Flagstaff, AZ – Drivers heading along Interstate 17 near Willard Springs may have noticed an unusual new structure rising over the lanes: Arizona’s first major wildlife overpass.
According to the Arizona Department of Transportation (ADOT), crews have installed 26 bridge girders for the I-17 Willard Springs Wildlife Overpass, located just south of Flagstaff. The project also includes specialized wildlife fencing to help guide animals safely across. When finished in fall 2026, officials say it will allow elk, deer, and other animals to cross the busy freeway without danger to themselves or motorists.
Wildlife overpasses first gained popularity in Europe, particularly in the Netherlands, where dozens of “ecoducts” have been constructed since the 1980s. These bridges are landscaped with soil, plants, and fencing so animals perceive them as natural corridors. Studies from Europe and Canada show they reduce animal-vehicle collisions by as much as 80 to 90 percent while helping preserve migration routes for species that need large ranges to survive.
ADOT says the I-17 crossing is designed with those same principles. The structure will blend into the surrounding forest, allowing elk and other wildlife to follow their natural movement patterns. The benefits are expected to be twofold: protecting wildlife populations and reducing serious collisions, which can cause significant vehicle damage and injuries.
For now, the freeway is down to one lane in each direction at the construction site. ADOT notes that no full closures are planned during the project.
