The Salmo River is a 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 Pend d'Oreille River

Pend Oreille River

The Pend Oreille River is a tributary of the Columbia River, approximately long, in northern Idaho and northeastern Washington in the United States, as well as southeastern British Columbia in Canada. In its passage through British Columbia its name is spelled Pend-d'Oreille River...

 in the Canadian province

Provinces and territories of Canada

The provinces and territories of Canada combine to make up the world's second-largest country by area. There are ten provinces and three territories...

 of British Columbia

British Columbia

British Columbia is the westernmost of Canada's provinces and is known for its natural beauty, as reflected in its Latin motto, Splendor sine occasu . Its name was chosen by Queen Victoria in 1858...

. The Salmo River is part of the Columbia River drainage basin, being a tributary of the Pend d'Oreille River, which flows into 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...

.

The river's drainage basin

Drainage basin

A drainage basin is an extent or an area of land where surface water from rain and melting snow or ice converges to a single point, usually the exit of the basin, where the waters join another waterbody, such as a river, lake, reservoir, estuary, wetland, sea, or ocean...

 is 1300 square kilometres (501.9 sq mi) in area. Its mean annual discharge

Discharge (hydrology)

In hydrology, discharge is the volume rate of water flow, including any suspended solids , dissolved chemical species and/or biologic material , which is transported through a given cross-sectional area...

 is 32.5 m3/s.

Course

The Salmo River originates in the mountains south of Nelson

Nelson, British Columbia

Nelson is a city located in the Selkirk Mountains on the extreme West Arm of Kootenay Lake in the Southern Interior of British Columbia, Canada. Known as "The Queen City", and acknowledged for its impressive collection of restored heritage buildings from its glory days in a regional silver rush,...

. it flows generally south, passing Salmo, British Columbia

Salmo, British Columbia

Salmo is a village in the West Kootenay region of southeastern British Columbia, Canada. It is located in the Salmo River Valley, surrounded by the Selkirk Mountain range....

before joining the Pend d'Oreille River just north of the US-Canada border.