Tunnel Boring Machine Completes Hole Under Niagara Falls 193
abhatt writes with news that "Big Becky," a 4,000-ton tunnel boring machine, has finished chewing through over 10 kilometers of rock underneath Niagara Falls, Ontario, a project that's been underway since 2006.
"The 10.2 kilometer tunnel is 14.4 meters in diameter. Big Becky ate through 1.6 million cubic meters of rock to reach her goal. That’s enough rock, officials said, to fill the Rogers Centre in Toronto. And the cement used to line the tunnel would build a sidewalk stretching from Windsor to Quebec City. ... The project took longer and cost more because Becky ran into unexpected conditions. She’s designed to go through solid rock, but encountered a stretch of loose, crumbling material that was unsuitable for tunneling. That forced a long and expensive detour."
Re:No, I'm not going to RTFA just to find out (Score:5, Interesting)
I thought they could already divert so much water through the hydropower tunnels that they have laws to mandate minimum flow rates at the falls to maintain the waterfall spectacle. Don't the new tunnels draw from the same water source?
http://www.niagarafallslocal.com/NiagaraFalls/showthread.php?t=60 [niagarafallslocal.com]
Feed for Sir Adam Beck power plant (Score:5, Interesting)
It's a feed tunnel for the Sir Adam Beck power plant [opg.com] below the falls. It's the third tunnel built for that purpose, and adds 194MW of generating capacity.
There's so much plumbing in place at Niagara Falls that the falls can almost be turned off. There's a minimum water flow over the falls established by international agreement, but that's for aesthetics. At night, and during the tourist off season, more water is run through the hydroelectric plants.
Back in the 1980s, some boater was upstream of the falls, closer than he should have been, and lost power. He managed to run aground upstream of the falls. This was noticed at the Niagara Mohawk power plant control room, where an operator opened all feed and diversion tunnels and closed gates at the upstream weir, shutting off most of the falls until a rescue crew could fetch the boater.