Duncan River


The Duncan River is a long river in the Canadian province of British Columbia. Its drainage basin is in area. It is part of the Columbia River basin, being tributary via Kootenay Lake to the Kootenay River, which is a tributary of the Columbia River. It forms part of the boundary between the Selkirk Mountains, to its west, and the Purcell Mountains, to its east.

Course

The Duncan River originates at a pass between Mount Duncan of the Selkirk Mountains and Silent Mountain in the Purcell Mountains and flows south through the Purcell Trench. It flows into Duncan Lake, a natural lake that has been enlarged by Duncan Dam. A short distance below the dam, the Duncan River is joined by the Lardeau River, its largest single tributary. From here the river continues south to join the Kootenay River at the North Arm of Kootenay Lake.

History

Duncan River was named for John Duncan, a prospector and candidate for the colonial Legislative Council from the Kootenay Land District in the 1866.
On some early maps Duncan Lake is shown with the name "Upper Kootenay Lake" or "Howser Lake", but since 1912 the name Duncan has prevailed.
Before Duncan Dam was built the river served as the main navigation route into the valley, used by mining and logging industries. The route was navigable via Kootenay Lake as far as Bonner's Ferry, Idaho, on the Kootenai River.
Duncan Dam was finished in 1967, the first of the three Canadian Columbia River Treaty dams to be built. Its purpose is to regulate flow into Kootenay Lake, in coordination with Libby Dam, to assure sufficient water flow for the Kootenay Canal and Corra Linn Dam projects. Duncan Dam does not produce any electricity. Duncan Lake, originally in length, is now long.