Darin, the county is actually restoring part of the Slough to its old bed at Marymoor Park, and all the tree-planting efforts are very positive. What they won't do is restore boulders and rock and put tons of woody debris in the river to make it naturally riffle and pool. I did use to fish the Slough a little for steelhead, and had one on once. A decent hatchery run continued until probably the late 70s. But the river had been ruined by the Corps before I was an adult. My father used to fish it a bit and caught steelhead. A buddy of his caught a 17-pounder probably in about 1957. Tight lines!