The La Grande-2-A is a hydroelectric power station on the La Grande River that is part of Hydro-Québec's James Bay Project. The station can generate 2,106 MW and was commissioned in 1991–1992. Together with the adjacent Robert-Bourassa generating station, it uses the reservoir and dam system of the Robert-Bourassa Reservoir to generate electricity.

La Grande-2-A Generating Station
Official name	La Grande-2-A
Locale	Quebec, Canada
Coordinates	53°46′46″N 77°32′54″W / 53.77944°N 77.54833°W / 53.77944; -77.54833 / 53.77944; -77.54833
Opening date	1992
Owner(s)	Hydro-Québec
Dam and spillways
Impounds	La Grande River
Spillway capacity	16,280 m3/s (574,923 cu ft/s)
Reservoir
Creates	Robert-Bourassa Reservoir
Capacity	6,170,000,000 m3 (2.18×1011 cu ft)
Surface area	2,835 km2 (1,095 sq mi)
Hydraulic head	138.5 m (454 ft)
Power station
Turbines	6 × 351 MW (Francis turbine)
Installed capacity	2,106 MW

The La Grande-3 Power Station or LG-3 is a hydroelectric dam on the La Grande River in northern Quebec, part of Hydro-Québec's James Bay Project. The La Grande-3 Power Station can generate 2,418 MW and was commissioned in 1982-1984. It generates electricity through the reservoir and dam system. The dam and reservoir both are named La Grande-3.

La Grande-3 Generating Station
Official name	La Grande-3
Locale	Quebec, Canada
Coordinates	53°43′47″N 75°58′06″W / 53.72972°N 75.96833°W / 53.72972; -75.96833 / 53.72972; -75.96833
Opening date	1984
Owner(s)	Hydro-Québec
Dam and spillways
Impounds	La Grande River
Spillway capacity	10,000 m3/s (350,000 cu ft/s)
Reservoir
Creates	La Grande-3 Reservoir
Surface area	2,420 km (1,504 mi)
Hydraulic head	79.2 m (260 ft)
Power station
Turbines	12 × 201.5 MW (Francis turbine)
Installed capacity	2,418 MW

The Daniel-Johnson Dam is a hydroelectric power plant in Canada, formerly known as Manic-5, is a multiple arch buttress dam on the Manicouagan River which creates Manicouagan Reservoir. The dam is composed of 14 buttresses and 13 arches and is 214 km (133 mi) north of Baie-Comeau in Quebec, Canada. The dam was constructed between 1959 and 1970 for the purpose of hydroelectric power production and supplies water to the Manic-5 and Manic-5-PA power houses. The dam is 214 m (702 ft) tall, 1,314 m (4,311 ft) long and contains 2,200,000 m³ (2,880,000 cu yd) of concrete, making it the largest dam of its type in the world.

Construction of Daniel Johnson Dam

Construction on the dam's support facilities began in 1959 and the river diversion tunnels and foundation preparation commenced in 1960. To divert the Manicoagan River, workers blasted and dug two 2,000 ft (610 m) long and 45 ft (14 m) diameter tunnels through the gorge's solid granite west wall. Workers used "jumbo" drilling platforms and the tunnels progressed 14 ft (4.3 m) each shift. To facilitate the river's diversion, two cofferdams were built. The first was a concrete arch upstream from the dam site which would block the river, forcing it into the diversion tunnels. The second cofferdam was downstream and prevented water from flowing back into the construction site. Each cofferdam was built on alluvial deposits (loose soil) so they needed to be watertight which was accomplished with either a grout curtain or deep supporting piles. Once the river was diverted, workers pumped the remaining water out between the two cofferdams in order to prepare the site for construction. Once drained, workers excavated the alluvial deposits between the cofferdams creating a long pit that was 150 ft (46 m) deep at the center. This pit was then filled with concrete in the summer of 1962. To prevent seepage in the dam's foundation, a grout curtain was injected in the bedrock and a drainage network with 2,400 ft (730 m) of tunnels was constructed just downstream of the dam to collect water that may seep through.

After the extensive preparatory works were complete, the first concrete for the dam was poured on October 3, 1962. Concrete was poured day and night but was halted during the winter because of freezing temperatures. To organize the pouring, the dam was split into 45 ft (14 m) plots and each was raised about 5 or 6 ft. at a time. Workers had about 150 days - before seasonal flooding - to construct the dam to a height of at least 250 ft (76 m). Before flooding began, engineers planned to seal the diversion tunnels and begin filling the reservoir. To speed the pouring process, concrete was poured in casts by buckets that moved along three cableways suspended above the construction site. The deadline was met within the 150 days and a total of 1,000,000 cu yd (760,000 m³) of concrete was poured. The dam was eventually completed in 1968.

