Kelley Creek, a small tributary of Johnson Creek, provides much needed cold water refuge for salmonids. Johnson Creek is one of the last free-flowing streams in Portland. It has a small independent population of steelhead, which are currently listed under the Endangered Species Act. In the 1930’s, the Works Progress Adminstration (WPA) channelized, straightened, and rock-lined much of Johnson Creek. Because of these changes, salmonid habitat was degraded and water quality impaired due to siltation, increased water temperatures, and severe flooding.