Outardes-4
Encyclopedia
Outardes-4 is a hydroelectric
power station
and dam
on the Outardes River 70 km (43.5 mi) northwest of Baie-Comeau, Quebec
, Canada
. The power station was commissioned in 1969 and is supplied by the Outardes-4 Reservoir which is created by seven additional dams.
was constructed upstream to direct the river into the diversion tunnel but no cofferdam was built downstream because the river's grade was sufficient enough in that area. Once the river was diverted, work commenced on Dam No. 1's foundation. Workers and engineers cleared alluvial material from the riverbed but ran into uplift faults and pot-holes. Around six pot-holes with 10 ft (3 m) to 15 ft (4.6 m) diameters and up to 60 ft (18.3 m) deep had to be excavated, partly by hand. Eventually, those under the dam's foundation were filled in with concrete.
along with Dam No. 2. The six other dams are saddle and auxiliary dams; one is rock and earth-fill, four are earth-fill dikes and one serves as a controlled concrete spillway
. Dam No. 1 is 2087 ft (636.1 m) long and 437 ft (133.2 m) high and made of 9600000 cu yd (7,339,726.6 m³) of material while the second largest dam, No. 2 is 2383 ft (726.3 m) long and 335 ft (102.1 m) high. Dam No. 2 is located 2 km (1.2 mi) north of No. 1 on a side-valley is made of 6100000 cu yd (4,663,784.6 m³) of material. Water from the reservoir helps regulate river flow and power generation at the downstream Outardes-3
and Outardes-2
power stations.
s deliver water from the reservoir to each of the power station's turbines. The power station was commissioned in 1969 and currently has a 785 MW capacity. The power station's turbines were rehabilitated in 2009 which had increased generation capacity by 56 MW.
Hydroelectricity
Hydroelectricity is the term referring to electricity generated by hydropower; the production of electrical power through the use of the gravitational force of falling or flowing water. It is the most widely used form of renewable energy...
power station
Power station
A power station is an industrial facility for the generation of electric energy....
and dam
Dam
A dam is a barrier that impounds water or underground streams. Dams generally serve the primary purpose of retaining water, while other structures such as floodgates or levees are used to manage or prevent water flow into specific land regions. Hydropower and pumped-storage hydroelectricity are...
on the Outardes River 70 km (43.5 mi) northwest of Baie-Comeau, Quebec
Quebec
Quebec or is a province in east-central Canada. It is the only Canadian province with a predominantly French-speaking population and the only one whose sole official language is French at the provincial level....
, Canada
Canada
Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...
. The power station was commissioned in 1969 and is supplied by the Outardes-4 Reservoir which is created by seven additional dams.
Construction
Outardes-4 was built in conjunction with the Manicouagan-Outardes project and is the northern most power station on the Outardes River. Construction on the diversion tunnel for the Outardes River began in September 1964 and was finished in April 1965. A cofferdamCofferdam
A cofferdam is a temporary enclosure built within, or in pairs across, a body of water and constructed to allow the enclosed area to be pumped out, creating a dry work environment for the major work to proceed...
was constructed upstream to direct the river into the diversion tunnel but no cofferdam was built downstream because the river's grade was sufficient enough in that area. Once the river was diverted, work commenced on Dam No. 1's foundation. Workers and engineers cleared alluvial material from the riverbed but ran into uplift faults and pot-holes. Around six pot-holes with 10 ft (3 m) to 15 ft (4.6 m) diameters and up to 60 ft (18.3 m) deep had to be excavated, partly by hand. Eventually, those under the dam's foundation were filled in with concrete.
The dams
The Outardes-4 Reservoir is impounded by eight different dams. The main dam is Dam No. 1 and is a rock-fill, earthen embankment damEmbankment dam
An embankment dam is a massive artificial water barrier. It is typically created by the emplacement and compaction of a complex semi-plastic mound of various compositions of soil, sand, clay and/or rock. It has a semi-permanent waterproof natural covering for its surface, and a dense, waterproof...
along with Dam No. 2. The six other dams are saddle and auxiliary dams; one is rock and earth-fill, four are earth-fill dikes and one serves as a controlled concrete spillway
Spillway
A spillway is a structure used to provide the controlled release of flows from a dam or levee into a downstream area, typically being the river that was dammed. In the UK they may be known as overflow channels. Spillways release floods so that the water does not overtop and damage or even destroy...
. Dam No. 1 is 2087 ft (636.1 m) long and 437 ft (133.2 m) high and made of 9600000 cu yd (7,339,726.6 m³) of material while the second largest dam, No. 2 is 2383 ft (726.3 m) long and 335 ft (102.1 m) high. Dam No. 2 is located 2 km (1.2 mi) north of No. 1 on a side-valley is made of 6100000 cu yd (4,663,784.6 m³) of material. Water from the reservoir helps regulate river flow and power generation at the downstream Outardes-3
Outardes-3
Outardes-3 is a hydroelectric power station and dam on the Outardes River northwest of Baie-Comeau, Quebec, Canada. The power station was commissioned in 1969 and is run-of-the-river....
and Outardes-2
Outardes-2
Outardes-2 is a hydroelectric power station and dam on the Outardes River southwest of Baie-Comeau, Quebec, Canada. The power station was commissioned in 1978 and is run-of-the-river....
power stations.
The power station
The Outardes-4 power station is located on the west bank of the Outardes River, adjacent to Dam No. 1. Four 850 ft (259.1 m) long, 20 ft (6.1 m) wide penstockPenstock
A penstock is a sluice or gate or intake structure that controls water flow, or an enclosed pipe that delivers water to hydraulic turbines and sewerage systems. It is a term that has been inherited from the technology of wooden watermills....
s deliver water from the reservoir to each of the power station's turbines. The power station was commissioned in 1969 and currently has a 785 MW capacity. The power station's turbines were rehabilitated in 2009 which had increased generation capacity by 56 MW.
See also
- Outardes-2Outardes-2Outardes-2 is a hydroelectric power station and dam on the Outardes River southwest of Baie-Comeau, Quebec, Canada. The power station was commissioned in 1978 and is run-of-the-river....
- Outardes-3Outardes-3Outardes-3 is a hydroelectric power station and dam on the Outardes River northwest of Baie-Comeau, Quebec, Canada. The power station was commissioned in 1969 and is run-of-the-river....
- McCormick DamMcCormick DamThe McCormick Dam is a dam and power station built on the Manicouagan river by the Quebec & Ontario Paper Company and the Canadian British Aluminium Company east of Baie-Comeau, Quebec, Canada. It is named after colonel Robert R...
- Jean-Lesage generating station
- René-Lévesque generating station
- Daniel-Johnson DamDaniel-Johnson DamThe Daniel-Johnson Dam , 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 north of Baie-Comeau in Quebec, Canada...
- History of Hydro-QuébecHistory of Hydro-QuébecHydro-Québec is a government-owned public utility established in 1944 by the Government of Quebec. The company is in charge of the generation, transmission and distribution of electricity across Quebec. Its head office is located in Montreal.-Origins:...
- List of hydroelectric stations in Quebec