The Nespelem River is a northern tributary

Tributary

A tributary or affluent is a stream or river that flows into a main stem river or a lake. A tributary does not flow directly into a sea or ocean...

 of the Columbia River

Columbia River

The Columbia River is the largest river in the Pacific Northwest region of North America. The river rises in the Rocky Mountains of British Columbia, Canada, flows northwest and then south into the U.S. state of Washington, then turns west to form most of the border between Washington and the state...

, in the U.S. state

U.S. state

A U.S. state is any one of the 50 federated states of the United States of America that share sovereignty with the federal government. Because of this shared sovereignty, an American is a citizen both of the federal entity and of his or her state of domicile. Four states use the official title of...

 of Washington. It is completely contained within Okanogan County and the Colville Indian Reservation

Colville Indian Reservation

The Colville Indian Reservation is an Indian reservation in the north-central part of the U.S. state of Washington, inhabited and managed by the Confederated Tribes of the Colville Reservation, which is recognized by the United States of America as an American Indian Tribe...

.

The name "Nespelem" is said to come from the Indian word nesilim, meaning "flat land".

Course

The Nespelem River originates in eastern Okanogan County and flows south. It collects several minor tributaries including Stepstone Creek, North Star Creek, and Armstrong Creek, before passing by the town of Nespelem, Washington

Nespelem, Washington

Nespelem is a town in Okanogan County, Washington, United States. The population was 236 at the 2010 census. The town is located on the Colville Indian Reservation. The name Nespelem is derived from a local Indian term meaning "large flat meadow".-History:...

, the headquarters of the Colville Indian Reservation.

Below the town, the Nespelem River turns west. The Little Nespelem River joins just before the river empties into the Columbia River. This reach of the Columbia River is several miles below Grand Coulee Dam

Grand Coulee Dam

Grand Coulee Dam is a gravity dam on the Columbia River in the U.S. state of Washington built to produce hydroelectric power and provide irrigation. It was constructed between 1933 and 1942, originally with two power plants. A third power station was completed in 1974 to increase its energy...

 and many miles above Chief Joseph Dam

Chief Joseph Dam

The Chief Joseph Dam is a concrete gravity dam on the Columbia River, upriver from Bridgeport, Washington, USA. The dam was authorized as Foster Creek Dam and Powerhouse for power generation and irrigation by the River and Harbor Act of 1946...

. The impounded Columbia River behind Chief Joseph Dam, into which the Nespelem River flows, is called Rufus Woods Lake.