Monday, October 19, 2009
The Niagara Falls are voluminous waterfalls on the Niagara River, straddling the international border between the Canadian province of Ontario and the U.S. state of New York. The falls are 17 miles (27 km) north-northwest of Buffalo, New York and 75 miles (120 km) south-southeast of Toronto, Ontario, between the twin cities of Niagara Falls, Ontario, and Niagara Falls, New York.
Niagara Falls is composed of two major sections separated by Goat Island: Horseshoe Falls, the majority of which lies on the Canadian side of the border, and 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.
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 six million cubic feet (168,000 m³) of water falls over the crest line every minute in high flow,[1] and almost 4 million cubic feet (110,000 m³) on average. It is the most powerful waterfall in North America.[2]
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 1800s.
Characteristics
Niagara Falls is divided into the Horseshoe Falls and the American Falls. The Horseshoe Falls drop about 173 feet (53 m), 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 volume of water approaching the falls during peak flow season may sometimes be as much as 202,000 cubic feet (5,700 m3) per second.[3] 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).[4] Viewpoints on the American shore generally are astride or behind the falls. The falls face directly toward the Canadian shore.
Geology
The features that became Niagara Falls were created by the Wisconsin glaciation, about 10,000 years ago. The same forces also created the North American Great Lakes and the Niagara River. All were dug by a continental ice sheet that drove through the area, deepening some river channels to form lakes, and damming others with debris.[5] Scientists believe that there is an old valley, 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 top rock formation was composed of erosion-resistant limestone and Lockport dolostone. That hard layer of stone eroded more slowly than the underlying materials. The aerial photo clearly shows the hard caprock, the Lockport Formation (Middle Silurian), which underlies the rapids above the Falls, and approximately the upper third of the high gorge wall.
Immediately below the hard-rock formation, comprising about two thirds of the cliff, lay the weaker, softer, sloping Rochester Formation (Lower Silurian). This formation was 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 repeated countless times, eventually carving out the Falls.
Submerged in the river in the lower valley, hidden from view, is the Queenston Formation (Upper Ordovician), 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.
The Niagara Falls at one time in history was located between present-day Queenston, Ontario, and Lewiston, New York, but erosion of their crest has caused the waterfalls to retreat approximately 6.8 miles or 11 kilometers southward. The Horseshoe Falls, which are approximately 2,600 feet (790 m) wide, have also changed their shape through the process of erosion; evolving from a small arch, to a horseshoe bend, to the present day gigantic inverted V.[6] Just upstream from the Falls' current location, Goat Island splits the course of the Niagara River, resulting in the separation of the Canadian Horseshoe Falls to the west from the American and Bridal Veil Falls to the east. Engineering has slowed erosion and recession.[7]
History
There are differing theories as to the origin of the name of the falls. According to Iroquoian scholar Bruce Trigger, "Niagara" is derived from the name given to a branch of the locally residing native Neutral Confederacy, who are described as being called the "Niagagarega" people on several late 17th century French maps of the area.[8]
A number of figures have been suggested as first circulating an eyewitness description of Niagara Falls. Frenchman Samuel de Champlain visited the area as early as 1604 during his exploration of Canada, and members of his party reported to him the spectacular waterfalls, which he described in his journals. Finnish-Swedish naturalist Pehr Kalm explored the area in the early 1700s and wrote of the experience. The consensus honoree is Belgian Father Louis Hennepin, who observed and described the Falls in 1677, earlier than Kalm, after traveling with explorer René Robert Cavelier, Sieur de la Salle, thus bringing the Falls to the attention of Europeans. Further complicating matters, there is credible evidence that French Jesuit Reverend Paul Ragueneau visited the Falls some 35 years before Hennepin's visit, while working among the Huron First Nation in Canada. Jean de Brébeuf also may have visited the Falls, while spending time with the Neutral Nation.[9]
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During the 18th century, tourism became popular, and by mid-century, it was the area's main industry. Napoleon Bonaparte's brother Jérôme visited with his bride in the early 19th century.[10] In 1837 during the Caroline affair a rebel supply ship, the Caroline, was burned and sent over the Falls. Demand for passage over the Niagara River led in 1848 to the building of a footbridge and then Charles Ellet's Niagara Suspension Bridge. This was supplanted by German-born John Augustus Roebling's Niagara Falls Suspension Bridge in 1855. After the American Civil War, the New York Central railroad publicized Niagara Falls as a focus of pleasure and honeymoon visits. With increased railroad traffic, in 1886, Leffert Buck replaced Roebling's wood and stone bridge with the predominantly steel bridge that still carries trains over the Niagara River today. The first steel archway bridge near the Falls was completed in 1897. Known today as the Whirlpool Rapids Bridge, it carries vehicles, trains, and pedestrians between Canada (through Canadian Customs Border Control) and the U.S.A. just below the Falls. In 1941 the Niagara Falls Bridge Commission completed the third current crossing in the immediate area of Niagara Falls with the Rainbow Bridge, carrying both pedestrian and vehicular traffic between the two countries and Canadian and U.S. customs for each country.
