SNOQUALMIE PASS, Wash. (AP) — Before descending the Cascade Mountains on its final stretch to Seattle, Interstate 90 cuts through a mountain pass of old growth forests and wetlands. For countless wildlife species, the busy highway is a border, constraining their movements and posing a fatal risk should they dare to cross it. "Everything from an elk down to a small salamander, they need to move to find food, to find mates, to find new places to live as their populations expand or just when conditions change, like a fire breaks out," said Jen Watkins of Conservation Northwest. Soon, animals will have a safer option for crossing the road: They'll be able to go above it. Washington state is finishing work on its largest wildlife bridge.