Dam

The design of Daniel Johnson Dam was chosen for strength and economical reasons as it used less concrete or material than a gravity or embankment dam. The Daniel-Johnson Dam is a 214 m (702 ft) tall and 1,312 m (4,304 ft) long multiple-arch buttress dam. Of the dam's 14 total buttresses, the two that form the center arch are 530 ft (160 m) apart at their base while the others are about 250 ft (76 m) apart. At its thickest point, the center, the dam is 22.5 m (74 ft) wide while the crest can reach about 3 m (10 ft) wide. Pressure from water behind the dam is transferred from the dam's arches to its buttresses and lastly into the ground or its foundation.

The Daniel Johnson Dam was constructed with a high-quality concrete designed to withstand constant thawing and freezing associated with its environment. To further help the structure cope with the climate, engineers placed one inch steel reinforcing bars within the upstream and downstream faces of the dam. The concrete's strength in compression was initially 4,500 lbs. per square inch to meet an estimated 1,500 PSI within the structure. The upstream face of the dam was also coated in asphalt for protection against water. Despite the strength of the dam's concrete, two parallel inclined cracks were discovered on one of the arches shortly after construction.

Reservoir

The Daniel Johnson Dam impounded the Manicougan River, which filled the Earth's fifth largest confirmed impact crater, the Manicouagan crater, creating Manicouagan Reservoir. Coincidentally, the reservoir itself is the fifth largest in the world as well. The reservoir has a maximum depth of 350 m (1,150 ft) feet, mean depth of 85 m (279 ft) and contains 142 km³ (34 cu mi) of water. While draining an area of 29,241 km (18,170 mi), it has a surface area of 1,950 km² (750 sq mi) and shoreline of 1,322 km (821 mi).

The reservoir is a well known area for Atlantic salmon, lake trout and northern pike fishing, although tall trees flooded during the impoundment have not decomposed due to a lack of oxygen, which can sometimes interfere with the sport.

The priming of the reservoir also created a large artificial island in the center of the Manicouagan reservoir by merging two crescent-shaped lakes: Mouchalagane Lake on the western side and Manicouagan Lake on the eastern side. Covering an area of 2,020 km² (780 sq mi), René-Levasseur Island is considered to be the second largest island in the world located in a lake, in terms of area (the largest is Manitoulin Island in Lake Huron).^[24]

The island was named after René Levasseur, the chief engineer responsible for the construction of the Daniel-Johnson dam. Levasseur died at the age of 35, only days before the dam's inauguration.

Powerhouses

The Daniel Johnson Dam fuels two powerhouses, the Manic-5 and Manic-5-PA. The first powerhouse consists of eight Francis turbines, capable of producing up to 1,528 MW of power, which went online in 1970. The second powerhouse, the Manic-5-PA (PA stands for puissance additionnelle or additional power), was commissioned in 1989, and consists of four Francis turbines of 1,064 MW in total installed capacity.

The designers of the Manic-5 decided on an above ground power house that was downstream of the dam for safety and cost. The intake was built on the east side of the dam and supplies two 3,400 ft (1,000 m), long 36 ft (11 m) diameter concrete-lined penstocks (tunnels). Just before reaching the power house and its eight turbines, each penstock splits into four branches. The power house is about 2,500 ft (760 m) downstream of the dam and utilizes two surge tanks for sudden rises in water pressure from the two penstocks. Each surge tank has a 80 ft (24 m) diameter expansion chamber and is about 40 ft (12 m) higher than the actual dam structure. The surge tanks protect the penstocks and turbines from water hammer which would occur if the turbine gates were quickly closed and water pressure suddenly increases.