After the First World War, tourism boomed again as automobiles made getting to the Falls much easier. The story of Niagara Falls in the 20th century is largely that of efforts to harness the energy of the Falls for hydroelectric power, and to control the development on both sides that threaten the area's natural beauty.
Impact on industry and commerce
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Power
The enormous energy of Niagara Falls has long been recognized as a potential source of power. The first known effort to harness the waters was in 1759, when Daniel Joncaire built a small canal above the Falls to power his sawmill. Augustus and Peter Porter purchased this area and all of American Falls in 1805 from the New York state government, and enlarged the original canal to provide hydraulic power for their gristmill and tannery. In 1853, the Niagara Falls Hydraulic Power and Mining Company was chartered, which eventually constructed the canals which would be used to generate electricity. In 1881, under the leadership of Jacob Schoellkopf, Niagara River's first hydroelectric generating station was built. The water fell 86 feet (26 m) and generated direct current electricity, which ran the machinery of local mills and lit up some of the village streets.
When Nikola Tesla, for whom a memorial was later built at Niagara Falls, NY (USA), invented the three-phase system of alternating current power transmission, distant transfer of electricity became possible. In 1883, the Niagara Falls Power Company, a descendant of Schoellkopf's firm, hired George Westinghouse to design a system to generate alternating current. The world's first AC power generating and transmission plant was built at Ames, below Telluride, Colorado, by Westinghouse, Tesla and L.L. Nunn and proved effective by transmitting AC two miles at a loss of less than 5%. Four years later, by 1896, with financing from moguls like J.P. Morgan, John Jacob Astor IV, and the Vanderbilts, they had constructed giant underground conduits leading to turbines generating upwards of 100,000 horsepower (75 MW), and were sending power as far as Buffalo, 20 miles (32 km) away. The original designs for the power generating and transmission plants were created by the Swiss firm Faesch & Piccard. Private companies on the Canadian side also began to harness the energy of the Falls. The Government of the province of Ontario, Canada eventually brought power transmission operations under public control in 1906, distributing Niagara's energy to various parts of the Canadian province.
