| Middle Santiam River | |
| Name Etymology: | Kalapuya tribe that lived near the river until removal to the Grande Ronde Reservation[1] |
| Map Size: | 300 |
| Pushpin Map: | USA Oregon |
| Pushpin Map Size: | 300 |
| Pushpin Map Caption: | Location of the mouth of the Middle Santiam River in Oregon |
| Subdivision Type1: | Country |
| Subdivision Name1: | United States |
| Subdivision Type2: | State |
| Subdivision Name2: | Oregon |
| Subdivision Type4: | County |
| Subdivision Name4: | Linn |
| Length: | 39miles[2] |
| Source1: | Iron Mountain |
| Source1 Location: | Cascade Range, Willamette National Forest, Linn County, Oregon |
| Source1 Coordinates: | 44.4025°N -122.1619°W[3] |
| Source1 Elevation: | 4149feet[4] |
| Mouth: | South Santiam River |
| Mouth Location: | Foster Reservoir, Linn County, Oregon |
| Mouth Coordinates: | 44.4161°N -122.6339°W |
| Mouth Elevation: | 640feet |
| Basin Size: | 104sqmi[5] |
The Middle Santiam River is a tributary of the South Santiam River, 38.5miles long, in western Oregon in the United States. It drains a remote area of the Cascade Range east of Sweet Home in the watershed of the Willamette River.
It rises in the Cascades in eastern Linn County in the Willamette National Forest, about half a mile west of Iron Mountain. It flows briefly north, then generally west and southwest through the mountains and Middle Santiam Wilderness. In central Linn County it is impounded at the Green Peter Dam to form the Green Peter Reservoir. Approximately 4miles downstream from the dam it joins the South Santiam from the northeast as an arm of Foster Reservoir.
| location | geolocation | usgs map | |
|---|---|---|---|
| mouth, Foster Lake | 44.4162°N -122.634°W | Sweet Home | |
| junction Quartzville Creek Green Peter Lake | 44.4762°N -122.5006°W | Cascadia | |
| RM 15.4 | 44.5004°N -122.3956°W | Yellowstone Mountain | |
| RM 25.3 | 44.5171°N -122.2506°W | Chimney Peak | |
| source | 44.4026°N -122.162°W | Harter Mountain |
Named tributaries of the Middle Santiam River from source to mouth are Cougar, Holman, Lake, South Pyramid, Bachelor, Pyramid, Donaca, Jude, and Egg creeks, followed by Fitt, Chimney, Sixes, Bear, and Twin Falls creeks. Below that are Cougar, Crash, Maple, Elk, Knickerbocker and Cave creeks. Then come Tally, Quartzville, Whitcomb, Rumbaugh, and Thistle creeks. Finally are Green Peter, Little Bottom, Alder, Coal, and Lewis creeks.[6]