I-25 South Gap Project Mitigation Design and Post-Construction Research

ECO-resolutions provided specialized wildlife mitigation expertise for the I-25 South Gap Project, a major interstate widening project between Denver and Colorado Springs along Colorado’s Front Range. This north-south highway effectively separates the foothills landscape to the west from the plains to the east, creating a barrier to wildlife movement and resulting in wildlife-vehicle collisions. Prior to construction, these types of collisions were one of the most common crash types in the corridor, with direct impacts to motorists and wildlife and contributing to substantial travel delays.

The team identified and evaluated potential wildlife crossing structure locations in the context of other project needs. ECO-resolutions provided specialized expertise to the design team to ensure that the wildlife crossings meet the movement needs of large and small fauna in providing safe passages beneath six traffic lanes. Given the complexities of a transportation project of this magnitude, close collaboration between engineers and biologists ensured that small adjustments to the project would not impact the effectiveness of the wildlife mitigation. ECO-resolutions remained engaged throughout design and construction to ensure the long-term functionality of these mitigation investments. Construction of five large (100’ wide) bridge underpasses and associated wildlife exclusion fencing, escape ramps, and wildlife guards was completed in 2021.

Monitoring efforts began in 2021, with ECO-resolutions leading a team of researchers from WEST, Rocky Mountain Wild, and Pinyon to evaluate the effectiveness of these mitigation investments.