|Name origin: An Indian word, Tlats-kani, referring to a point in the Nehalem Valley but applied by whites to two rivers in the area, the Clatskanie and the Klaskanine|
|Source||Northern Oregon Coast Range|
|- elevation||1,340 ft (408 m) |
|- location||Clatskanie, Columbia County, Oregon|
|- elevation||16 ft (5 m) |
|- coordinates||Coordinates: |
The Clatskanie River is a tributary of the Columbia River, approximately 25 miles (40 km) long, in northwestern Oregon in the United States. It drains a timber-producing area in the foothills of the Northern Oregon Coast Range north-northwest of Portland.
It rises in eastern Columbia County, approximately 10 miles (16 km) west of St. Helens on the northern slopes of Bunker Hill. Major tributaries include Carcus Creek and the North Fork of the Clatskanie, which converge at Swedetown. The North Fork rises at Apiary. It flows generally north-northwest through the Clatsop State Forest, past Clatskanie. The Clatskanie River converges with Conyers Creek and Beaver Creek near Clatskanie and then it enters a slough on the Columbia from the south approximately 5 miles (8.0 km) east of Westport.
The river is named for the Tlatskanai, an Athabascan tribe of Native Americans who lived in the valley of the nearby Nehalem River at the time of the arrival of Europeans in the early 19th century. There is also a Klaskanine River in Clatsop County which was really named for the same reason. The names as used by the natives did not apply to the respective rivers, but applied to the path, route or trail by which one could get to the customary tribal area of the Tlatskanai.
- McArthur, Lewis A.; McArthur, Lewis L. (2003). Oregon Geographic Names (seventh ed.). Portland, Oregon: Oregon Historical Society Press. pp. 206–07 and 542–43. ISBN 0-87595-277-1.
- Source elevation derived from Google Earth search using GNIS source coordinates.
- "Clatskanie River". Geographic Names Information System (GNIS). United States Geological Survey. November 28, 1980. Retrieved August 16, 2009.
- McArthur, Lewis A.; Lewis L. McArthur (1984) . Oregon Geographic Names (6th ed.). Portland, Oregon: Oregon Historical Society Press. p. 182. ISBN 0-87595-237-2.