West Kootenay Power and Light Company was incorporated in 1897. Its first project was to build a hydroelectric power station on the Kootenay River near where it joins the Columbia River and then build a transmission line through the rugged terrain down river and up the mountainsides to Rossland. This resulted in what was then the longest and highest voltage transmission line in the world. At 20,000 volts, the line would set new Canadian transmission records and would be the first in the world through alpine terrain.

The first hydro electric generators at Bonnington Falls supplied power to Rossland which became a boomtown in the 1890s. About 7,000 people set up residence in the alpine city along with 42 saloons, 17 law firms and 3 breweries. More than $2 billion worth of gold and other ore was produced and processed at the foot of the mountain. The Bonnington to Rossland project took just under a year, and on July 15, 1898, 500 lights were shining in Rossland.

West Kootenay Power and Light Company's first general manager was Lorne Campbell, who was brought in to supervise the installation of certain equipment at the Lower Bonnington project. Upon its completion, he set in motion what became a long range program to make full use of the Kootenay River's potential. Construction of the Upper Bonnington Plant began in 1905 and was later completed in 1907. The power plant project itself included the largest single piece of concrete construction in British Columbia up to that time.

With the smelter in Trail expanding and using huge amounts of power for its electrolytic processes and the onset of World War I, West Kootenay Power and Light Company had to change its business outlook and structure. Cominco acquired a controlling interest in West Kootenay Power and Light Company to ensure an adequate power supply for war time production demands. This meant that additional generating units were needed to be installed in the Upper Bonnington plant.

During this period, Cominco ranked as one of the world's major producers of lead and zinc. West Kootenay Power and Light Company kept pace with Cominco's power requirements with the construction of the South Slocan Plant, which was completed in 1929.

In addition to supplying the needs of the smelter at Trail, the system's domestic service expanded steadily over the years reaching Kelowna and Princeton in 1922 and supplying Creston in 1933. This made the construction of another hydroelectric facility necessary. In 1932 the completion of the Cora Linn Dam meant the needs of power demand could be met by the growing communities requesting this service.

In 1951, West Kootenay Power and Light Company completed an 86 mile line from South Slocan to Cominco's operation at the Sullivan Mine in Kimberly. A branch line was also created down the east side of Kootenay Lake to meet increasing domestic demand in the Creston and surrounding area.

Construction began on the Waneta power project at the mouth of the Pend d'Oreille River where it joins the Columbia River south of Trail in 1952. This was the last and largest station built in the system by West Kootenay Power and Light Company. In 1964 the Columbia River Treaty was ratified by the United States and Canada and major hydroelectric developments, flood control and water storage were started along the Columbia River.

In 2004 Fortis Inc. acquired all distribution, transmission, and generation assets of the West Kootenay Power and Light Companby re-named it FortisBC Inc.