Niagara Falls
Niagara Falls is a group of three waterfalls at the southern end of Niagara Gorge, spanning the border between the Canadian province of Ontario and the U.S. state of New York. The largest of the three is Horseshoe Falls, which straddles the international border of the two countries. It is also known as the Canadian Falls. The smaller American Falls and Bridal Veil Falls lie within the United States.
Formed by the Niagara River, which drains Lake Erie into Lake Ontario, the combined falls have the highest flow rate of any waterfall in North America that has a vertical drop of more than. During peak daytime tourist hours, more than of water goes over the crest of the falls every minute.
Bridal Veil Falls is separated from Horseshoe Falls by Goat Island and from American Falls by Luna Island, with both islands situated in New York. Horseshoe Falls is the most powerful waterfall in North America, as measured by flow rate. Niagara Falls is famed for its beauty and is a valuable source of hydroelectric power.
Balancing recreational, commercial, and industrial uses has been a challenge for the stewards of the falls since the 19th century. Niagara Falls is northwest of Buffalo, New York, and southeast of Toronto, between the twin cities of Niagara Falls, Ontario, and Niagara Falls, New York. Niagara Falls was formed when glaciers receded at the end of the Wisconsin glaciation, and water from the newly formed Great Lakes carved a path over and through the Niagara Escarpment en route to the Atlantic Ocean.
Etymology
states that the name of Niagara is abbreviated from Oniaagarah or Ochniagarah, called by the First Nations. It means "the thunder of waters".Philip D. Mason wrote this in his book Niagara: ''A Guide to the Niagara Frontier With Maps and Photographs'': "The word ‘Onguiaahra’ appears on maps as early as 1641. Both it and the later version, ‘Ongiara’ are Indian words generally interpreted as meaning ‘The Straight’, although the more romantic ‘Thunder of Waters’ is sometimes given. By the time the first white men arrived at the Falls, the name in general use was ‘Niagara’.... When the first white men settled here, Niagara was occupied by a tribe of Iroquois or Six Nations Indians, who had themselves driven out or annihilated the earliest recorded inhabitants, the Neutral Indians".
And Etymonline considers that it comes from Iroquoian and meaning "a neck".
Characteristics
The larger and taller Horseshoe Falls is about high, while the American Falls varies between in drop because of giant boulders at its base. Horseshoe Falls is about wide, while the American Falls is wide. The distance between the American extremity of Niagara Falls and the Canadian extremity is.The peak flow over Horseshoe Falls was recorded at. The average annual flow rate is. 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, at least of water traverse the falls, some 90% of which goes over Horseshoe Falls, while the balance is diverted to hydroelectric facilities and then on to American Falls and Bridal Veil Falls. This is accomplished by employing a weir – the International Control Dam – with movable gates upstream from Horseshoe Falls.
File:American Falls Niagara Falls USA from Skylon Tower on 2002-05-28.png|thumb|American Falls and Bridal Veil Falls
The water flow is halved at night and during the low tourist season in winter months, and only attains a minimum flow of. Water diversion is regulated by the 1950 Niagara Treaty and is administered by the International Niagara Board of Control. The verdant green color of the water flowing over Niagara Falls is a byproduct of the estimated 60 tonnes/minute of dissolved salts and rock flour generated by the erosive force of the Niagara River.
The Niagara River is an important bird area due to its impact on Bonaparte's gulls, ring-billed gulls, and herring gulls. Approximately 100,000 seagulls winter in the region, with it being common to spot 20,000 to 30,000 individuals daily between November and January. The river and waterfalls appeal to the birds due to their position on migratory routes, foraging potential, and unlikeliness to freeze over compared to other bodies of water.
Geology
The features that became the falls were created by the Wisconsin glaciation about 10,000 years ago. The retreat of the ice sheet left behind a large amount of meltwater that filled up the basins that the glaciers had carved, thus creating the Great Lakes as we know them today. Scientists posit there is an old valley, St David's Buried Gorge, buried by glacial drift, at the approximate location of the present Welland Canal.When the ice melted, the upper Great Lakes emptied into the Niagara River, which followed the rearranged topography across the Niagara Escarpment. In time, the river cut a gorge through the north-facing cliff, or cuesta. Because of the interactions of three major rock formations, the rocky bed did not erode evenly. The caprock formation is composed of hard, erosion-resistant limestone and dolomite of the Lockport Formation. That hard layer of stone eroded more slowly than the underlying materials. Immediately below the caprock lies the weaker, softer, sloping Rochester Formation. This formation is composed mainly of shale, though it has some thin limestone layers. It also contains ancient fossils. In time, the river eroded the soft layer that supported the hard layers, undercutting the hard caprock, which gave way in great chunks. This process was repeated countless times, eventually carving out the falls. Submerged in the river in the lower valley, hidden from view, is the Queenston Formation, which is composed of shales and fine sandstones. All three formations were laid down in an ancient sea, their differences of character deriving from changing conditions within that sea.
