The Great Lakes are a group of five large lakes on or near the United States-Canadian border. They are the largest group of freshwater lakes in the world, and the Great Lakes-St. Lawrence system is the largest fresh-water system in the world.
The Great Lakes are (west to east, general direction of water flow):
Four of these lakes straddle the US-Canada border; the fifth, Lake Michigan, is entirely within the United States. The Saint Lawrence River, which marks the same international border for portions of its course, is a primary outlet of these interconnected lakes, and flows through Quebec and past the Gaspé Peninsula to the northern Atlantic Ocean.
The lakes are heavily used for transportation, though cargo traffic has decreased considerably in recent years. Storms and reefs are a common threat, and many ships have sunk in these waters. The Edmund Fitzgerald was the last major freighter lost on the lakes. The Great Lakes Waterway makes each of the lakes accessible.
The Saint Lawrence Seaway and Great Lakes Waterway opened the Great Lakes to ocean-going vessels. However the move to wider ocean-going container ships which do not fit through the locks has limited commerce.
The Great Lakes were formed at the end of the last ice age, about 10,000 years ago, when the Laurentide Glaciation receded. When this happened, the giant glacier scratched a deep hole within the Earth's surface. The melting also left behind a large amount of meltwater (see Lake Agassiz) which filled up these holes, which were soon to become the Great Lakes. Because of the uneven nature of glacier erosion, some higher hills became Great Lakes islands.
In 2002, 162 million net tons of dry bulk cargo was moved on the Lakes. This was, in order of volume, iron ore, coal, stone, grain, salt, cement and potash. The iron ore and much of the stone and coal are used in the steel industry. There is also some shipping of liquid and containerized cargo. The total amount of shipping on the lakes has been on a downward trend for several years.
Recreational boating and tourism are major industries on the Great Lakes. A few small cruise ships operate on the Great Lakes including a couple of sailing ships. Sport fishing, commercial fishing and Native American fishing represents a 4 billion dollar (US) a year industry with salmon, whitefish, smelt, lake trout, and walleye being major catches.
The Great Lakes are used to supply drinking water to tens of millions of people in bordering areas.
Several ferries operate on the Great Lakes to carry passengers to various islands, including Isle Royale, Pelee Island, Mackinac Island, Beaver Island, both Bois Blanc Islands, Kellys Island, South Bass Island, North Manitou Island, South Manitou Island, Harsens Island, Manitoulin Island, and the Toronto Islands. Only one car ferry crosses the Great Lakes, carrying passengers across Lake Michigan from Ludington, Michigan to Manitowoc, Wisconsin. A new ferry service is scheduled to start in the spring of 2004 between Toronto and Rochester, New York.
To be written:
Lake Champlain briefly became the sixth "Great Lake of the United States" on March 6, 1998, when President Clinton signed Senate Bill 927. This bill, which reauthorized the Sea Grant Program, contained a line penned by Senator Patrick Leahy (D-VT) declaring Lake Champlain to be a Great Lake. Not coincidentally, this status allows neighboring states to apply for additional federal research and education funds allocated to these national resources. Following a small uproar (and several New York Times articles), the Great Lake status was rescinded (although Vermont universities continue to receive funds to monitor and study the lake.)
This term can also be used to identify of a number of lakes throughout the world, and the region around them. Most important, in East Africa, the Great Lakes Region is the area around Lake Victoria, Lake Tanganyika, Nyasa Lake, and Lake Albert.
There is also the place Great Lakes, New South Wales in Australia.Geologic Pre-History
Modern Economy of the Lakes
The Great Lakes are used as a major mode of transportation for bulk goods. The brigantine Le Griffon, which was commissioned by René Robert Cavelier, Sieur de La Salle, was towed to the southern end of the Niagara River, to become the first ship to sail the upper Great Lakes on August 7, 1679.