Overpass For Squirrels Under Fire Plan Called Vague, Risky By Environmentalists

A proposed $2 million overpass to allow a threatened species of squirrel to cross a planned highway safely is coming under fire from environmental officials who say the plan is vague and risky.

The overpass, suggested by Pierce County as a way to preserve habitat of the Western gray squirrel, would be part of a proposed $50 million highway that would link Interstate 5 with Washington 7 between Fort Lewis and McChord Air Force Base.

About 200 of the squirrels live on Fort Lewis, and they are the last of their kind west of the Cascade Range in Washington, state Fish and Wildlife Department officials say.

The county and its consultant, Parametrix of Kirkland, say the squirrel overpass would function exactly as a freeway overpass for vehicles. The on- and off-ramps, however, would be hillsides, and the bridge would be covered with plants - a re-created forest floor above the highway.

However, neither engineers from Parametrix nor the county have hammered out details of the plan. Still undecided are the plants and trees that might cover the overpass and the adjacent slopes, or even how the bridge would support the foliage.

“It’s very expensive and experimental,” said Elizabeth Rodrick, Fish and Wildlife’s wildlife program manager for the south Puget Sound region. “With a threatened species, it’s pretty unwise to spend that kind of money on something we don’t know whether it would work or not.”

Wildlife crossings aren’t uncommon in the state. Near North Bend on Interstate 90, elevated sections of the freeway allow deer and other animals to trot underneath. More unusual are large pipes, or underground tunnels, which let frogs and other reptiles avoid being squashed.

The idea of a squirrel overpass is “worth exploring,” said David Mattern of Parametrix, the engineer who came up with the idea.

“These things are difficult when they haven’t been done to know what the outcome will be,” Mattern said.

The absence of proof, however, is what stalled the environmental study from its December due date.

Resource officials argue it would split the squirrels’ habitat, leaving one area smaller than the other and thus tougher for those animals left there.

Besides, squirrels aren’t likely to brave the open landscape and traipse across an unknown form like a bridge, they said. The trek would also make the squirrels more vulnerable to predators.