Wildlife bridges could make I-90 more wildlife-friendly 

06:57 PM PDT on Friday, June 10, 2005

From KING 5 Staff and Wire Reports

SEATTLE – State transportation officials have come up with a plan to provide safe passage for animals crossing one of Washington's busiest roadways. It's the out-of-the-box plan to make I-90 more wildlife-friendly.

On an average day, 27,000 vehicles cross the busy section of Interstate 90 near Snoqualmie Pass. But there is another, less visible form of traffic there.

"This is the middle of a wildlife corridor between Alpine Lakes Wilderness and Mount Rainier National Park, and cutting right through the middle of it is Interstate 90," said Charlie Raines, I-90 Wildlife Bridges Coalition.

And when the two corridors collide, there can be horrible results, like the accident that killed four people last year on I-90 when a car collided with an elk.

To handle the human traffic, state transportation officials rolled out a plan showing a six-lane expansion on I-90 for 15 miles east of Snoqualmie Summit.

So while they're at it, they could expand some of the existing bridges and add new culverts to add a sort of highway underneath a highway – exclusively for animals. And in at least one place, they would add an overpass.

One of those overpasses actually exists in Canada, along with several underpassages for wildlife – and it works!

"The reduction is really dramatic. For elk in particular it's a 92 percent reduction in wildlife mortality," said Raines.

KING

A 1,200-foot land bridge could safely guide animals across the freeway.

And to find out if animals are using their safe passageways, researchers set up hidden cameras. They caught on tape bull elk ushering through the herd, mother and baby bears taking the safe route across the highway, and even cougars creeping under busy traffic.

The evidence is compelling enough for conservation groups to take the rare step of endorsing a highway expansion plan.

"A huge problem to be solved and a golden opportunity to fix it," said Raines.

The state says providing for wildlife during a highway expansion is much cheaper than trying to do it afterward.

If the I-90 expansion plan is approved, engineers say they can add the wildlife passages for a small percentage of the total project cost.

The more expensive option for improving the interstate would widen it from four to six lanes, straighten some curves, stabilize slopes and adjust lanes to avoid avalanches.

Estimated costs range from $410 million to $980 million. The 2005 Legislature committed $387.7 million toward the project, which is scheduled to begin in 2011 and last up to seven years.

The state DOT says the wildlife corridors could cost between $25 million and $100 million.

Wildlife bridges and underpasses have been used for years successfully in Scandinavian countries.