Other hydropower plants were also being built along the Niagara River. But in 1956, disaster struck when the region's largest hydropower station was partially destroyed in a landslide. The landslide drastically reduced power production and tens of thousands of manufacturing jobs were at stake. In 1957, Congress passed the Niagara Redevelopment Act, which granted the New York Power Authority the right to fully develop the United States' share of the Niagara River's hydroelectric potential.[11]
In 1961, when the Niagara Falls hydroelectric project first went on line, it was the largest hydropower facility in the Western world. Today, Niagara is still the largest electricity producer in New York State, with a generating capacity of 2.4 gigawatts (million kilowatts). Up to 375,000 US gallons (1,420 m3) of water a second is diverted from the Niagara River through conduits under the City of Niagara Falls to the Lewiston and Robert Moses power plants. Currently between 50% and 75% of the Niagara River's flow is diverted via four huge tunnels that arise far upstream from the waterfalls. The water then passes through hydroelectric turbines that supply power to nearby areas of the Canada and the USA before returning to the river well past the Falls.[12] This water spins turbines that power generators, converting mechanical energy into electrical energy. When electricity demand is low, the Lewiston units can operate as pumps, to transporting water from the lower bay back up to the plant's reservoir allowing this water to be used again during the daytime, when electricity use peaks. During peak electrical demand, the same Lewiston pumps are reversed and actually become generators, similar to those at the Moses plant.[11]
During tourist season, water usage by the power plant is limited by a treaty signed by the U.S. and Canada in 1950 in order to preserve this natural attraction. On average the Niagara river contains 1,500,000 US gallons (5,700 m3) of water per second, half of which half must flow over the falls during daylight hours from April through October. During other times the power plant may use up to three fourths of the total available water. During winter the Power Authority of New York works with Ontario Power Generation, to prevent ice on the Niagara River from interfering with power production and causing the flooding of shoreline property. One of their joint efforts is an 8,800-foot (2,700 m)–long ice boom, which prevents the buildup of ice, yet allows water to continue flowing downstream.[11]
The most powerful hydroelectric stations on the Niagara River are Sir Adam Beck 1 and 2 on the Canadian side, and the Robert Moses Niagara Power Plant and the Lewiston Pump Generating Plant on the American side. All together, Niagara's generating stations can produce about 4.4 GW of power. Edward Dean Adams[13] is the engineer credited with designing the system.
In August 2005 Ontario Power Generation, which is responsible for the Sir Adam Beck stations, announced plans to build a new 6.5 miles (10.5 km) tunnel to tap water from farther up the Niagara river than is possible with the existing arrangement. The project is expected to be completed in 2009, and will increase Sir Adam Beck's output by about 182 MW (4.2%).
Transport
Ships can bypass Niagara Falls by means of the Welland Canal, which was improved and incorporated into the Saint Lawrence Seaway in the middle 1950s. While the seaway diverted water traffic from nearby Buffalo and led to the demise of its steel and grain mills, other industries in the Niagara River valley flourished with the help of the electric power produced by the river. However, since the 1970s the region has declined economically.
The cities of Niagara Falls, Ontario, Canada and Niagara Falls, New York, USA are connected by three bridges: the Rainbow Bridge, just downriver from the Falls, which affords the closest view of the Falls and is open to non-commercial vehicle traffic and pedestrians; the Whirlpool Rapids Bridge, one mile (1.5 km) down from the Rainbow bridge and the oldest bridge over the Niagara river. The newest bridge, the Lewiston-Queenston Bridge, is located near the escarpment. Nearby Niagara Falls International Airport and Buffalo Niagara International Airport were named after the waterfall, as were Niagara University, countless local businesses, and even an asteroid.[14]
Preservation efforts
Niagara Falls has long been a source of inspiration for explorers, travelers, artists, authors, filmmakers, residents and visitors, few of whom realize that the falls were nearly to be solely devoted to industrial and commercial use. In the 1870s, sightseers had limited access to Niagara Falls and often had to pay merely for a glimpse, and industrialization threatened to carve up Goat Island in an effort 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. Mr 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 and helped promote Olmstead's career. Later, 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."[15] In 1883, 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. How would preservationists provide access without destroying the beauty of the falls? How would they 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.[16] 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.[17]
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 Niagara River.[18] 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 56,000 cubic feet (1,600 m³) per second. That limitation remained in effect until 1950.[19]
Erosion control efforts have always been of extreme importance. Underwater weirs redirect the most damaging currents, and the top of the falls have also been strengthened. In June 1969, the Niagara River was completely diverted away from the American Falls for several months through construction of a temporary rock and earth dam (clearly visible in the photo at left).[20] While the 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 which would, if left untreated, have hastened the retreat of the 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 the American Falls. Even after these undertakings, Luna Island, the small piece of land between the main waterfall and the Bridal Veil, remained off limits to the public for years owing to fears that it was unstable and could collapse into the gorge at any time.
Commercial interests have prevailed on the land surrounding the state park, however, with the recent construction of several tall buildings (most of them hotels) on the Canadian side. The result is a remarkable alteration and urbanisation of the landscape. It has also caused the airflow over the Falls to change direction.[21] The result is that the viewing areas on the Canadian side are now often obscured by a layer of mist.