Daniel-Johnson Dam Barrage Daniel-Johnson
Locale	Quebec, Canada
Coordinates	50°38′48″N 68°43′28″W / 50.64667°N 68.72444°W / 50.64667; -68.72444Coordinates: 50°38′48″N 68°43′28″W / 50.64667°N 68.72444°W / 50.64667; -68.72444
Construction began	1959
Opening date	1970
Owner(s)	Hydro-Québec
Dam
Type of dam	Concrete, multiple-arch buttress
Length	1,314 m (4,311 ft)
Height	214 m (702 ft)
Crest width	3 m (10 ft)
Base width	22.5 m (74 ft)
Volume	2,200,000 m3 (2,880,000 cu yd)
Impounds	Manicouagan River
Type of spillway	Service, gate-controlled
Reservoir
Creates	Manicouagan Reservoir
Capacity	142,000,000,000 m3 (5.0×1012 cu ft)
Catchment area	29,241 km (18,170 mi)
Surface area	1,950 km2 (753 sq mi)
Power station
Owner(s)	Hydro-Québec
Commission date	1970-71 (Manic-5) 1989-90 (Manic-5-PA)
Turbines	8 (Manic-5) 4 (Manic-5-PA)
Installed capacity	1,592 MW (Manic-5) 1,064 MW (Manic-5-PA)

The W. A. C. Bennett Dam is a large hydroelectric power plant earthfill dam on the Peace River in northern British Columbia, Canada. The W. A. C. Bennett Dam, located 19 kilometres (12 mi) west of Hudson's Hope, and 85 kilometres (53 mi) northwest of Chetwynd, is named after the late former premier W. A. C. Bennett, and came on-line in 1968. During the planning and construction phase it was called the "Portage Mountain Development."

The complex consists of the main earth-fill dam, which holds back Williston Lake, and the underground Gordon M. Shrum Generating Station. It is capable of generating 2,730 megawatts of electricity at peak capacity. The W. A. C. Bennett Dam is constructed 660 m (2,170 ft) above sea level.

The W.A.C. Bennett Dam Visitor Centre is located at the dam, overlooking Williston Lake Reservoir. The centre features exhibits on the dam, hydroelectricity, and the area's natural and cultural history. There is also a video theatre and a cafe. The dam is also very close to the Peace River dam, a few miles south.

Under the direction of Dal Grauer. B.C. Electric obtained the necessary permits and land titles to proceed with the project, completed the design and made preparations for work to begin on site in 1963. However, the assets of that private electric utility company were expropriated by the Provincial Government just as construction of the Peace River hydroelectric dam was about to commence. Several of the top executives of B.C. Electric left the newly created Crown Corporation, B.C. Hydro, and construction proceeded under new management.

The finished project was brought online in the late 1960s and has provided British Columbia, and in particular the Lower Mainland and the City of Vancouver and export markets in the United States, with electricity ever since. The reservoir, once filled, flooded the Finlay, Parsnip, and Peace River valleys and became the largest man made lake on the planet. This flooding was not without consequence, however, to the people who had been living in those valleys.

At the time, the Peace River project was one of the largest developments of its kind in the world. It provided thousands of jobs during construction and facilitated rapid industrial growth throughout British Columbia over the next forty years.

W. A. C. Bennett Dam
Locale	British Columbia, Canada
Coordinates	56°01′00″N 122°12′02″W / 56.0166667°N 122.20056°W / 56.0166667; -122.20056Coordinates: 56°01′00″N 122°12′02″W / 56.0166667°N 122.20056°W / 56.0166667; -122.20056
Construction began	1963
Opening date	1968
Owner(s)	BC Hydro
Dam
Type of dam	Embankment dam
Length	2,068 m (6,785 ft)
Height	186 m (610 ft)
Impounds	Peace River
Reservoir
Creates	Williston Lake
Capacity	7,400,000,000 m3 (2.6×1011 cu ft)
Surface area	1,761 km2 (680 sq mi)
Power station
Turbines	10 × 273 MW
Installed capacity	2,730 MW
Annual generation	13,100 GWh

The La Grande-4 generating station is a hydroelectric power plant on the La Grande River that is part of Hydro-Québec's James Bay Project. The La Grande-4 generating station can generate 2,779 MW and was commissioned in 1984–1986. It generates electricity through the reservoir and dam system.

La Grande-4 Generating Station
Official name	La Grande-4
Locale	Quebec, Canada
Coordinates	53°53′10″N 73°27′45″W / 53.88611°N 73.4625°W / 53.88611; -73.4625Coordinates: 53°53′10″N 73°27′45″W / 53.88611°N 73.4625°W / 53.88611; -73.4625
Opening date	1986
Owner(s)	Hydro-Québec
Dam
Impounds	La Grande River
Discharge capacity of spillway	7,335 m3/s (259,033 cu ft/s)
Reservoir
Creates	LG-4 Reservoir
Surface area	765 km2 (295 sq mi)
Power station
Turbines	9 × 308.8 MW (Francis turbine)
Head	116.7 m (383 ft)
Installed capacity	2,779 MW

Since 1970, the waters of the Churchill River have been diverted into the nearby Churchill Falls hydroelectric power plant. 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 (5,428 MW (7,279,000 hp) installed, expandable to about 6,300 MW (8,400,000 hp)) and is also the second largest underground power station in the world, after the Robert-Bourassa generating station in northern Quebec.

