Niagara
Falls (waterfall),
waterfall in east central North America, located on the Niagara River,
in western New York and southeastern Ontario. Niagara Falls consists of
two cataracts: the Horseshoe, or Canadian, Falls (54 m/176 ft high), on
the Canadian side of the river, and the American Falls (55 m/182 ft
high), on the United States side. The waterfalls are separated by Goat
Island, New York. The crestline of the crescent-shaped Horseshoe
Falls,
which carries about nine times more water than the U.S. cataract, is
about 640 m (about 2100 ft) long, and the fairly straight crest of the
American Falls measures 328 m (1075 ft). A small section of the American
Falls near Goat Island is also known as Bridal Veil Falls.Niagara Falls
was formed about 12,000 years ago, when glaciers retreated north,
allowing water from Lake Erie to flow over the Niagara
Escarpment, a ridge that extends in an arc across the northern Great
Lakes region, from Wisconsin to New York. Since that time, erosion has
slowly pushed the waterfall about 11 km (about 7 mi) upstream, forming
the Niagara Gorge. At present the Horseshoe Falls is receding at an
average yearly rate of about 1.5 m (about 5 ft), and the American Falls
is being cut away at an annual pace of about 15 cm (about 6 in). The
Horseshoe Falls erodes at a faster rate mainly because it carries more
water. In 1954 a considerable portion of the American Falls broke off,
creating a large talus, or rock slope, at the base of the cataract. In
order to study ways of preventing further rockfalls and to remove some
of the talus, the American Falls was successfully "shut off"
for several months in 1969 by a dam that was constructed between the
U.S. mainland and Goat Island.Niagara Falls is a great tourist
attraction, luring millions of visitors each year. The falls may be
viewed from parks located on either side of the river, from observation
towers, from boats, from Goat Island, and from the Rainbow Bridge,
located a short distance downstream. Visitors also may enter the Cave of
the Winds, situated behind a curtain of falling water near the base of
the American Falls.Samuel de Champlain,
a French explorer, probably visited Niagara Falls in 1613. Father Louis
Hennepin, a Flemish monk, is known to have visited the
waterfall in 1678; he later published an eyewitness description of it.The
Niagara's large volume of flow, averaging about 5520 cu m (about 194,940
cu ft) per second, plus its steep drop, give the river great power
potential. The waterpower probably was tapped first in 1757, when Daniel
Chabert Joncaire built a sawmill on the upper river. In 1853 work
started on a hydraulic canal to divert the waters of the upper river to
drive machinery in mills and factories situated below Niagara Falls. In
1875 the first flour mill powered by the canal water was opened, and in
1881 the first hydroelectric generator was installed along the waterway.
The first large-scale hydroelectric facility, the Edward Dean Adams
Power Plant, was opened on the U.S. side in 1896.In
1950 the United States and Canada signed a treaty fixing the amount of
water that could be diverted from the river for power generation, and
soon thereafter two major hydroelectric projects were constructed. The
Canadians built the twin Sir Adam Beck-Niagara generating stations (completed
1958; capacity, with associated pumped-storage facility, 1,815,000 kw)
at Queenston, Ontario. The Power Authority of the State of New York
constructed the Robert Moses-Niagara Power Plant (completed 1963;
capacity, with associated pumped-storage facility, 2,400,000 kw) near
Lewiston, New York. Both projects, each located about 6 km (about 4 mi)
below Niagara Falls, are driven by water diverted just above the falls
and conveyed by underground conduits and canals to turbines. Much of the
hydroelectricity is consumed by industries in the nearby cities of Niagara
Falls, New York, and Niagara Falls, Ontario.
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