Lake Winnipeg

Infobox_lake
lake_name = Lake Winnipeg
image_lake = Gimli harbour.jpg
caption_lake = Gimli, Manitoba's harbour
image_bathymetry = Lake Winnipeg map.pngcaption_bathymetry = Map
location = Manitoba, Canada
coords = coord|52|7|N|97|15|W|type:waterbody_region:CA|display=inline,title
type = Formerly part of the Glacial Lake Agassiz, reservoir
inflow = Winnipeg River, Saskatchewan River, "precipitation", Red River
outflow = Nelson River
catchment = convert|984200|km2|sqmi|abbr=on
basin_countries = Canada, United States
length = convert|416|km|mi|abbr=on
width = convert|100|km|mi|-1|abbr=on (N Basin)
convert|40|km|mi|-1|abbr=on (S Basin)
area = convert|24514|km2|sqmi|0|abbr=on
depth = convert|12|m|ft|abbr=on
max-depth = convert|36|m|ft|abbr=on
volume =
residence_time = 3.5 years
shore = convert|1858|km|mi|abbr=on
elevation = convert|217|m|ft|0|abbr=on
islands =
cities = Gimli, Manitoba
frozen =

Lake Winnipeg is a very large (km2 to sq mi|24514|abbr=on|precision=0) lake in central North America, in the province of Manitoba, Canada, about km to mi|55|spell=UK north of the city of Winnipeg. It is the largest lake within the borders of southern Canada, and it is part of the most undeveloped and pristine large watershed of southern Canada.

It is the fifth-largest freshwater lake in Canada, [ [http://www.greatcanadianlakes.com/gc_lakes/Canada/index.htm Great Canadian Lakes ] ] but it is relatively shallow (mean depth of convert|12|m|ft|0|abbr=on [ [http://www.ilec.or.jp/database/nam/nam-08.html nam-08 ] ] excluding a narrow convert|36|m|ft|0|abbr=on deep channel between the northern and southern basins. It is the eleventh-largest freshwater lake on Earth. The east side of the lake has pristine boreal forests and rivers that are being promoted as a potential United Nations World Heritage Park. The lake is elongated in shape, and is km to mi|416|spell=UK km from north to south, with remote sandy beaches, large limestone cliffs, and many bat caves in some areas. Manitoba Hydro uses the lake as one of the largest reservoirs in the world. There are many islands in the lake, and most of them are undeveloped and pristine.

The lake's watershed measures about km2 to sq mi|984200|spell=UK, and covers much of Alberta, Saskatchewan, Manitoba, northwestern Ontario, Minnesota, and North Dakota. Some of its tributaries include:

*the Saskatchewan River (through Cedar Lake),
*the Red River (draining the Assiniboine River),
*the Winnipeg River (draining Lake of the Woods, Rainy River and Rainy Lake); and
*Lake Manitoba (draining Lake Winnipegosis),
*Bloodvein River (on the East side, draining from the Canadian Shield)
*Poplar River
*Manigatogan River

Lake Winnipeg drains northward into the Nelson River at an average annual rate of 2,066 cubic metres per second (72,960 cu ft/s), and forms part of the Hudson Bay watershed, which is one of the largest in the world. This watershed area was historically known as Rupert's Land when the Hudson's Bay Company formed in 1670.

Lakes Winnipeg, Manitoba, and Winnipegosis are found at the floor of the prehistoric Glacial Lake Agassiz. The area between Lake Winnipeg and Lakes Winnipegosis and Manitoba is called the Interlake Region, and the whole region is called the Manitoba Lowlands.

The first European to have seen the lake is believed to have been Henry Kelsey in 1690. He adopted the Cree language name for the lake: "wīnipēk" (ᐐᓂᐯᐠ), meaning "muddy waters". La Verendrye referred to the lake as "Ouinipigon" when he built the first forts in the area in the 1730s. Later, the Red River Colony to its south would take the lake's name and become Winnipeg, the capital of Manitoba.

Due to its long, narrow shape, the lake exhibits a variety of interesting wind and wave effects, including waves of up to one metre in height at its southern shore, a process called wind tide. This occurs when prevailing northerly winds blow along the length of Lake Winnipeg, exerting a horizontal stress on its surface. Surface waters move in the direction of the wind and pile up along the windward south shores.

Furthermore, water depths are known to be extremely variable at the south end of the lake. Many of the recreational beaches on the southern end of the lake feature rustic, seasonal piers for swimmers. It is not uncommon to be able to walk off the end of one of these piers one day into more than waist-deep water, then return a few days later to the same spot to find the water only ankle deep, or even exposed sand.

Setups greater than 1 m above normal lake levels have been recorded along many of southern Lake Winnipeg's recreational beaches, and the associated high waves with their uprush effects have caused considerable storm damage, backshore flood and shoreline erosion. The highest setups occur in the fall, when the northerly winds are strongest. If the winds die down suddenly, the waters rush northward, then slosh back and forth in a process called seiching.

Communities on the lake include Grand Beach, Riverton, Gimli, Winnipeg Beach, Victoria Beach, Pine Falls, Manigotagan, Berens River, Bloodvein, and Grand Rapids. A number of pleasure beaches are found on the southern end of the lake.

Fishing

Lake Winnipeg serves important commercial fisheries. It is one of the main lakes in Manitoba's 30 million dollar annual commercial catch. [http://www.gov.mb.ca/conservation/fish/] a shipping route, and the southern shore is a popular summer resort area.

Lake as a transportation route

Due to its length the Lake Winnipeg water system and the lake itself was an important transportation route in the province before the railways reached Manitoba, and it continued to serve as a notable transportation route even after the railways had established a foothold in the province. In addition to Indian canoes and York Boats there were several steamboats that plied the lake, including "Anson Northup", "City of Selkirk", "Colvile", "Keenora", "Premier", "Princess", "Winnitoba" and "Wolverine".

References

* [http://www.thecanadianencyclopedia.com/index.cfm?PgNm=TCE&Params=A1ARTA0008645 The Canadian Encyclopedia (some facts & figures in this article)]
* [http://www.lakewinnipegresearch.org Lake Winnipeg Research Consortium - a detailed site dedicated to the lake]
* [http://www.gov.mb.ca/waterstewardship/water_quality/lake_winnipeg/index.html Manitoba Water Stewardship - a site run by the Government of Manitoba]