Washington Wildlife Bridge Hits 10,000 Crossings, Zero Deaths

A wildlife bridge over one of Washington's busiest highways just proved that a simple idea can save thousands of lives.

The Washington State Department of Transportation announced this month that animals have crossed the I-90 Snoqualmie Pass overpass 10,000 times since it opened. Not a single animal has been hit by a car in that stretch of highway during those crossings.

The bridge sits at Snoqualmie Pass, where Interstate 90 cuts through critical wildlife habitat in the Cascade Mountains. Trail cameras have captured everything from deer and elk to smaller mammals using the vegetated overpass to safely reach the other side.

The numbers get even better when you count the 11 underpasses in the same area. Together, these crossings have recorded nearly 40,000 safe animal passages since 2014.

Before these structures existed, the story looked very different. Between 2019 and 2023, transportation crews removed more than 39,000 animal carcasses from Washington state highways. In the Snoqualmie Pass area where the crossings now stand, that number has dropped to nearly zero.

Conservation Northwest helped advocate for and implement the overpass. The organization says the structure has reconnected habitat between the North and South Cascades, allowing animal populations to thrive instead of becoming isolated and genetically weaker over time.

The Ripple Effect

The success at Snoqualmie Pass is creating waves far beyond Washington. Transportation officials and conservationists across the country now point to this project as proof that highways and healthy ecosystems can coexist.

The economic impact tells an equally compelling story. Each deer collision costs about $15,000 in vehicle damage, medical bills, and other expenses. For elk, that number jumps to $54,000. Wildlife crossings can reduce these collisions by up to 97%, saving states hundreds of thousands of dollars every year while preventing human injuries and deaths.

Washington officials are so convinced by the results that they've committed to building 16 more crossings along Snoqualmie Pass by 2031. The expansion will create a connected corridor spanning from the Cascade Mountains to the Olympic Peninsula.

The project is also inspiring other states to invest in similar infrastructure. Research from Pew Charitable Trusts shows that each dollar spent on wildlife crossings returns value through prevented collisions, with some crossings reducing crashes by 90%.

"Our mission is keeping travelers connected to wherever they need to go, no matter if it's by wheel, foot, paw, or hoof," WSDOT shared in announcing the milestone. That vision is becoming reality one crossing at a time.