I-90 improvements may include wildlife aid

SEATTLE – Widening a stretch of Interstate 90 that cuts through the Cascade Range also could bring pathways, culverts and a 1,200-foot land bridge to help guide animals across the pavement, officials say.

The proposed pathways are part of the state’s options for improving I-90 between the top of Snoqualmie Pass and the town of Easton, 15 miles to the east. Scientists say the section of freeway is a bottleneck for animals, which are pushed by development from the west and east.

“Each of these is in areas where biologists say wildlife is likely to use them – because they’ve seen roadkill there, or the habitat is there,” state Department of Transportation spokesman Mark Pettit told the Seattle Times.

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.

Environmentalists and federal land managers have raised millions of dollars and purchased tens of thousands of acres of private land in the central Cascades in recent years to preserve a link between wilderness areas north and south of I-90.

When the state began planning the freeway construction project, conservationists and the U.S. Forest Service began seeking a way to improve wildlife access.

The animal crossings would particularly aid carnivores facing potential extinction, such as lynx and gray wolves, said Patty Garvey-Darda, a Forest Service biologist.

“It’s a pivotal project,” William Meyer, a biologist with the state Fish and Wildlife Department in Ellensburg, told the Seattle Post-Intelligencer.

The state DOT says the wildlife corridors could cost between $25 million and $100 million. State Senate Minority Leader Bill Finkbeiner, R-Kirkland, wonders if the animal paths are worth the added expense.

“I really question the cost-benefit of this,” he said. “It seems to me that there’s got to be cheaper ways to address this problem.”

Doug MacDonald, the state transportation secretary, acknowledged that the wildlife plans “will require a significant investment.” But he said they could improve driver safety, and pointed to a crash last year outside North Bend that killed four people when a car hit an elk.

Because I-90 cuts through the Wenatchee National Forest, “even if we didn’t propose it, the Forest Service still would have made us do something like this,” MacDonald said.

Officials say there are relatively few other examples of wildlife-friendly highways. One is the “Alligator Alley” pathway in Florida.

“It’s a growing science, and it’s really cool to see what they’re doing on I-90,” said Amanda Hardy, a research ecologist at Montana State University’s Western Transportation Institute. “Washington is really in the forefront in their efforts.”