Lake Manitoba

Lake Manitoba
Location	Manitoba
Coordinates	51°00′N 98°50′W / 51°N 98.833°W / 51; -98.833Coordinates: 51°00′N 98°50′W / 51°N 98.833°W / 51; -98.833
Primary  inflows	Waterhen River Mossy River Whitemud River
Primary  outflows	Dauphin River
Catchment  area	54,630 km2 (21,093 sq mi)
Basin  countries	Canada
Max. length	200 km (125 mi)
Max. width	45 km (28 mi)
Surface area	4,624 km2 (1,785 sq mi)
Max. depth	7 m (23 ft)
Water volume	14.1 km3 (3.4 cu mi)
Surface  elevation	812 ft (247 m)
Settlements	Fairford, Steep Rock, St. Laurent, Sandy Bay

Lake Manitoba is Canada's thirteenth largest lake (4,624 km²) and the world's 33rd largest freshwater lake. It is in central North America, in the Canadian province of Manitoba, which the lake is named after. It is located about 75 km northwest of the province's capital, Winnipeg, at 51°0′N 98°45′W / 51°N 98.75°W / 51; -98.75.

History

The lake, its shores populated by the Assiniboine and Cree, was made known to Europeans by La Vérendrye in the mid-1730s. He and his sons travelled from Fort La Reine through this lake to explore the Saskatchewan River and its environs. Forts were established on both the Saskatchewan and Cedar Lake. It also was part of the route of the fur trade to Hudson Bay.

The name derives from Cree manitou-wapow or Ojibwa manitou-bah, both meaning "straits of Manitou, the Great Spirit", a toponym referring to what are now called The Narrows in the centre of the lake. The lake was known to French explorers as Lac des Prairies.

Manipogo

For many years there have been claims that a monster similar to Scotland's Loch Ness Monster and British Columbia's Ogopogo lives in the lake. It has been named Manipogo. Sightings of this serpent like sea monster have been going on since roughly 1908.

Geography

The irregularly shaped lake, about 200 km long, is the smallest of a group of three large lakes, the other two being Lake Winnipeg (the largest) and Lake Winnipegosis, which are found on the floor of the prehistoric Glacial Lake Agassiz. The lake is subdivided into two connected but distinctly different basins: a small, irregular-shaped north basin and a much larger south basin. It is part of the watershed of the Nelson River and Hudson Bay.

The southern tip of the lake, 24 km north of Portage la Prairie, Manitoba, ends in the Delta Marsh, an important staging ground for migrating birds.

Communities on the lake include Fairford, Steep Rock, St. Laurent, and Sandy Bay.

River basins

The lake is primarily fed by Lake Winnipegosis to its northwest via the Waterhen River, with an average annual contribution of 1.9 million acre feet (2.4 km³). The Whitemud River and local overland flow average about 257,000 acre feet (0.32 km³). Precipitation contributes about 1.8 million acre feet (2.2 km³). From 1970 to 2003 the Portage Diversion has contributed an average annual volume of 246800 acre feet (0.31 km³) from the Assiniboine River. Lake Manitoba drains northeast into Lake Winnipeg via the Dauphin River. The average annual river outflow is 2.03 million acre feet (2.5 km³). Average evaporation is 2.02 million acre feet (2.55 km³) per year. Most of the water inflow is from the Waterhen River (42% of the inflow) and from precipitation directly on the lake's surface (40%), while nearly 50% of the outflow is by evaporation.^[1]

Fishing

Lake Manitoba is one of the three main lakes in Manitoba's $30-million annual commercial fishing industry.^[2]

The main marketable fish species caught on Lake Manitoba has changed from whitefish in the late 1800s to walleye, sauger and yellow perch today. There has been a large increase in rough fish like carp and mullet. Tulibee catch remains high, although it is not considered a commercial species.

The total recorded catch of the commercial winter fishery on the lake has declined from 15 million pounds (6.8 kt) annually in the late 1940s to less than 4.5 million pounds (2.0 kt) in 2002.

Regulation

Severe flooding around the lake led to the excavation of an improved outlet channel between 1899 and 1901. In 1933 following dry years in the late 1920s and early 1930s, the Province constructed a concrete control dam across the Fairford River immediately downstream of the channel. A new dam was constructed in 1961. The new structure is operated to try to control levels between 810.5 and 812.5.

References

External links

• Modern sedimentology and hydrology of Lake Manitoba