Spokane River – Idaho
The Spokane River is a tributary of the Columbia River, approximately 111 miles (179 km) long, in northern Idaho and eastern Washington in the United States. It drains a low mountainous area east of the Columbia, passing through the city of Spokane, which shares its name with the river. Heavily used for irrigation and drinking water, its watershed comprises a region of extensive farming and timber production. The lowered water levels in the river have resulted in an ongoing pollution crisis and a political struggle over its resolution.
The Spokane River’s entire drainage basin is about 6,240 square miles (16,200 km2) large, of which 3,840 square miles (9,900 km2) are above Post Falls Dam at the outlet of Coeur d’Alene Lake. Its mean annual discharge is 7,946 cubic feet per second (225 m3/s).
The Spokane River rises out of Lake Coeur d’Alene in the Idaho Panhandle, draining from the northwest corner of the lake near the city of Coeur d’Alene. It flows west approximately 25 mi (40 km) into east central Washington to Spokane, where it receives Latah Creek from the south.
From Spokane it flows northwest, receiving the Little Spokane River from the east approximately 10 mi northwest of the city. It flows in a zigzag course along the southern edge of the Selkirk Mountains, forming the southern boundary of the Spokane Indian Reservation, where it is impounded by the Little Falls Dam, and to form Long Lake, a 15 mi (24 km) reservoir. It joins Franklin D. Roosevelt Lake on the Columbia from the east at Miles. The site of historic Fort Spokane is located at the mouth of the river on the Columbia.