Characteristics
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.[5] 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).[6]
The verdant green colour of the water flowing over the Niagara Falls is a byproduct of the estimated 60 tonnes/minute of dissolved salts and "rock flour" (very finely ground rock) generated by the erosive force of the Niagara River itself. The current rate of erosion is approximately 1 foot (0.30 m) per year down from a historical average of 3 feet (0.91 m) per year. However, it is estimated that 50,000 years from now, even at this reduced rate of erosion, the remaining 20 miles (32 km) to Lake Erie will have been undermined and the falls will cease to exist.[7]
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.[8] Scientists argue that there is an old valley, buried by glacial drift, at the approximate location of the present Welland Canal.
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.
About 10,900 years ago, the Niagara Falls 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 (10.9 km) southward.[9] 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.[10] 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.[11]
History
"Niagara Falls. This name is Mohawk. It means, according to Mrs. Kerr, the neck; the term being first applied to the portage or neck of land, between lakes Erie and Ontario. By referring to Mr. Elliott's vocabulary, (chapter xi) it will be seen that the human neck, that is, according to the concrete vocabulary, his neck, is onyara. Red Jacket pronounced the word Niagara to me, in the spring of 1820, as if written O-ne-au-ga-rah."[14]A number of figures have been suggested as first circulating an eyewitness description of Niagara Falls. The 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. The Finnish-Swedish naturalist Pehr Kalm explored the area in the early 18th century and is credited with the first scientific description of the falls. The consensus honoree for the first description is the Belgian missionary Louis Hennepin, who observed and described the falls in 1677, earlier than Kalm, after traveling with the 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 the 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.[15]
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.
A team from the U.S. Army Corps of Engineers dammed the falls in June 1969 in order to clear rock from the base of the falls. Rockslides had caused a significant buildup of rock at the bottom of the American side of the falls, and the engineers were to clean up the rock and repair some faults to prevent eventual erosion of the American side of the waterfall. A temporary dam was constructed to divert the flow of water to the Canadian side; the dam measured 600 feet (180 m) across and was made of nearly 30,000 tons of rock. The engineers cleared the rock debris and tested for safety, finishing the project in November of that year. Water flow was restored on November 25, 1969.[18]
Before the late 20th century the northeastern end of the Horseshoe Falls was in the United States, flowing around the Terrapin Rocks, which was once connected to Goat Island by a series of bridges. In 1955 the area between the rocks and Goat Island was filled in, creating Terrapin Point.[19] In the early 1980s the United States Army Corps of Engineers filled in more land and built diversion dams and retaining walls to force the water away from Terrapin Point. Altogether 400 feet (120 m) of the Horseshoe Falls was eliminated, including 100 feet (30 m) on the Canadian side. According to author Ginger Strand, the Horseshoe Falls is now entirely in Canada.[20] Other sources say "most of" Horseshoe Falls is in Canada.[21]
Impact on industry and commerce
Power
The Niagara Falls Power Company, a descendant of Schoellkopf's firm, formed the Cataract Company headed by Edward Dean Adams,[22] with the intent of expanding Niagara Falls power capacity. In 1890, a five-member International Niagara Commission headed by Sir William Thomson among other distinguished scientists deliberated on the expansion of Niagara hydroelectric capacity based on seventeen proposals, but could not select any as the best combined project for hydraulic development and distribution. In 1893, Westinghouse Electric (who had built the smaller scale Ames Hydroelectric Generating Plant near Ophir, Colorado two years earlier) was hired to design a system to generate alternating current on Niagara Falls, and three years after that this large scale AC power system was created (activated on August 26, 1895).[23] The Adams Power Plant Transformer House remains as a landmark of the original system.
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. Some of the original designs for the power transmission plants were created by the Swiss firm Faesch & Piccard, which also constructed the original 5,000 HP waterwheels.
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.[24]
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 U.S. 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 Canada and the United States before returning to the river well past the falls.[25] 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 transport 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.[24]
To preserve Niagara Falls' natural beauty, a 1950 treaty signed by the U.S. and Canada limited water usage by the power plants. The treaty allows higher summertime diversion at night when tourists are fewer and during the winter months when there are even fewer tourists.[26] This treaty, designed to ensure an "unbroken curtain of water" is flowing over the falls, states that during daylight time during the tourist season (April 1 to October 31) there must be 100,000 cubic feet per second (2,800 m3/s) of water flowing over the falls, and during the night and off-tourist season there must be 50,000 cubic feet per second (1,400 m3/s) of water flowing over the falls. This Treaty is monitored by the International Niagara Control Board. 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 or causing 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.[24]
The most powerful hydroelectric stations on the Niagara River are the 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. Together, Niagara's generating stations can produce about 4.4 gigawatts of power.
In August 2005 Ontario Power Generation, which is responsible for the Sir Adam Beck stations, started a major civil engineering project, called the Niagara Tunnel Project, to increase power production by building a new 12.7 metres (42 ft) diameter, 10.2 kilometres (6.3 mi) long water diversion tunnel. It was officially placed into service in March 2013, helping to increase the generating complex's nameplate capacity by 150 megawatts. It did so by tapping water from farther up the Niagara river than was possible with the preexisting arrangement. The tunnel provided new hydroelectricity for approximately 160,000 homes.[27][28]
Transport
The cities of Niagara Falls, Ontario, Canada and Niagara Falls, New York, U.S.A. are connected by two international bridges. The Rainbow Bridge, just downriver from the falls, affords the closest view of the falls and is open to non-commercial vehicle traffic and pedestrians. The Whirlpool Rapids Bridge lies one mile (1.6 km) north of the Rainbow Bridge and is the oldest bridge over the Niagara River. 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.[29]
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.
