While 100,000 drivers barrel down Interstate 25 in Colorado each day, moose, mountain lions, elk, deer, bears and pronghorn are happily hoofing right over their heads.
The Greenland Wildlife Overpass, a lush, landscaped bridge spanning the six-lane highway between Castle Rock and Monument, has given Colorado’s wildest residents their own 200-by-209-foot overpass while connecting 39,000 acres of habitat that the interstate had long divided, according to the Colorado DOT.
The overpass, which opened in December and is the largest in North America, was built for good reason: that same stretch of I-25 averaged one wildlife-vehicle collision every single day — some deadly.
Mary Rodriquez, 43, lost her father, Victor, when a passing car hit a 700-pound elk, launching it into the air and through his windshield.
“He was killed immediately,” Mary told CBS News Colorado. “We are trying desperately to cope with losing him.”
In 2021, Congress passed the bipartisan infrastructure law, which established the Wildlife Crossing Program after identifying that there were more than 1 million wildlife-vehicle collisions annually across the US.
“The I-25 Greenland overpass is a momentous feat,” said Colorado Gov. Jared Polis. “Colorado is leading the way in reducing wildlife-vehicle collisions, and protecting critical habitat for generations to come.”
The project received $22 million from the feds and another $8 million from the state, but was completed for about $15 million and finished in just one year.
“We’re using the remaining money figuring out how to reinvest that money into the corridor, and one of the needs we have is building wildlife fencing along the highway,” Colorado DOT Environmental Manager Chuck Attardo told CBS Colorado.
The overpass is the capstone of the $419 million I-25 South Gap project — an 18-mile corridor upgrade that added four new wildlife crossings and 28 miles of deer fencing, projected to cut animal-vehicle collisions by 90%. And the overpass fills the final 3.7-mile gap in that system along one of Colorado’s busiest stretches of highway, CDOT said.
While the overpass was first designed for elk and pronghorn, smaller species are using it as well, the department said.
California is in the process of building the Wallis Annenberg Wildlife Crossing, a controversial project that’s run into major money problems and run-ins.
A $23 million land bridge in Texas near San Antonio has also been an overwhelming success — and at least 19 states are now busily in the process of building wildlife crossings.
In New York, conservationists are prioritizing the Adirondack Northway I-78 for new crossing structures due to high collision rates. The Nature Conservancy and NYDOT installed a “critter shelf” inside a Route 12 culvert near Boonville, allowing species like bobcats to pass safely.
A third New York project took place in 2024 when Jefferson County’s Wellesley Island State Park opened a new wildlife crossing culvert.
“It’s keeps the motorists safe, and it keeps the animals safe,” said Rodriguez. “it’s a win-win for everyone.”
