ISBN: | 978-5-5105-3178-7 |
High Quality Content by WIKIPEDIA articles! Johnson Creek is a 25-mile (40 km) tributary of the Willamette River in the Portland metropolitan area of the U.S. state of Oregon. Part of the drainage basin of the Columbia River, its watershed consists of 54 square miles (140 km2) of mostly urban land occupied by about 175,000 people as of 2006. Passing through the cities of Gresham, Portland, and Milwaukie, the creek flows generally west from the foothills of the Cascade Range through sediments deposited by glacial floods on a substrate of basalt. Though polluted, it is free-flowing along its main stem and provides habitat for salmon and other migrating fish.