Niagara Tunnel Project

The Niagara Tunnel Project was part of a series of major additions to the Sir Adam Beck hydroelectric generation complex in Niagara Falls, Ontario, Canada.

Water delivered by the major new underground tunnel complements other upgrades to the Sir Adam Beck generating complex, resulting in a significant increase to the efficient use of the Niagara River's hydro power.

The project's new 12.7 metres (42 ft) diameter, 10.2 kilometres (6.3 mi) long tunnel was officially placed into service on 21 March 2013, helping to increase the generating complex's nameplate capacity by 150 megawatts, with the extra power produced enough for approximately 160,000 homes.

First constructed in 1922, the initial Sir Adam Beck power generating station, now abbreviated as SAB 1, derived its water supply from a hydro canal connected to the Welland River. However, due to increased power demand in later years, a second generating station, known as SAB 2, was constructed in 1954. It derives its water supply from two diversion tunnels, each about 9 kilometres (5.6 mi) in length. In 1958, a reservoir and the SAB Pump Station were constructed in order to make better use of available water by storing it during periods of low demand and using it in periods of greater demand in order to maximize the efficiency of the stations in regards to electricity supply and demand.

Between 1996 and 2005, Ontario Power Generation (OPG), which owns and operates the SAB complex, completed a series of major upgrades at the SAB 2 plant, increasing its potential generating nameplate capacity by 194 megawatts. Water delivered through the new Niagara Tunnel Project complements the SAB 2 upgrade, and results in an overall increase to the efficient use of the Niagara River's hydro power.

The new 10.2 kilometres (6.3 mi) long tunnel is 12.7 metres (42 ft) in diameter, or about four stories in height, and allows an additional diversion of a distant part of the Niagara River to reach the SAB plant complex at a rate of about 500 cubic meters (17,657 cubic feet) of water per second, a flow rate that can fill an Olympic-sized swimming pool in seconds. The Ontario Government considers the Niagara Tunnel Project and the Sir Adam Beck complex as integral to its efforts to close all of the province's coal-fired generating plants as part of its clean and green energy program.

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