Niagara Falls

Niagara Falls is a set of massive waterfalls located on the Niagara River in eastern North America, on the border between the United States and Canada. Niagara Falls (French: les Chutes du Niagara) comprises three separate waterfalls: the Horseshoe Falls (sometimes called the Canadian Falls), the American Falls, and the smaller, adjacent Bridal Veil Falls. While not exceptionally high, Niagara Falls is very wide. With more than 6 million cubic feet (168,000 m³) of water falling over the crestline every minute in high flow, and almost 4 million cubic feet (110,000 m³) on average, it is the most powerful waterfall in North America

Geographically, Niagara Falls is located about Twenty (20) minutes away from the U.S. city of Buffalo and about an hour and a half (90 Minutes) away from the Canadian city of Toronto.

Some sources erroneously quote that the Niagara River has an average flow of about 12 million cubic feet per minute (200,000 cu ft/s) or even slightly more. This figure is derived from the average rate of flow (202,000 cu ft/s) of the Niagara River. This volume would pass over the falls if there were no hydroelectric water diversion upstream from the falls; however, water is diverted continuously from Niagara and this figure is approximately three times the actual average flow volume over the falls.

Niagara Falls is renowned for its beauty, and is both a valuable source of hydroelectric power and a challenging project for environmental preservation. A popular tourist site for over a century, the natural wonder is shared between the twin cities of Niagara Falls, Ontario and Niagara Falls, New York.

Formation

The historical roots of Niagara Falls lie in the Wisconsin glaciation, which ended some 10,000 years ago. The North American Great Lakes and the Niagara River are effects of this last continental ice sheet, an enormous glacier that crept across the area from eastern Canada. The glacier drove through the area like a giant bulldozer, grinding up rocks and soil, moving them around, and deepening some river channels to make lakes. It dammed others with debris, forcing these rivers to make new channels. It is thought that there is an old valley, buried by glacial drift, at the approximate location of the present Welland Canal.

After the ice melted back, drainage from the upper Great Lakes became the present-day Niagara River, which could not follow the old filled valley, so it found the lowest outlet on the rearranged topography. In time the river cut a gorge across the Niagara Escarpment, the north facing cliff or cuesta formed by erosion of the southwardly dipping (tilted) and resistant Lockport formation between Lake Erie and Lake Ontario. In doing so it exposed old marine rocks that are much older than the geologically recent glaciation. Three major formations are exposed in the gorge that was cut by the Niagara River.

When the newly established river encountered the erosion-resistant Lockport dolostone, the hard layer eroded much more slowly than the underlying softer rocks. 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 gorge wall. It is composed of very dense, hard and very strong limestone and dolostone.

Immediately below, comprising about two thirds of the cliff is the weaker, softer, and more crumbly and sloping Rochester Formation (Lower Silurian). It is mainly shale, though it has some thin limestone layers, and contains large quantities of fossils. Because it erodes more easily, the river has undercut the hard cap rock and created 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, and their differences of character derive from changing conditions within that sea.

The original Niagara Falls were near the sites of present-day Lewiston, New York, and Queenston, Ontario, but erosion of their crest has caused the waterfalls to retreat several miles southward. Just upstream from the Falls' current location, Goat Island splits the course of the Niagara River, resulting in the separation of the Horseshoe Falls to the west from the American and Bridal Veil Falls to the east. Although erosion and recession have been slowed in this century by engineering, the falls will eventually recede far enough to drain most of Lake Erie, the bottom of which is higher than the bottom of the falls. Engineers are working to reduce the rate of erosion to retard this event as long as possible.

The Falls drop about 170 feet (52 m), although the American Falls have a clear drop of only 70 feet (21 m) before reaching a jumble of fallen rocks which were deposited by a massive rock slide in 1954. The larger Canadian Falls are about 2,600 feet (792 m) wide, while the American Falls are 1,060 feet (323 m) wide. The volume of water approaching the Falls during peak flow season is 202,000 cubic feet per second (5,720 m³/s).[3][4] During the summer months, when maximum diversion of water for hydroelectric power occurs, 100,000 ft³/s (2,832 m³/s) of water actually traverses the Falls, some 90% of which goes over the Horseshoe Falls. This volume is further halved at night, when most of the diversion to hydroelectric facilities occurs.

Impact on industry and commerce

The enormous energy of the Falls was long recognized as a potential source of power. The first known effort to harness the waters was in 1759, when Daniel Joncairs 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, enough power was produced to send direct current to illuminate both the Falls themselves and nearby Niagara Falls village.

When Nikola Tesla, for whom a memorial was later built at Niagara Falls, 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. 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, twenty miles (32 km) away. Private companies on the Canadian side also began to harness the energy of the Falls, employing both domestic and American firms in their efforts. The Government of Ontario eventually brought power transmission operations under public control in 1906, distributing Niagara's energy to various parts of that province. 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 United States and Canada before returning to the river well past the Falls.

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.

In August 2005, Ontario Power Generation, which is now responsible for the Sir Adam Beck stations, announced plans to build a new 10.4 km (6½ mile) 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%).

Ships can bypass Niagara Falls by means of the Welland Canal, which in the 1960s was improved and incorporated into the Saint Lawrence Seaway. 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 until the 1970s with the help of the electric power produced by the river. Since then the region has declined economically.

The twin cities of Niagara Falls, Ontario and Niagara Falls, New York are connected by three bridges, including 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, 1.5 km (1 mi.) down from the Rainbow bridge and the oldest bridge over the Niagara river is open only to NEXUS Pass holders a limited amount of hours. 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.