Menihek Hydroelectric Generating Station

Menihek Hydroelectric Generating Station
Location of Menihek Hydroelectric Generating Station
Country	Canada
Location	Newfoundland and Labrador
Coordinates	54°28′16″N 66°36′45″W / 54.47111°N 66.6125°W / 54.47111; -66.6125Coordinates: 54°28′16″N 66°36′45″W / 54.47111°N 66.6125°W / 54.47111; -66.6125
Status	Operational
Construction began	1951
Opening date	1954
Owner(s)	Newfoundland and Labrador Hydro
Dam and spillways
Type of dam	Barrage dam
Length	228.6 m (750 ft)
Crest width	6 m (20 ft)
Crest elevation	451.10 m (1,480 ft)
Impounds	Ashuanipi River
Spillway capacity	4,247 m3/s (150,000 cu ft/s)
Reservoir
Creates	Lake Menihek
Active capacity	423.8 hm³ (1.5×1010 cu ft)
Catchment area	19,166 km2 (7,400 sq mi)
Normal elevation	449.59 m (1,475 ft)
Power station
Type	Run-of-the-river
Hydraulic head	10.4 m (34 ft) (units 1-2) 12 m (40 ft) (unit 3)
Turbines	2 fixed-blade propeller-type 1 Kaplan turbine
Installed capacity	17.2 MW
Maximum capacity	18.7 MW 2 × 4,400 kW (1954); 1 × 9,900 kW (1960)
Capacity factor	26%
Annual generation	40 GWh
As of July 2011
Sources: RSW Inc. 2001, pp. 24–25; Cloutier et al. 2002, p. 30

The Menihek Hydroelectric Generating Station is a conventional hydroelectric generating station at Menihek Lake in Labrador. The dam and powerhouse are located in the Canadian province of Newfoundland and Labrador, 40 km (25 mi) south of the isolated town of Schefferville, Quebec and two First Nations communities: Matimekosh—Lac-John and Kawawachikamach. The generating station, two 69 kV power lines and the distribution networks in each community are forming an independent electricity network, off the main North American grid.

Geography

The power development is located approximately 600 km (370 mi) north of Sept-Îles, Quebec,^[1] in a unhabitated region in the northwestern tip of Labrador, just south of the Laurentian Divide between the Atlantic and Arctic drainage basins which delineates the Quebec–Newfoundland and Labrador border in the area. The climate in Schefferville, Quebec, straddling the demarcation 40 km (25 mi) north of Menihek, is characterized by an average temperature of −5.3 °C (22.5 °F) — which can drop as low as −51 °C (−60 °F) in the winter and rise to 34 °C (93 °F) in the summer. The average frost-free period lasts from mid-June to mid-September. The area receives on average 833 mm (32.8 in) of precipitations, roughly divided between solid and liquid.^[2]

The terrain in this remote area is rugged and the dam is only accessible by a narrow dirt road from Schefferville. In a 2002 audit, an Hydro-Québec team described it as in need of urgent repairs.^[3]

History

The facilities were built between 1951 and 1954 by the Iron Ore Company of Canada to meet the power requirements of its iron ore mining operations at the Knob Lake site, near the company town of Schefferville. After IOC closed the mine in 1982, it kept the generating station running for two decades. However, in the early 2000s, the mining company gave notice to the Government of Quebec that it would cease to operate the plant and electric network as of November 1, 2002. In a last-minute deal, Hydro-Québec agreed to pay for all charges incurred by IOC to run the money-losing network while the governments of Quebec and Newfoundland and Labrador and the Native communities tried to reach a deal on a mutually acceptable way to split the assets.^[4]

A milestone was reached by the two provinces and their respective utilities on December 14, 2005.^[5] IOC would sell all interests in the generating station and part of the transmission lines to provincially owned Newfoundland and Labrador Hydro (NLH), as is, for $1, while transferring its Quebec utility operations to Hydro-Québec for the same amount. Under the deal, the generating station would be operated by NLH employees, but it would be managed by a 4-person operating committee staffed by personnel of both utilities.^[6]

Under the 40-year contract,^[7] Hydro-Québec is responsible for any operation, maintenance and refurbishment costs of the network's facilities owned by NLH and agrees to buy a firm volume of 40 GWh/year at 3¢/kWh with the remainder at 2¢. Rates are ajusted to the consumer price index for the duration and NLH has the right to recall power and break the contract with a 6-year notice.^[6] The agreement was finalized on November 15, 2007.^[8]

