North America’s largest wildlife overpass is saving animal lives

Officials report a 91% drop in collisions since the crossing opened in December.

October 21, 2026

The I-25 Greenland overpass is touted as the largest wildlife crossing in North America. (Courtesy of Colorado Governor’s Office)

The I-25 Greenland wildlife overpass near Larkspur has cut collisions between cars and animals by 91% since it opened in December 2025,, according to a recent report.

The Colorado Sun reported that state wildlife managers and transportation officials documented that the number of collisions occurring along Interstate 25 between Larkspur and Monument has dropped from about one per day to just two total in the roughly 10 months since the crossing opened.

Considered the largest wildlife crossing in North America, the land bridge spans six lanes of interstate traffic, connecting 39,000 acres of habitat on both sides of the highway.

The $15 million overpass was strategically located to address a 3.7-mile gap in wildlife crossings, completing a wildlife crossing system of underpasses and fencing that was part of the I-25 South Gap project.

While the overpass has been used regularly by animals such as elk, deer, and pronghorn that pose a risk to themselves and drivers when they cross the highway, wildlife officials have been pleasantly surprised to see smaller animals such as rabbits and northern leopard frogs also using the crossing, The Sun reported.

The results beat what Colorado Department of Transportation officials had originally predicted a 90% drop in collisions.

“Colorado is leading the way in reducing wildlife-vehicle collisions, and improving safety for both our motorists and wildlife,” said Gov. Jared Polis following the crossing’s completion in December. “The I-25 Greenland wildlife overpass is a momentous feat, in our continued work to expand safe transportation options for both humans and wildlife, protecting critical habitat, and our amazing outdoor spaces for generations to come.”

Six more crossing systems are under development across Colorado, The Sun reported.

The Colorado Wildlife and Transportation Alliance maintains an interactive map that shows all the completed wildlife crossings in the state with info about each project.