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, 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, 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, twenty miles (32 km) away. 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. 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.

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. The engineer credited with design of the system is Edward Dean Adams.[14]

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

Ships can bypass Niagara Falls by means of the Welland Canal, which was improved and incorporated into the Saint Lawrence Seaway in the 1960s. 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 until the 1970s. Since then 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.

From: en.wikipedia.org/wiki/Niagara_Falls