Dam and powerhouse

The power development at the Menihek site includes a 228.6 m (750 ft) concrete gravity dam, a water intake, the powerhouse and a 4-gate spillway, with a capacity of 4,247 m³/s (150,000 cu ft/s).^[9]

The impoundment of Menihek Lake, which serves as a reservoir, is completed by three rock-fill dikes made of glacial till, for a total length of 6.2 km (4 mi). The Tshiuetin Rail Transportation shortline railway (formerly the Menihek Subdivision of the Quebec North Shore and Labrador Railway) connecting Schefferville and Sept-Îles uses the dikes to cross the area.^[10]

The powerhouse was designed to receive four generating units but only two were installed when the plant came on stream in 1954. Units 1 and 2 are equipped with fixed-blade propeller-types turbines and each have a capacity of 4,400 kW at a nominal hydraulic head of10.4 m (34 ft). Each turbine is coupled to a 5,000 kVA alternator. In 1960, IOC added unit 3, a 9,900-kW Kaplan turbine under a 12 m (39 ft) head and its 12,000 kVA alternator.^[9]

2005 failure of unit 3

Notes and references

1. ^ Hydro-Québec Distribution 2006, p. 6.
2. ^ Envir-Eau 2009, p. 9
3. ^ Cloutier et al. 2002, p. 27-29.
4. ^ Hydro-Québec Distribution 2006, p. 10-11.
5. ^ Hydro-Québec Distribution 2006, p. 12.
6. ^ ^{a b} Hydro-Québec Distribution 2006, p. 18-20.
7. ^ Newfoundland and Labrador Hydro; Hydro-Québec (December 14, 2005). "Agreement for the purchase and sale of electricity". Régie de l'énergie du Québec. http://www.regie-energie.qc.ca/audiences/3602-06/Requete3602/B-1_HQD-1Doc1_3602_12mai06.pdf. Retrieved July 8, 2011. 
8. ^ "Newfoundland and Labrador Hydro, Hydro-Québec and Iron Ore Company of Canada reach an agreement to supply electricity to three northern Québec communities" (Press release). Newfoundland and Labrador Hydro. November 15, 2007. http://www.nlh.nl.ca/HydroWeb/NLHydroWeb.nsf/DisplayArchivedNews/EB1E2DAC905C5101A325754D0058A4F4?OpenDocument. Retrieved July 7, 2011. 
9. ^ ^{a b} RSW Inc. 2001, p. 24.
10. ^ Cloutier et al 2002, p. 26.

Works cited

• Cloutier, J.; Gagnon, J.; Labrèche, M.; Nguyen, P.; Ouellet, R.; Pleau, Y. (October 2002) (in French). Audit de la centrale Menihek. Montreal: Hydro-Québec Production. http://www.regie-energie.qc.ca/audiences/3602-06/DDR3602/RepDDR3602/B-7_HQD-3Doc1-2-Annexe2_3602_07juil06.pdf. Retrieved July 7, 2011. 
• Envir-Eau (March 2009). Hydrogeological report DSO2 and DSO3 sectors. Schefferville (Quebec) and Elross Lake (Newfoundland and Labrador). Gatineau, Quebec: Newfoundland and Labrador Department of Environment and Conservation. http://www.env.gov.nl.ca/env/env_assessment/projects/Y2010/1380/supporting_studies_e_g.pdf. Retrieved July 8, 2009. 
• Hydro-Québec Distribution (May 31, 2006). Projet de prise en charge de l'alimentation électrique de la région de Schefferville, phase I. Montreal: Régie de l'énergie du Québec. Docket R-3602-2006. http://www.regie-energie.qc.ca/audiences/3602-06/Requete3602/B-3-HQD-02-01_Revise_3602_31mai06.pdf. Retrieved July 8, 2011. 
• RSW Inc. (November 2001) (in French). Étude sur la centrale de Menihek et ses réseaux de transport et de distribution. Rapport préliminaire, volet 1. Montreal: RSW Inc. http://www.regie-energie.qc.ca/audiences/3602-06/DDR3602/RepDDR3602/B-7_HQD-3Doc1-Annexe2_3602_07juil06.pdf. Retrieved July 8, 2011. 

See also

• List of electrical generating stations in Newfoundland and Labrador
• Churchill Falls Generating Station
• Labrador boundary dispute
• History of Hydro-Québec