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 1,000 ft (300 m) 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 5,428 MW (7,279,000 hp). 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 mi) in length. At the time, the project was the largest civil engineering project ever undertaken in North America.

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 sq mi (5,700 km²) and provides storage area for more than 1,000,000,000,000 cubic feet (2.8×10¹⁰ 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 sq mi (60,000 km²). Once Orma and Sail lakes' outlets were diked, it added another 4,400 sq mi (11,000 km²) of drainage for a total of 27,700 sq mi (72,000 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 cu mi (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 by the Churchill Falls (Labrador) Corporation Ltd. — whose shareholders are Nalcor (65.8%) and Hydro-Québec (34.2%) and operated by the Newfoundland and Labrador Hydro company.

The government of Quebec considered the inland watershed of Labrador to be part of their province and fought a long but losing legal battle to prevent granting the territory to Newfoundland at the Judicial Committee of the Privy Council.

The Churchill Falls hydroelectric power plant development was undertaken in the absence of any agreement with the aboriginal Innu people of Labrador. The construction involved the flooding of over 5,000 km² (1,900 sq mi) of traditional hunting and trapping lands. A recent agreement signed between the government of Newfoundland and Labrador and the Innu offered the Labrador Innu hunting rights within 34,000 square kilometres of land, plus $2 million annually in compensation for flooding.

Project facts of Churchill Falls Power Plant

• Churchill Falls power plant is the second largest hydroelectric plant in North America, with an installed capacity of 5,428 MW (7,279,000 hp).
• 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 (296 m) long, up to 81 ft (25 m) wide and 154 ft (47 m) high from the bottom to the top. The height would be equivalent to a 15-storey building or almost as long as three Canadian football fields (990 ft (300 m) 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 2,300,000 cu yd (1,760,000 m³) of rock that was excavated from the underground caverns, it required 5,000,000 lb (2,300,000 kg). 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 (73 t) which is a world record for the largest stainless steel casting ever made.
• During construction, 730,000 short tons (660,000 t) of material, equipment and fuel were moved to the site.
• The natural catchment area for the Churchill River covers over 23,300 sq mi (60,000 km²).
• By diverting the water from the Ossokmanuan Reservoir the total catchment area became 27,700 sq mi (72,000 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 (19 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 mi) and the highest is 36 m (118 ft). The total length of all dikes is 64 km (40 mi) and contains 26,000,000 cu yd (20,000,000 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 (2,700,000 hp) dam at Gull Island, an 824 MW (1,105,000 hp) dam at Muskrat Falls, 1,000 MW (1,300,000 hp) 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 (5,400,000 hp) for a total of 9,252 MW (12,407,000 hp) for the entire Churchill River hydroelectric complex.

Churchill Falls Hydroelectric Power Plant Spesification

Churchill Falls generating station
Year commissioned:	1971
Installed capacity:	5,428 MW (7,279,000 hp)
Annual energy output:	35,000 GWh (130,000 TJ)
Number of turbines:	11
Turbine capacity:	493.5 MW (661,800 hp)
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 (1,025 ft)
Maximum tailrace discharge:	49,000 ft³/s (1,390 m³/s)
Powerhouse:	296 m (971 ft) length, 25 m (82 ft) width, 47 m (154 ft) height, 310 m (1,020 ft) below ground
Tailrace tunnels:	2 × 1,691 m (5,548 ft), 14 m (46 ft) width, 19 m (62 ft) height
Penstocks:	11 × 427 m (1,401 ft) length, 20 ft (6.1 m) diameter
Cable shafts:	11 × 7 ft (2.13 m) diameter, 263 m (863 ft) deep
Dikes:	88; 64.4 km (40.0 mi) total length, 9 m (30 ft) average height, 36 m (118 ft) maximum height
Size of reservoir:	6,988 km2 (2,698 sq mi)
Total catchment area:	71,700 km2 (27,700 sq mi)