Road Ecology Center

Interstate 90 over the Cascades is significant barrier to over 250 species of wildlife, including cougar, elk, deer, mustelids (otters, fishers, badgers, etc.), amphibians and reptiles. In the vicinity of Snoqualmie Pass, urban development to the west and agriculture and resort development on the east has shrunk the forest connecting north and south Cascades to less than 64.6 kilometers wide.

The Washington State Department of Transportation (WSDOT) is proposing to expand a 24.15-kilometer stretch of Interstate 90 just east of Snoqualmie Pass through a particularly critical zone for north-south wildlife corridors. These corridors have been identified through numerous studies, and the state has made ecological connectivity a project goal, along with increasing capacity, straightening curves, and repaving. A preferred alternative design for this project was chosen in summer 2006 that includes numerous high quality crossing structures, and was endorsed by the I-90 Wildlife Bridges Coalition.

The I-90 Wildlife Bridges Coalition is made up of over 40 local and national conservation organizations and has been working with WSDOT, other public officials, transportation interests, and the public to promote high quality wildlife crossing structures in this project while educating the public in our state about transportation and ecology issues. An additional role beyond advocacy and education that the coalition has engaged in during 2006 is citizen wildlife monitoring at the proposed crossing structure locations.

Good data is available to inform where to build crossing structures. WSDOT and the US Forest Service collaborated on a study entitled I-90 Snoqualmie Pass Wildlife Habitat Linkage Assessment (Singleton and Lehmkuhl, 2000) that used tracking and and road-kill counts to map existing crossing activity. Additional relevant information comes from analysis leading to the Snoqualmie Pass Adaptive Management Area Plan and I-90 Land Exchange (US Forest Service, 1997 and 1999) and Washington State Dept. of Fish and Wildlife studies of cougar movements using radio collars.

Recent land acquisitions and national forest management changes have dramatically improved the outlook for habitat quality near the project. In recent years, purchases, donations, and exchanges have brought more than 50,000 acres of land valued at $200 million into public ownership and protection. The Forest Service is committing to additional habitat restoration, such as road removal.

In light of these changes to the landscape and the large investment of the crossing structures, the coalition is acting to contribute to the data collection of current and future wildlife usage of habitat in the project vicinity. The coalition has sponsored digital remote cameras that have been installed at proposed crossing structure locations to gather still photograph and video images of wildlife moving through the area. These cameras are maintained by coalition volunteer teams, and data is shared through the website. This winter the coalition has launched a partnership with the Wilderness Awareness School to begin snow tracking monitoring at selected proposed crossing structure locations to compliment our current remote camera program. Both of these programs have begun this year, and are intended for long term monitoring.

The coalition has grown out of a history of grassroots activism and collaboration around the Central Cascades region. Citizen involvement has played a critical role in the management policies of this area. The I-90 project will be a greater success due to the high level of attention, input, and assistance received from the public. Public involvement peaked in the spring of 2005 with the release of the Draft Environmental Impact Statement bringing in thousands of public comments. Involvement continues throughout the state through efforts of education such as our annual Bridging Futures contest, advocacy, and monitoring by the coalition.