Home
Explore, enjoy and protect the planet

WSDOT Proposes Wildlife Bridges for I-90

On June 20th, the Washington Dept. of Transportation (WSDOT) announced its preferred alternative for the I-90 Snoqualmie Pass East project that would include the wildlife bridges recommended by biologists. If approved after the Final EIS next year, this would provide a high level of connectivity for many wildlife species, making it one of the best highway crossing facilities for wildlife in the country. The design includes a dozen higher and longer highway bridges and numerous large culverts, where animals can cross under the freeway. In addition, at two locations, overpasses exclusively for wildlife will be built. The design also provides for stream and wetland restoration.

Unprecedented Support from Environmental Groups

At the press conference, Charlie Raines, Director of the I-90 Wildlife Bridges Coalition, gave the group’s endorsement to the project. The support of groups such as Sierra Club, Conservation Northwest, Alpine Lakes Protection Society, and Kittitas Audubon for such a project is unprecedented. The Coalition based its support on meeting the objective of a high level of wildlife connectivity. This is the result of WSDOT including wildlife connectivity as a goal of the project, plus the strong push for connectivity from the Forest Service and U.S. Fish and Wildlife Service. Public support for the project (with the wildlife bridges) was evident at public hearings, in no small part due to the work of environmental groups. With this unique collaboration, WSDOT set the stage for finding a mutually agreeable solution.

This is quite different from the usual opposition to these types of projects, which often end up being resolved in court – as was done on the upgrade of I-90 just west of Snoqualmie Pass. This new approach resulted in a better design that will be built sooner – thus saving money.

Safe Passage for Animals and Drivers

This project will substantially improve both driver safety and wildlife protection where the highway cuts through a major wildlife corridor in the heart of the Cascades. These bridges, together with fencing and retaining walls, will reduce vehicle collisions with larger animals that can be expensive or even fatal, as well as accidents caused by drivers swerving to avoid small animals. 

Bridges Complement Investment in Habitat

WSDOT's decision to build high quality wildlife passage into the I-90 reconstruction goes hand in hand with land acquisition in restoring Cascades wildlife corridors. Through a variety of efforts over the past decade, including land exchanges, and campaigns by The Cascades Conservation Partnership and the Mountains to Sound Greenway, more than 150,000 acres of habitat in the central Cascades have been acquired and protected. Over 10,000 acres of habitat have been acquired within just two miles of this project. Now, I-90 remains the largest barrier to wildlife.

These wildlife bridges are a good investment, for a project that will last 50 years. These connections are critical to keeping species’ populations healthy by providing pathways for feeding, breeding, juvenile dispersal, migration and adapting to habitat changes. This will allow more flexibility in managing the public and private forest lands in the Cascades, and provide a margin of safety for future listings of endangered species. Among the 70 terrestrial and aquatic species that will benefit from the wildlife crossings are elk, deer, cougar, bear, wolverine, pine marten, fox, numerous amphibians and reptiles, and fish such as Kokanee salmon and endangered bull trout.

Challenges Ahead

Two significant issues remain. We requested improved crossing structures at the Kachess River and WSDOT has agreed to re-look at that easternmost location when final design of that segment is begun in a few years. Also, the mitigation for impacts to forests and wetlands from the freeway expansion is yet to be developed, and we will work with WSDOT to insure adequate high quality mitigation is provided. The Legislature approved $388 million for the initial five-mile stretch, which would include major wildlife crossing structures at Gold Creek (near Hyak). It would also add bridges to avoid avalanches along Keechelus Lake. Construction could begin in early 2010. However, most of the proposed wildlife structures, including the rock knob overpass near Keechelus Dam, are in later phases that are not yet funded.

Contact: Washington DOT: www.wsdot.wa.gov/projects/i90/snoqualmiepasseast

Contact: I-90 Wildlife Bridges Coalition: www.i90wildlifebridges.org