Archway installed for I-90 wildlife bridge

Conservation Northwest / Sep 21, 2016 / I-90 Wildlife, Wildlife Crossings

Construction is moving forward on a major project to improve motorist safety and reconnect the north and south Cascades for wildlife

An average of 28,000 vehicles travel Washington’s busiest mountain pass each day. It’s a route that’s vital for communities on both sides of the Cascades, as well as for commerce, agriculture, recreation and much more. But for wildlife from elk to wolves, Interstate 90 can be a killer.

Thankfully, help is on the way.

On Wednesday September 21, the Washington State Department of Transportation (WSDOT) and its contractors installed the first of two archways that will span six lanes of traffic on both directions of the interstate. It’s a significant milestone in the construction of I-90’s first “wildlife bridge”, the Keechelus Lake Wildlife Overcrossing (formerly named the Price-Noble Wildlife Overcrossing). When completed it will be the largest wildlife overcrossing in North America. Though such structures have been successful in other states and countries, it’s Washington’s first wildlife crossing over a highway or interstate.

“Today marks a historic moment in the I-90 Snoqualmie Pass East Project as the wildlife bridges move from concept to reality,” said Jen Watkins of Conservation Northwest. “Several underpasses already constructed in the project have been providing safe passage for wildlife, but the installation of the arches for the first I-90 wildlife overcrossing is an iconic symbol of the benefits the full 15-mile project will have for reconnecting the Cascades.”

View our Facebook album for more photos from the arch installation!

Watkins, one of our Conservation Associates, has been our point person on this project for years. She coordinates the I-90 Wildlife Bridges Coalition and I-90 Wildlife Watch, two collaborative efforts administered by Conservation Northwest, as well as supporting the advocacy and science necessary to make these monumental crossings a reality.

The site where dozens of 40,000 pound concrete pieces were being lifted into place to form the archway is located east of Snoqualmie Pass past Keechelus Lake near Price Creek. Extensive wildlife monitoring, winter snow tracking and other research around Price Creek during the project’s planning phase identified the area as a good location for increased connectivity due to diverse wildlife species regularly using the area. Animals including elk, mule deer, black bears and cougars were naturally moving through the Price Creek area. It’s also a logical crossing for wildlife around the east end of Keechelus Lake.

In addition to locating the bridge and other wildlife crossings at specific high-traffic locations identified during planning, eight foot tall fencing on either side of I-90 throughout the project area will help direct wildlife to the crossings. Results from other states and Canada have shown similar wildlife over- and undercrossings to be very successful at providing wildlife safe passage and preventing collisions between vehicles and large animals. The structures can work particularly well for animals like elk and mule deer, which often pass on travel routes from mothers to calves or fawns during their annual winter and spring migrations.  

The construction of the first wildlife bridge is part of Phase 2 of WSDOT’s I-90 Snoqualmie Pass East Project, a 15-mile corridor improvement effort from Hyak to Easton that began in 2009. The project builds a safer more efficient and reliable transportation corridor to facilitate the movement of people, freight, fish and wildlife by adding a lane in each direction, stabilizing rock slopes, adding new bridges and culverts and constructing wildlife crossings.

In addition to the overcrossing, Phase 2 also includes three other wildlife underpasses or culvert expansions and major roadway improvements including raised bridges that allow avalanches to pass under the interstate. Phase 1 of the project included two large wildlife undercrossings at Gold Creek at the west end of Keechelus Lake, as well as two other undercrossings, Rocky Run and Resort Creek. All four undercrossings provide safe passage for wildlife large and small, as well as ducks and other waterfowl, amphibians and fish including endangered bull trout. Phase 3 of the project will include another major wildlife overcrossing west of the town of Easton, as well as additional wildlife undercrossings, culvert expansions and roadway improvements. Phase 3 of the project was fully funded during the 2015 legislative session and will begin in several years.

“Were excited that the wildlife overcrossing is being constructed”, said Brain White, WSDOT’s Assistant Regional Administrator for Construction and Development. “This project has been a long time in study, planning and design. To see something finally being built is really a good feeling. And knowing that you’re connecting the habitats that wildlife need while keeping wildlife off the roadway, it really makes you feel good.”

White is hopeful that wildlife including elk, which studies have shown can be averse to using enclosed undercrossings and prefer the more open and natural feel of overcrossings, will be using the Keechelus Lake wildlife bridge soon after construction is complete.  Once the crossings are finished, they’re expected to be used by a variety of species, from small mammals like pikas to endangered species like wolves and wolverines.

Elk and deer are hit by vehicles on I-90 around Snoqualmie Pass each year, causing a significant financial toll and in some cases serious injury or even death. In early 2015 the first wolf confirmed back in Western Washington in nearly 80 years was hit and killed on the interstate just west of Snoqualmie Pass. With wolverines recovering in the North Cascades and expanding their range southward, losing just one of these animals to a vehicle collision would be a loss for this endangered species.

“We did the Gold Creek bridges up near Hyak, and within a year we saw wildlife using them once they learned it was a safe passage area,” said White. “I think transportation projects in general, it used to be that we just tried to design them for cars and trucks. Now we’re looking at the surroundings we’re in and trying to come up with context-sensitive solutions. This project fits in with the natural environment around it and that’s what we’re really proud of;  working with our partners designing a project that meets everyone’s needs.”

A design visualization of the completed Keechelus Lake Wildlife Overcrossing. Source: WSDOT

Help us advocate for safe wildlife crossings on I-90 and other Northwest highways by making a donation today.

Advocacy from the I-90 Wildlife Bridges Coalition, Conservation Northwest, Forterra, Sierra Club, and other partners helped ensure that the wildlife crossings component was included in the larger highway improvement project. The entire project is budgeted at just under $1 billion. The cost of the first wildlife overcrossing is $6.2 million. The first wildlife overcrossing is expected to be complete by the fall of 2018.