Havasu Falls
The Havasu ’Baaja (meaning the-people-of-the-blue-green-waters), or more commonly the Havasupai, are a Native American tribe located in the northwestern part of the American state of Arizona. The tribe is well-known for being the only permanent inhabitants in the Grand Canyon, where they have lived for over 800 years. It also holds the distinction of being one of the only places left in America whose mail is still delivered by mule,[1] the other being Phantom Ranch.[2] But the main claim to fame for the Tribe is its richly colored waters and its awe-inspiring waterfalls, both of which have made this small community become a bustling tourist hub that attracts thousands of people every year.
Angel Falls (indigenous name: Parakupa-vena or Kerepakupai merú which means the fall from the highest point, in Pemon language; Spanish: Salto Ángel) is the world's highest waterfall, with a height of 979 m (3,212 ft) and a clear drop of 807 m (2,647 ft). It is located in the Canaima National Park (Spanish: Parque Nacional Canaima), a UNESCO World Heritage site, in the Gran Sabana region of Bolivar State, Venezuela.
The height of the falls is so great that before getting anywhere near the ground, the water is atomized by the strong winds and turned into mist. The mist can be felt a mile away. The base of the falls feeds into the Kerep River (alternatively known as the Rio Gauya), which flows into the Churun River, a tributary of the Carrao River.
In the indigenous Pemon language Angel Falls is called Kerepakupai merú meaning "waterfall of the deepest place". The falls are sometimes referred to as Churun-meru, an error, since that name corresponds to another waterfall in the Canaima National Park. Churun in the Pemon language means "thunder".
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Exploration
Sir Walter Raleigh described what was possibly a tepuy (table top mountain), and he is sometimes said to have discovered Angel Falls, but these claims are considered "far-fetched".[2] They were spotted in 1912 by the Venezuelan explorer Ernesto Sanchez La Cruz, but he did not publicize his discovery. They were not known to the outside world until American aviator Jimmie Angel[3] flew over them on 16 November 1933 on a flight while he was searching for a valuable ore bed.
Returning on October 9, 1937, Angel tried to land his Flamingo monoplane "El Rio Caroni" atop Auyan-tepui, but the plane was damaged when the wheels sunk into the marshy ground, and he and his three companions, including his wife Marie, were forced to descend the tepui on foot. It took them 11 days to make their way back to civilization, but news of their adventure spread, and the waterfall was named "Angel Falls" in his honor.
Angel's plane remained on top of the tepuy for 33 years before being lifted out by helicopter. It was restored at the Aviation Museum in Maracay and now sits outdoors on the front of the airport at Ciudad Bolívar.
The first recorded person to reach the river that feeds the falls was Latvian explorer Aleksandrs Laime, also known as Alejandro Laime to the native Pemon tribe. He made the ascent of Auyan-tepui in 1955. He also reached Angel's plane on the same trip, 18 years after the crash landing. He gave the river feeding the falls the name Gauja after a river in Latvia, but the Pemon-given name of the river, Kerep, is still widely used.
Laime also was the first to clear a trail that leads from the Churun river to the base of the falls. On the way, there is a viewpoint commonly used to capture the falls in photographs. It is named "Mirador Laime" ("Laime's Viewpoint" in Spanish) in his honor. This trail is used now mostly for tourists, to lead them from the Isla Raton camp to the small clearing.
The official height of the falls was determined by a National Geographic Society survey carried out by American journalist Ruth Robertson in 1949.[4]
A book by David Nott, Angels Four, chronicles the first successful climb up the face of Auyantepui to the top of the falls.
Tourism
Angel Falls is one of Venezuela's top tourist attractions, but even today a trip to the falls is not a simple affair. The falls are located in an isolated jungle region of Venezuela, and a flight from Caracas or Ciudad Bolívar is required to reach Canaima camp, the starting point for river trips to the base of the falls.
It is also possible to purchase a package that includes an aerial flyby of the falls. The falls cannot be seen on cloudy days, and there is no guarantee visitors will see them.
River trips generally take place from June to December, when the rivers are deep enough for the wooden curiaras used by the Pemon Indian guides. During the dry season (December to March) there is less water than is seen in some photos, but it is also more likely that the top will not be clouded.
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