The Collawash River is a major tributary to the Clackamas River on the west slopes of the Cascade Range in northwest Oregon. The scenic segment flows through a narrow, steeply sloped, well-dissected canyon that contains several cliffs and talus slopes. The river flows over and around many rocks, through pools, and over one waterfall approximately 20-feet high.
March 30, 2009. From the headwaters of the East Fork of the Collawash River to Buckeye Creek.
The river provides excellent spawning habitat for anadromous fish throughout the segment. The steep cascade area located in the lower portion of the segment acts as a partial barrier for most anadromous fish, though some have been known to migrate beyond it. Rainbow trout is the major resident species of the river. Spring Chinook, winter and summer steelhead, and winter run coho are found within the lower end of the segment. The winter run coho is a rare native stock of salmon once found throughout the Columbia River drainage. This stock has been known to migrate above the falls.
In the recreational segment of the river there are a number of unstable earth flows. There is one area which could be considered a "textbook" example of a very active earth flow and could be easily interpreted.