The Niagara Falls - among the largest, most impressive and best known falls in the world - lie in the extreme nor
th-west of New York State. Here masses of water from Lake Erie plunge over an almost 200 ft drop to flow into Lake Ontario. First described and sketched by a missionary, Louis Hennepin in 1678, they attract over 12 million visitors a year.
The masses of water are used to produce energy. The present hydroelectric power stations have a total output of 3 million kW. Before the falls were harnessed to produce electricity, water poured down at the rate of almost 1,300,000 gallons per second. A Canadian-American agreement of 1951 on the joint use of the water guarantees a daytime flow of just under half that amount during the summer and just under a quarter at night and in the winter.
Formation The origins of the Niagara Falls go back to the Ice Age, when the river, flowing at a higher level than today over a limestone plateau on the Niagara escarpment, dropped down to the level of Lake Ontario near the present-day town of Lewiston. Then, as a result of retrograde erosion, the falls rapidly moved upstream. Over the last 3000 years they have moved back from the Rainbow Bridge to their present position. The pace of erosion depends on the volume of water going over the falls; but at present rates it can be expected that within a few hundred thousand years the Niagara Falls will be close to the American city of Buffalo.
eography The masses of water from Lake Erie thunder over a horseshoe-shape rock wall 700 yds long at the Horseshoe Falls, which are in Canada, and, a short distance north-east, over the straight American Falls, 360 yds long. The frontier between the United States and Canada runs along the middle of the river.
th-west of New York State. Here masses of water from Lake Erie plunge over an almost 200 ft drop to flow into Lake Ontario. First described and sketched by a missionary, Louis Hennepin in 1678, they attract over 12 million visitors a year.The masses of water are used to produce energy. The present hydroelectric power stations have a total output of 3 million kW. Before the falls were harnessed to produce electricity, water poured down at the rate of almost 1,300,000 gallons per second. A Canadian-American agreement of 1951 on the joint use of the water guarantees a daytime flow of just under half that amount during the summer and just under a quarter at night and in the winter.
Formation The origins of the Niagara Falls go back to the Ice Age, when the river, flowing at a higher level than today over a limestone plateau on the Niagara escarpment, dropped down to the level of Lake Ontario near the present-day town of Lewiston. Then, as a result of retrograde erosion, the falls rapidly moved upstream. Over the last 3000 years they have moved back from the Rainbow Bridge to their present position. The pace of erosion depends on the volume of water going over the falls; but at present rates it can be expected that within a few hundred thousand years the Niagara Falls will be close to the American city of Buffalo.
eography The masses of water from Lake Erie thunder over a horseshoe-shape rock wall 700 yds long at the Horseshoe Falls, which are in Canada, and, a short distance north-east, over the straight American Falls, 360 yds long. The frontier between the United States and Canada runs along the middle of the river.
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