Colorado Wildlife Overpass Reduces Vehicle-Animal Collisions by 91%
New infrastructure project successfully connects 39,000 acres of habitat while enhancing road safety.
1Infrastructure Impact on Safety
A newly constructed wildlife overpass on Interstate 25 between Denver and Colorado Springs has achieved a 91% reduction in wildlife-vehicle collisions. Operational for ten months, the structure spans six lanes of traffic. This intervention addresses a previous average of one collision per day within this specific high-traffic interstate corridor.
2Design for Large Game
The bridge measures 200 feet wide and 209 feet long, featuring grass-covered surfaces and sloped entrances. These design choices accommodate large animals like elk and pronghorn, which often avoid narrow tunnels. Environmental managers noted that large game require open structures where they can maintain visibility for miles in every direction.
3Habitat Connectivity Success
The overpass successfully reconnects 39,000 acres of fragmented habitat on both sides of the interstate. Wildlife biologists have documented diverse species utilizing the crossing, including bears, coyotes, rabbits, and northern leopard frogs. Even the threatened Preble’s meadow jumping mouse has been tracked using the corridor, proving the structure's ecological versatility.
4Financial Efficiency and Budget
The project was initially supported by $22 million in federal funding and $8 million from state coffers. Remarkably, the Colorado Department of Transportation completed the construction for a total cost of $15 million. Officials emphasize that such infrastructure investments often pay for themselves by preventing expensive and dangerous vehicle accidents.
5Restoring Migration Patterns
For decades, pronghorn populations moving between Trinidad and Greenland were blocked by the I-25 barrier. Since the overpass opened, video footage confirms pronghorn are successfully reaching the west side for the first time in years. This restoration of natural movement patterns is a primary goal for state environmental management teams.
6National Infrastructure Trends
Colorado’s structure currently stands as the largest wildlife crossing in the United States. There are nearly 20 similar wildlife crossing projects currently underway across the country. These initiatives reflect a growing national strategy to protect wildlife habitats while simultaneously reducing human injuries and fatalities associated with frequent wildlife-vehicle traffic accidents.
7Operational Lessons Learned
State officials have learned that underpasses and tunnels are frequently ineffective for large game due to mobility restrictions and antler clearance issues. The success of this open-air bridge provides a scalable model for future projects. Consequently, the Colorado Department of Transportation is now actively planning additional wildlife crossings across the state.
8Long-term Ecological Significance
The project represents a shift toward integrating ecological connectivity into major transportation infrastructure. By prioritizing animal safety, the state has effectively mitigated a daily hazard for commuters. The documented 91% reduction in crashes serves as a critical benchmark for future infrastructure planning, proving that environmental design can yield immediate, measurable safety results.