the gate are wooden posts that are far enough to allow deer, pronghorn, elk and other animals to pass through. But close enough to stop cows. On the other is a set of planks that allow creek water to pass through but not livestock.
“All they're doing is making motorists a lot safer, because wildlife have an alternative,” he said.
Wildlife fencing and overpass projects are happening across Colorado, funded by state and federal dollars. This includes the I-25 Greenland Wildlife Overpass in Douglas County, one of the largest overpasses in the world. These are big construction projects that can take many months to build. But crossings like the one in Stonewall Creek are much smaller. Each costs under $500 and takes a day to build.
“We tried it out with a volunteer day with students,” said Heather Dannahower, a Front Range Community College faculty member in the forestry, wildlife and natural resources program. “They loved it. We loved it. It seemed to be successful. And so it's just kind of grown from there.
Dannahower created the project with Knight, and they asked students from both of their higher education institutions to help out. Since 2021, a few hundred CSU and FRCC students have built four wildlife-friendly crossings under 287. They have partnered with the Colorado Department of Transportation for material support and received grants from Colorado Parks to help fund the project.
Each crossing starts with a conversation with the landowner to talk through the design and get the greenlight.
“When students get out there, we divide into little teams, so that everyone has a job, and everyone kind of knows who's in charge of their job,” she said.
The students have studied conservation concerns about the impacts roads and fences, as well as subdivisions and developments, can have on wildlife’s habitat, Dannahower said. But says hands on knowledge is necessary too.
“Getting them out on the landscape, to actually see the barriers, to actually be a part of a solution, rather than just reading about the problem. I think that's far more impactful,” she said.
Annie Hoffman agrees. She helped build the Stonewall Creek crossing in 2024 while attending FRCC. Her biggest takeaway from the project has been learning about wildlife movement, Hoffman said.
“It's been really, really fascinating to see how they learn, and how quickly they're able to kind of decipher what's safe for them and start using it regularly,” she said. “And, teach their offspring the following year how to do the same.”
The project is in a holding pattern right now while they look for more landowners to partner with and locations to install the crossings. In the meantime, students have torn down barbed wire fences or replaced the old wire with a more wildlife friendly fencing. They also monitor the wildlife and collect data from cameras installed at each location. It’s Hoffman’s job to manage the photos and videos the cameras take.
After her work on the wildlife friendly crossings, Hoffman was offered an internship at CDOT and now works there as an environmental resource and wildlife technician. So far, she’s catalogued close to a million photos of wildlife from the cameras.
“You can see how much use it's getting, and wildlife aren't getting hit because they're using a safer structure,” she said.
Last year, Colorado received $47 million in federal funding from the Bipartisan Infrastructure Law for safety improvements along 287 in Larimer and Boulder counties. CDOT will use some of that money for wildlife exclusionary fencing and other preventative measures.
The state agency is using the camera data from Stonewall Creek and the other wildlife crossings to help inform its strategies to prevent collisions between wildlife and drivers on Highway 287. As the photos and videos show, these animals are now finding a better way to cross the road.
