Caniapiscau Reservoir

Caniapiscau Reservoir
Caniapiscau Reservoir Location in Quebec
Location	Caniapiscau / Baie-James, Quebec, Canada
Coordinates	54°09′27″N 69°50′44″W / 54.15750°N 69.84556°W / 54.15750; -69.84556Coordinates: 54°09′27″N 69°50′44″W / 54.15750°N 69.84556°W / 54.15750; -69.84556
Type	Artificial
Primary inflows	Caniapiscau River
Primary outflows	Laforge River, Caniapiscau River
Catchment area	36,800 km2 (14,200 sq mi)
Basin countries	Canada
Max. length	120 km (75 mi)
Max. width	135 km (84 mi)
Surface area	4,318 km2 (1,667 sq mi)
Max. depth	49 m (161 ft)
Water volume	53.8 km3 (12.9 cu mi)
Residence time	2.2 years
Shore length1	4,850 km (3,010 mi)
Surface elevation	535 m (1,755 ft)
Islands	300
Settlements	Caniapiscau
1 Shore length is not a well-defined measure.

The Caniapiscau Reservoir (in French, Réservoir de Caniapiscau) is a reservoir on the upper Caniapiscau River in the Côte-Nord administrative region of the Canadian province of Quebec. It is the largest body of water in Quebec and the second largest reservoir in Canada.

The Caniapiscau Reservoir, formed by two dams and forty-three dikes, is the largest reservoir in surface area of the James Bay Project. As headpond, it feeds the power plants of the La Grande complex in the winter and provides up to 35% of their production. Its total catchment area is about 36,800 square kilometres (14,200 sq mi).

The reservoir was named after Lake Caniapiscau that was flooded during the formation of the reservoir. The name is an adaptation of the Cree or Innu toponym kâ-neyâpiskâw, which means "rocky point". Albert Peter Low had noted in 1895 that "a high rocky headland jutts into the lake." He probably referred to the northwest facing peninsula that gives the reservoir the shape of an arc as we current know it.

The Caniapiscau Reservoir is accessible by bush plane and, since 1981, by a gravel road from James Bay (the Trans-Taiga Road). At the very end of this road, near the Duplanter spillway, is the former worksite of the Société d'énergie de la Baie-James, named Caniapiscau. There is no permanent human habitation at the reservoir, but it is used by outfitters for seasonal hunting and fishing expeditions and by some Cree for subsistence fishing and trapping. It is isolated from society and there are very few gas stations or other services nearby.

The natural lakes of the region were formed about nine thousand years ago as glaciers left Quebec after having scoured the Canadian Shield for ninety thousand years. The prototype of these lakes was an ice dam lake that drained southwards into the Gulf of Saint Lawrence at a time when areas further north (Nunavik) were still glaciated. As post-glacial rebound elevated the southern part of the Canadian Shield more rapidly than the north, the region began to drain northward into the Caniapiscau River, a tributary of the Koksoak River, and ultimately into Ungava Bay.