North America’s largest wildlife overpass is delivering a substantial improvement in road safety near Larkspur, Colorado. Opened in December above six lanes of Interstate 25, the bridge forms part of a network that has reduced wildlife–vehicle collisions by 91% over its first ten months. The result slightly exceeds the 90% reduction anticipated by Colorado transport officials. Measuring 200 feet wide and 209 feet long, the structure provides approximately 3,900 square metres of crossing space.
The project combines the overpass with five underpass tunnels, offering alternative routes for smaller animals and those less inclined to cross the bridge. Extensive fencing channels wildlife towards these passages. Bears, elk and moose benefit from the network, as do smaller creatures such as rabbits and northern leopard frogs. Bridget O’Rourke, a spokesperson for Colorado Parks and Wildlife, welcomed the results and highlighted the effectiveness of crossings combined with guiding fences.
The benefits extend to motorists on the Larkspur–Monument corridor, where wildlife collisions previously averaged one a day. Traffic delays have declined by 9%, with fewer collisions requiring safety personnel to close lanes. Colorado is now assessing six additional locations for wildlife overpasses, including its first designed specifically for Rocky Mountain bighorn sheep. Sites under consideration include westbound Interstate 70 at East Vail Pass, between Vail and Copper Mountain; Interstate 25 near the New Mexico border; and US 160 east of Cortez. Other proposed locations are west of Craig and near US 287 south of the Wyoming border.
