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Oregon / Washington

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.

Click on titles to navigate to specific documents. For ease of function, the South Fork Alsea Watershed Analysis and the maps are separate Adobe Acrobat PDF files.

South Fork Alsea Watershed Analysis (PDF) Complete document

Map Title Number
Subwatersheds and Major Streams (PDF) 1
Ownership and Land Use (PDF) 2
Landslide Potential and High Risk Roads (PDF) 3
Seral Stage Distribution on BLM Lands (PDF) 4
Vegetation Classes from Landsat Imagery (PDF) 5
Special Habitats Based on Soil Types and Plant Communities (PDF) 6
Late Seral and Old-Growth Habitat Conditions (PDF) 7
Suitable Habitat Conditions within Provincial Home Range Circles of
Spotted Owl Sites
Stream Temperature Risk Classification (PDF) 9
Large Woody Debris Potential for Fish-Bearing Streams (PDF) 10
Large Woody Debris Potential in Headwater Streams (PDF) 11
Chinook and Coho Salmon Distribution (PDF) 12
Steelhead and Cutthroat Trout Distribution (PDF) 13
Riparian Reserves on BLM Managed Lands (PDF) 14
Harvest Opportunities within General Forest Management Area (PDF) 15
Density Management Opportunities within Late Successional Reserves (PDF) 16