US 160 Wildlife Crossing

Challenge

La Plata County, Colorado, faced the state’s highest rate of wildlife-vehicle crashes. Along the 20-mile stretch of US Highway 160 between Durango and Bayfield, 58% of all accidents involved animals. This major migration corridor for mule deer, elk, and other wildlife was disrupted by the highway, which acted as a barrier between seasonal habitats, resulting in frequent collisions and rollover accidents. With over 9,000 vehicles traveling on this highway daily, a solution was critical to enhance safety for both humans and wildlife.

Solution

SEH partnered with the City of Durango and the Colorado Department of Transportation (CDOT) to complete construction management for a 37-foot-wide, 13-foot-tall wildlife underpass beneath US Highway 160, setting a new standard for safety and ecological connectivity. This precast concrete structure features a natural earth bottom, providing a safe, familiar terrain for wildlife to cross under the busy highway.

To guide animals toward the underpass and keep them off the roadway, crews installed 10,700 feet of wildlife fencing with eight escape ramps. Remarkably, animal tracks were observed in the underpass even during construction, affirming its effectiveness before completion, as noted by CDOT engineer Cory Kindle.

Constructed in phases to minimize traffic disruptions, the project maintained vehicle flow by detouring traffic while each half of the underpass was built. Once completed, the new roadway not only enhances safety for drivers and wildlife but also accommodates future highway expansion. This underpass is the first of 24 planned crossings along Highway 160, contributing to a broader effort to protect wildlife and reduce collisions.

Similar wildlife crossings along a 10-mile stretch of Colorado’s Highway 9 have achieved an 87% reduction in collisions, showcasing the transformative impact of these projects. By blending safety, functionality, and foresight, this project represents a significant step forward in sustainable infrastructure.