Churchill Falls

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**Churchill Falls**


Location	Labrador
Type	Segmented Block
Total height	245 ft (75 m)
Watercourse	Churchill River

Churchill Falls are waterfalls named after former British Prime Minister, Winston Churchill. They are 245 ft (75 m) high, located on the Churchill River in Newfoundland and Labrador, Canada.

Four miles (6 km) above the falls, the Churchill River narrowed to 200 ft (60 m) and negotiated a series of rapids before dropping into MacLean Canyon, from which sheer cliffs rise several hundred feet on either side. The river flowed 12 miles (19 km) through the canyon over a series of rapids. The total drop from the rapids above the main falls to the end of MacLean Canyon is 1,038 ft (316 m).

Water flows down the falls less than once a decade, during spring thaw or periods of exceptional rains.

Since 1970, the waters of the Churchill River have been diverted into the nearby Churchill Falls hydroelectric power station. The Churchill Falls power station has the second largest hydroelectric-generating capacity in North America (5,428 MW installed, expandable to about 6,300 MW) and is also the second largest underground power station in the world, after the Robert-Bourassa generating station in northern Quebec.

1 Discovery and study
2 Hydroelectric power project
3 Aboriginal rights
4 Project Facts
5 Specifications and statistics
- 5.1 Power station
6 Churchill Falls Sport Fishing
7 See also
8 External links

[edit] Discovery and study

Churchill Falls were first explored in 1839 by John McLean, a trader of the Hudson's Bay Company. MacLean named the river the Hamilton River, after Newfoundland Governor, Sir Charles Hamilton. The falls were known as Grand Falls until 1965 when both names were changed to the Churchill River and Churchill Falls to honour the former British Prime Minister, Sir Winston Churchill.

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.

[edit] Hydroelectric power project

In 1915, Wilfred Thibaudeau surveyed the Labrador Plateau and engineered a channel scheme which could be used to divert the water from the river before it arrived at the falls. The scheme would use the natural capacity of the basin, thereby eliminating the need for the construction of massive dams.

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:

the inhospitable terrain
severe climatic conditions
geographic remoteness
long distance transmission requirement
the lack of markets for such a large block of power

In August, 1949, Joseph R. 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 1,000 feet (300 m) underground. Its final proportions are huge: in height it equals a 15-storey building, its length is three times that of a football field. When completed, it housed 11 generating units, with a combined capacity of 5,428 MW (more than 7,000,000 horsepower). Water is contained by a reservoir created not by a single large dam, but by a series of 88 dikes that total 64 km (40 miles) 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 2,200 mi² (5,700 km²) and provides storage area for more than 1,000,000,000,000 ft³ (28,000,000,000 m³) 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 23,300 mi² (60,300 km²). Once Orma and Sail lakes' outlets were diked, it added another 4,400 mi² (11,400 km²) of drainage for a total of 27,700 mi² (71,700 km²). This makes the drainage area larger than the Republic of Ireland. Studies showed this drainage area collected 410 mm (16 in) of rainfall plus 391 cm (154 in) of snowfall annually equalling 12.5 mi³ (52 km³) 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."

[edit] Aboriginal rights

The Churchill Falls hydroelectric plant development was undertaken in the absence of any agreement with the aboriginal Innu people of Labrador. Despite the flooding of over 5,000 km² of traditional hunting and trapping lands, no compensation was ever offered.

[edit] Project Facts

Churchill Falls power plant is the second largest hydroelectric plant in North America, with an installed capacity of 5,428 MW.
Churchill Falls was, at the time of its construction, the largest underground power station in the world. (The Robert-Bourassa power station in Quebec currently holds the record, both for installed capacity and volume of the main underground hall).
The powerhouse is 972 ft long, up to 81 ft wide and 154 ft high from the bottom to the top (296 m by 25 m by 47 m). The height would be equivalent to a 15-story building, as long as 3 football fields and is hollowed from solid granite. To strengthen walls and ceiling, more than 11,000 rock bolts (steel rods 15 to 25 ft (5 to 8 m) long) were used in the three major chambers.
To move the 2.3 million yd³ (1.9 million m³) of rock that was excavated from the underground caverns, it required 5 million pounds (2,300 tonnes) of explosives. This material was used in roads, building the town site, and as dike material.
The turbine wheels are cast of stainless steel and weigh 80 short tons (70 tonnes) which is a world record for the largest stainless steel casting ever made.
During construction, 730,000 short tons (660,000 tonnes) of material, equipment and fuel were moved to the site.
The natural catchment area for the Churchill River covers over 23,300 mi² (60,300 km²).
By diverting the water from the Ossokmanuan Reservoir the total catchment area became 27,700 mi² (71,700 km²).
Total natural drop of the water starting at Ashuanipi Lake and ending at Lake Melville is 1,735 ft (529 m). As a comparison, the water starting 30 km (20 mi) upriver until it enters the power plant drops over 1,000 ft (300 m).
There is no big dam associated with this hydropower plant. There are 88 dikes to contain the reservoir, the longest is 6.1 km (3.8 miles) and the highest is 36 m (117 ft). The total length of all dikes is 64 km (40 miles) and contains 26 million yd³ (22,000,000 m³) of embankment material.
After five years of non-stop field work by approximately 6,300 workers and costing $950,000,000 (1970) construction culminated on December 6, 1971 when the first two generating units began delivering power, five months and three weeks ahead of schedule.
Currently Churchill Falls makes almost 1% of the world's hydroelectric power.
Newfoundland and Labrador recently announced a call to develop the Lower Churchill Project. This is, in fact, a number of small projects which includes a 2,000 MW dam at Gull Island, an 824 MW dam at Muskrat Falls, 1,000 MW upgrade to the existing facility at the Churchill Falls power plant. This would increase the present power production capability by an extra 4,000 MW for a total of 9,252 MW for the entire Churchill River hydroelectric complex.

[edit] Specifications and statistics

[edit] Power station

Churchill Falls generating station
Year commissioned:	1971
Installed capacity:	5,428 MW
Annual energy output:	35,000 GWh
Number of turbines:	11
Turbine capacity:	493.5 MW
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:	312.4 m
Maximum tailrace discharge:	49,000 ft³/s (1,390 m³/s)
Powerhouse:	296 m length, 25 m width, 47 m height, 310 m below ground
Tailrace tunnels:	2 × 1,691 m, 14 m width, 19 m height
Penstocks:	11 × 427 m length, 20 ft (6.1 m) diameter
Cable shafts:	11 × 7 ft (2.13 m) diameter, 263 m deep
Dikes:	88; 64.4 km total length, 9 m average height, 36 m maximum height
Size of reservoir:	6,988 km²
Total catchment area:	71,700 km²

[edit] Churchill Falls Sport Fishing

14 Pound lake trout caught in the Churchill Falls reservoir lakes.

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, speckle trout and northern pike. The ideal growing environment leads to lake trout weighing in excess of 20 pounds, speckle trout larger than 6 pounds, and northern pike of comparably above average weights.