Since opening in December, North America’s largest wildlife overpass spanning six lanes of Interstate 25 near Larkspur, Colorado, has resulted in a dramatic 91% reduction in collisions between vehicles and animals, benefiting both wildlife and motorists alike.
- 91% drop in animal-vehicle collisions since overpass opened
- Structure includes the largest wildlife bridge and underpasses
- Plans underway to build six more wildlife crossings in Colorado
What happened
In December, Colorado unveiled the largest wildlife overpass in North America over Interstate 25 near Larkspur, designed to provide safe passage for bears, elk, moose, pronghorn, and smaller animals. This 200-foot-wide, 209-foot-long overpass along with five underpass tunnels funnels animals across a busy highway, greatly reducing dangerous interactions between wildlife and vehicles.
Ten months after its opening, data has confirmed a 91% reduction in collisions on this route, surpassing initial expectations of a 90% decrease. Daily collisions that once averaged about one per day have now dropped significantly, along with a 9% decrease in traffic delays caused by accident-related lane closures.
Why it feels good
The success of this overpass brings relief to both wildlife conservationists and drivers. Animals like migratory pronghorn, which struggled to cross the highway for decades, are now safely navigating the crossing, with the first recorded pronghorn crossing in 30 years recently captured on video. This improvement not only helps maintain animal populations and their natural movement but also reduces the risk of traumatic and costly accidents for people.
The design includes not only large mammals but also smaller and more timid species such as rabbits and northern leopard frogs, ensuring broad ecological benefits. Officials are thrilled with the proven model, which highlights how thoughtful infrastructure can harmonize human transportation needs with wildlife preservation.
What to enjoy or watch next
Inspired by the Larkspur overpass's success, Colorado is scouting six more locations for similar wildlife crossings across key routes including I-70 near Vail Pass, I-25 near New Mexico’s border, and other highways near Craig and south of Wyoming. These projects promise to further enhance road safety and wildlife connectivity across the region.
One exciting upcoming project will cater specifically to the Rocky Mountain bighorn sheep, a species needing tailored crossing solutions. As more overpasses and underpasses come online, drivers and nature enthusiasts alike can look forward to safer, smoother journeys that respect and protect Colorado’s diverse wildlife.