I-90 Wildlife Bridge

As you pass under this wildlife bridge, a good chance exists that elk, deer, coyotes, and/or numerous other large and small wildlife species are crossing just overhead.  Watch for North America’s largest wildlife overcrossing bridge while driving along Interstate 90, between mileposts 61 and 62, about nine miles east of Snoqualmie Pass.

For decades Interstate 90 has served as a critical east-west travel corridor accommodating tens of thousands of motor vehicles daily.  Unfortunately, the highway has prevented numerous wildlife species from safely traversing their natural north-south migration corridor in the Cascade Mountains. Wildlife-vehicle accidents regularly killed magnificent animals, frequently left vehicles totaled, and sometimes resulted in human injury and death.

As part of a larger project to renovate and widen a 15-mile stretch of I-90, the Washington State Department of Highways (WSDOT), the US Forest Service, and numerous non-profit organizations partnered to design and build this overpass and several natural underpasses to allow wildlife to reconnect with their entire natural range.  Fences along the highway channel wildlife to the safe crossings. Mountains to Sound Greenway Trust staff planted native vegetation atop the bridge, completed in 2019.

WSDOT has documented the project’s success in a short video of wildlife crossing the bridge and underpasses.  The award-winning documentary Cascades Crossroads beautifully recounts the history of the project and the contributions of numerous partnering organizations.  Of course, PLEASE do not watch either video while driving!

Photo Credits:

Wildlife bridge from highway – Merrill Images

Vegetation planting on bridge top - Mountains to Sound Greenway Trust

All other photos – Washington State Department of Transportation