South Fork Alsea River

The South Fork Alsea watershed encompasses approximately 40,300 acres in the central Oregon Coast Range approximately 20 miles southwest of Corvallis. The geology of the watershed is composed of a mixture of volcanic and sedimentary rocks. It is highly dissected by intermittent and perennial streams which feed into the S. F. Alsea River. Streams in the upper portions of the watershed have higher gradients with steep, high ridges separating the streams. Lower portions of the river basin have broad, flat alluvial bottoms which were likely the focus of early settlement (both Native American and post-European) and, to this day, are the most populated portions of the watershed. They have a history of fishing, logging, and agriculture.

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