About 10,900 years ago, the Niagara Falls was between present-day Queenston, Ontario, and Lewiston, New York, but erosion of the crest caused the falls to retreat approximately southward. The shape of Horseshoe Falls has changed through the process of erosion, evolving from a small arch to a horseshoe bend to the present day V-shape. Just upstream from the falls' current location, Goat Island splits the course of the Niagara River, resulting in the separation of Horseshoe Falls to the west from the American and Bridal Veil Falls to the east. Engineering has slowed erosion and recession.
Future of the falls
The current rate of erosion is approximately per year, down from a historical average of per year. At this rate, in about 50,000 years Niagara Falls will have eroded the remaining to Lake Erie, and the falls will cease to exist.Preservation efforts
In the 1870s, sightseers had limited access to Niagara Falls and often had to pay for a glimpse, and industrialization threatened to carve up Goat Island to further expand commercial development. Other industrial encroachments and lack of public access led to a conservation movement in the U.S. known as Free Niagara, led by such notables as Hudson River School artist Frederic Edwin Church, landscape designer Frederick Law Olmsted, and architect Henry Hobson Richardson. Church approached Lord Dufferin, governor-general of Canada, with a proposal for international discussions on the establishment of a public park.Goat Island was one of the inspirations for the American side of the effort. William Dorsheimer, moved by the scene from the island, brought Olmsted to Buffalo in 1868 to design a city park system, which helped promote Olmsted's career. In 1879, the New York state legislature commissioned Olmsted and James T. Gardner to survey the falls and to create the single most important document in the Niagara preservation movement, a "Special Report on the preservation of Niagara Falls". The report advocated for state purchase, restoration and preservation through public ownership of the scenic lands surrounding Niagara Falls. Restoring the former beauty of the falls was described in the report as a "sacred obligation to mankind". In 1883, New York Governor Grover Cleveland drafted legislation authorizing acquisition of lands for a state reservation at Niagara, and the Niagara Falls Association, a private citizens group founded in 1882, mounted a great letter-writing campaign and petition drive in support of the park. Professor Charles Eliot Norton and Olmsted were among the leaders of the public campaign, while New York Governor Alonzo Cornell opposed.
Preservationists' efforts were rewarded on April 30, 1885, when Governor David B. Hill signed legislation creating the Niagara Reservation, New York's first state park. New York State began to purchase land from developers, under the charter of the Niagara Reservation State Park. In the same year, the province of Ontario established the Queen Victoria Niagara Falls Park for the same purpose. On the Canadian side, the Niagara Parks Commission governs land usage along the entire course of the Niagara River, from Lake Erie to Lake Ontario.
In 1887, Olmsted and Calvert Vaux issued a supplemental report detailing plans to restore the falls. Their intent was "to restore and conserve the natural surroundings of the Falls of Niagara, rather than to attempt to add anything thereto", and the report anticipated fundamental questions, such as how to provide access without destroying the beauty of the falls, and how to restore natural landscapes damaged by man. They planned a park with scenic roadways, paths and a few shelters designed to protect the landscape while allowing large numbers of visitors to enjoy the falls. Commemorative statues, shops, restaurants, and a 1959 glass and metal observation tower were added later. Preservationists continue to strive to strike a balance between Olmsted's idyllic vision and the realities of administering a popular scenic attraction.
Preservation efforts continued well into the 20th century. J. Horace McFarland, the Sierra Club, and the Appalachian Mountain Club persuaded the United States Congress in 1906 to enact legislation to preserve the falls by regulating the waters of the Niagara River. The act sought, in cooperation with the Canadian government, to restrict diversion of water, and a treaty resulted in 1909 that limited the total amount of water diverted from the falls by both nations to approximately. That limitation remained in effect until 1950.
Erosion control efforts have always been of importance. Underwater weirs redirect the most damaging currents, and the top of the falls has been strengthened. In June 1969, a temporary rock and earth dam was constructed, completely diverting the Niagara River from American Falls for several months. During this time, two bodies were removed from under the falls, including a man who had been seen jumping over the falls, and the body of a woman, which was discovered once the falls dried. While Horseshoe Falls absorbed the extra flow, the U.S. Army Corps of Engineers studied the riverbed and mechanically bolted and strengthened any faults they found; faults that would, if left untreated, have hastened the retreat of American Falls. A plan to remove the huge mound of talus deposited in 1954 was abandoned owing to cost, and in November 1969, the temporary dam was dynamited, restoring flow to American Falls. Even after these undertakings, Luna Island, the small piece of land between the American Falls and Bridal Veil Falls, remained off limits to the public for years owing to fears that it was unstable and could collapse into the gorge.
Commercial interests have continued to encroach on the land surrounding the state park, including the construction of several tall buildings on the Canadian side. The result is a significant alteration and urbanization of the landscape. One study found that the tall buildings changed the breeze patterns and increased the number of mist days from 29 per year to 68 per year, but another study disputed this idea.
In 2013, New York State began an effort to renovate Three Sisters Islands located south of Goat Island. Funds were used from the re-licensing of the New York Power Authority hydroelectric plant downriver in Lewiston, New York, to rebuild walking paths on the Three Sisters Islands and to plant native vegetation on the islands. The state also renovated the area around Prospect Point at the brink of American Falls in the state park.