Since 1970, the waters of the Churchill River have been diverted into the nearby Churchill Falls hydroelectric power station. Today water flows down the falls less than once a decade, during spring thaw or periods of exceptional rains. The Churchill Falls power station has the second largest hydroelectric-generating capacity in North America (installed, expandable to about ) and is also the second largest underground power station in the world, after the Robert-Bourassa generating station in northern Quebec.
In 1894, Albert Peter Low of the Geological Survey of Canada reached the Grand Falls during his study of the large number of iron ore deposits in western Labrador and northeastern Quebec.
In 1947, Commander G.H. Desbarats, under the direction of the Newfoundland Government, completed a preliminary survey that confirmed Thibaudeau's findings. However development did not proceed due to several reasons:
In August, 1949, Joey Smallwood, Premier of Newfoundland, had the opportunity to see Churchill Falls for the first time and it became his obsession to develop the hydroelectric potential of the falls. In 1953 British Newfoundland Development Corporation (Brinco) was formed to do extensive exploration of the untapped water and mineral resources. With the development of the iron ore mines in western Labrador and the construction of the Quebec North Shore and Labrador Railway (1954), development of Churchill Falls as a power source became feasible.
After years of planning, the project was officially started on July 17, 1967. The machine hall of the power facility at Churchill Falls was hollowed out of solid rock, close to underground. Its final proportions are huge: in height it equals a 15-storey building, its length is three times that of a Canadian football field. When completed, it housed 11 generating units, with a combined capacity of . Water is contained by a reservoir created not by a single large dam, but by a series of 88 dikes that total in length.
Once all the dikes were in place, it provided a vast storage area which later became known as Smallwood Reservoir. This reservoir covers and provides storage area for more than of water.
The drainage area for the Churchill River includes much of western and central Labrador. Ossokmanuan Reservoir which was originally developed as part of the Twin Falls Power System also drains into this system. Churchill River's natural drainage area covers over . Once Orma and Sail lakes' outlets were diked, it added another of drainage for a total of . This makes the drainage area larger than the Republic of Ireland. Studies showed this drainage area collected of rainfall plus of snowfall annually equalling of water per year; more than enough to meet the project's needs. Construction came to fruition on December 6, 1971, when Churchill Falls went into full-time production.
The generating station is owned and operated by the Newfoundland and Labrador Hydro company.
The division of profits from the sale of electricity generated at the plant have proven to be a very sensitive political issue in Newfoundland and Labrador, with many considering the share accorded to Hydro-Québec "an immense and unconscionable windfall.
| Churchill Falls generating station | |
|---|---|
| Year commissioned: | 1971 |
| Installed capacity: | |
| Annual energy output: | |
| Number of turbines: | 11 |
| Turbine capacity: | |
| Type of turbine: | vertical Francis type, 200 rpm |
| Generators: | 15 kV, 526,315 kV·A |
| Transformers: | 14.75 kV/240 kV, rated at 5,500 MV·A |
| Net rated head: | |
| Maximum tailrace discharge: | 49,000 ft³/s (1,390 m³/s) |
| Powerhouse: | length, width, height, below ground |
| Tailrace tunnels: | 2 × , width, height |
| Penstocks: | 11 × length, diameter |
| Cable shafts: | 11 × diameter, deep |
| Dikes: | 88; total length, average height, maximum height |
| Size of reservoir: | |
| Total catchment area: | |
The community of Churchill Falls has been a popular destination for hobby and sport fisherman for many years. The construction of the hydroelectric infrastructure has created large, enclosed freshwater environments which are populated by several species of fish, including lake trout, brook trout (speckled trout) and northern pike. The ideal growing environment leads to lake trout weighing in excess of , speckled trout larger than , and northern pike of above average weights.