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.[31] 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.[32]
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.[33] 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.[34]
Commercial interests have continued to encroach on the land surrounding the state park, including the construction of several tall buildings (most of them hotels) on the Canadian side. The result is a significant alteration and urbanisation of the landscape. One study indicated it has caused the airflow near the falls to change direction. Students at the University of Guelph demonstrated, using scale models, that as air passes over the top of the new hotels it causes a breeze to roll down the south sides of the buildings and spill into the gorge below the falls, where it feeds into a whirlpool of moisture and air. The inference was that a documented rise in the number of "mist days" was a result of these breezes, where mist days refers to the mist plume of the falls reaching landside. In 1996 there were 29 mist days recorded, but by 2003 that number had risen to 68.[36] Another study has discounted this opinion and linked mist production primarily to the difference in air and water temperature at the falls. However, this study does not offer opinion as to why mist days have been increasing just that the hotel breezes are an unlikely cause.[37]
Over the falls
Jumps and plunges
On October 24, 1901, 63-year-old Michigan school teacher Annie Edson Taylor was the first person to go over the falls in a barrel as a publicity stunt; she survived, bleeding, but virtually unharmed. Soon after exiting the barrel, she said, "No one ought ever do that again."[38] Prior to Taylor's attempt, on October 19 a domestic cat named Iagara was sent over the Horseshoe Falls in her barrel to test its strength. Contrary to rumours at the time, the cat survived the plunge unharmed and later posed with Taylor in photographs.[39] Since Taylor's historic ride, 14 people have intentionally gone over the falls in or on a device, despite her advice. Some have survived unharmed, but others have drowned or been severely injured. Survivors of such stunts face charges and stiff fines, as it is illegal, on both sides of the border, to attempt to go over the falls.In 1918, there was a near disaster when a barge, known locally as the Niagara Scow, working upriver broke its tow, and almost plunged over the falls. Fortunately, the two workers on board saved themselves by grounding the vessel on rocks just short of the falls.[40]
Englishman Captain Matthew Webb, the first man to swim the English Channel, drowned in 1883 trying to swim the rapids down river from the falls.[41]
In the "Miracle at Niagara", Roger Woodward, a seven-year-old American boy, was swept over the Horseshoe Falls protected only by a life vest on July 9, 1960, as two tourists pulled his 17-year-old sister Deanne from the river only 20 feet (6 m) from the lip of the Horseshoe Falls at Goat Island.[42] Minutes later, Woodward was plucked from the roiling plunge pool beneath the Horseshoe Falls after grabbing a life ring thrown to him by the crew of the Maid of the Mist boat.[43][44]
On July 2, 1984, Canadian Karel Soucek from Hamilton, Ontario successfully plunged over the Horseshoe Falls in a barrel with only minor injuries. Soucek was fined $500 for performing the stunt without a license. In 1985, he was fatally injured while attempting to re-create the Niagara drop at the Houston Astrodome. His aim was to climb into a barrel hoisted to the rafters of the Astrodome and to drop 180 feet (55 m) into a water tank on the floor. After his barrel released prematurely, it hit the side of the tank and he died the next day from his injuries.[45]
In August 1985, Steve Trotter, an aspiring stunt man from Rhode Island, became the youngest person ever (age 22) and the first American in 25 years to go over the falls in a barrel. Ten years later, Trotter went over the falls again, becoming the second person to go over the falls twice and survive. It was also the second-ever "duo"; Lori Martin joined Trotter for the barrel ride over the falls. They survived the fall but their barrel became stuck at the bottom of the falls, requiring a rescue.[46]
On September 28, 1989, Niagara's own Peter DeBernardi (age 42) and Jeffery James Petkovich (age 25) became the first "team" to successfully make it over the falls in a two-person barrel. The stunt was conceived by Peter DeBenardi, who wanted to discourage youth from following in his path of addictive drug use. Peter was also trying to leave a legacy and discourage his son Kyle Lahey DeBernardi (age 2) from using addictive drugs. Peter DeBernardi had initially planned to have a different passenger. However, Peter's original partner backed out, and Peter was forced to look for an alternative. Jeffery Petkovich agreed to attempt the stunt with him. Peter claims he spent an estimated $30,000 making his barrel, made of steel and fiberglass, which had harnesses, reinforcing steel bands, and viewing ports. Peter's barrel also had a radio for music and news reports, rudders to help steer the barrel through the falls, oxygen, and a well-protected video camera to record the journey over the edge. They emerged shortly after going over with minor injuries and were charged with performing an illegal stunt under the Niagara Parks Act.[47]
On September 27, 1993 John "David" Munday, of Caistor Centre, Ontario, became the first known person to survive going over the falls twice.[48]
Kirk Jones of Canton, Michigan became the first known person to survive a plunge over the Horseshoe Falls without a flotation device on October 20, 2003. While it is still not known whether Jones was determined to commit suicide, he survived the 16-story fall with only battered ribs, scrapes, and bruises.[49][50]
A second person survived an unprotected trip over the Horseshoe Falls on March 11, 2009 and when rescued from the river, was reported to be suffering from severe hypothermia and a large wound to his head. His identity has not been released. Eyewitnesses reported seeing the man intentionally enter the water.[51][52]
On May 21, 2012, an unidentified man in his early 40s became the third person to survive an unprotected trip over the Horseshoe Falls. Eyewitness reports indicate that he "deliberately jumped" into the Niagara River after climbing over a railing.[53][54]
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