The Niagara Falls, located on
the Niagara River draining Lake Erie into Lake
Ontario, is the collective name for
the Horseshoe Falls and the adjacent American Falls along with the
comparatively small Bridal Veil Falls, which
combined form the highest flow rate of any waterfall in the world and has a
vertical drop of more than 165 feet (50 m). Horseshoe Falls is the most
powerful waterfall (vertical height along with flow rate) in North
America. Niagara Falls forms the international border between the
Canadian province of Ontario and the U.S. state of New York, also forming the
southern end of the Niagara Gorge. The falls are located 17 miles (27 km)
north-northwest of Buffalo, New
York and 75 miles (121 km) south-southeast of Toronto,
between the twin cities of Niagara Falls, Ontario, and Niagara
Falls, New York.
Niagara Falls are composed of
two major sections, separated by Goat Island: the Horseshoe Falls on the
Canadian side and the American Falls on the
American side. The smaller Bridal Veil Falls are also located on the American
side, separated from the main falls by Luna Island.
The international boundary line was originally drawn through Horseshoe
Falls in 1819, but the boundary has long been in dispute due to
natural erosion and construction.
Niagara Falls were formed when glaciers receded at the end
of the Wisconsin glaciation (the last ice age), and water from the newly formed
Great Lakes carved a path through the Niagara Escarpment en route to the
Atlantic Ocean. While not exceptionally high, the Niagara Falls are very wide. More than 6
million cubic feet (168,000 m3) of water falls over the crest line every minute
in high flow and almost 4 million cubic feet (110,000 m3) on average.
The Niagara
Falls are renowned both for their beauty and as a valuable
source of hydroelectric power. Managing the balance between recreational,
commercial, and industrial uses has been a challenge for the stewards of the
falls since the 19th century
The Horseshoe Falls drop about 173 feet (53 m), while the
height of the American Falls varies between
70–100 feet (21–30 m) because of the presence of giant boulders at its base.
The larger Horseshoe Falls are about 2,600 feet (790 m) wide, while the American Falls are 1,060 feet (320 m) wide. The distance
between the American extremity of the Niagara
Falls and the Canadian extremity is 3,409 feet (1,039
m).
The volume of water approaching the falls during peak flow
season may sometimes be as much as 202,000 cubic feet (5,700 m3, 5.7 million
liters) per second. Since the flow is a direct function of the Lake Erie water
elevation, it typically peaks in late spring or early summer. During the summer
months, 100,000 cubic feet (2,800 m3) per second of water actually traverses
the falls, some 90% of which goes over the Horseshoe Falls,
while the balance is diverted to hydroelectric facilities. This is accomplished
by employing a weir with movable gates upstream from the Horseshoe
Falls. The falls flow is further halved at night, and during the
low tourist season in the winter, remains a flat 50,000 cubic feet (1,400 m3)
per second. Water diversion is regulated by the 1950 Niagara Treaty and is
administered by the International Niagara Board of Control (IJC).
