
A Major OPG Clean-Energy Project
When someone says "Niagara Falls" what comes to mind? The spectacular Horseshoe Falls? The victory won at the Battle of Queenston Heights? How about the city's reputation as the Honeymoon Capital of the World? Now Canadians have another reason to be proud of Niagara Falls—the Niagara Tunnel, a major clean-energy project by Ontario Power Generation (OPG), Ontario's publicly owned power utility.
A Monster Tunnel
The largest hard rock Tunnel Boring Machine in the world has finished drilling a massive tunnel deep beneath the City of Niagara Falls. It is an incredible 14.4 metres (47.3 feet) wide and 10.2 kilometres (6.3 miles) long.
Olympic-Sized Volumes of Water
OPG planned this unheard-of feat of engineering to divert water from the Niagara River, and carry it downstream to the Sir Adam Beck Generating Stations. Gravity alone will propel the water at an incredible 500 cubic metres (17,660 cubic feet) per second. Think of it this way: that speed and volume of water would fill an Olympic-sized swimming pool in a matter of seconds.
Drilling for a Greener Future
OPG's Niagara Tunnel will be a source of pride not only as an engineering feat, but also as a practical solution for meeting Ontario's energy needs through clean sources. The Niagara Tunnel will allow OPG to provide enough clean water power to generate a further 1.6 billion kilowatt-hours of electricity annually–enough to meet the electricity needs of about 160,000 homes. Ontarians now and in the future will all benefit from the hard work taking place. With minimal maintenance costs, all this energy will be generated year-in, year-out for a hundred years or more.


How big is it? This Niagara Tunnel is 14.4 metres (47.3 feet) high—as high as a four-storey building. It's so big you could drive a double-stacked container freight train through it with plenty of room to spare.
Breakthrough Photos
Click on the thumbnails above for larger photos.
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Click here to download the Niagara Tunnel Project brochure (PDF). |
Click here to get some answers to some frequently asked questions about the new Niagara Tunnel.
Click here to watch a video clip on the project.
Tunnel Lining Video
Watch how the tunnel lining construction is progressing.







