World’s largest tunnel boring machine finishes drilling under Niagara Falls
From the Canadian Press: Amid much fanfare, rubble and dust, the world’s largest rock tunnel boring machine made a breakthrough deep below Niagara Falls, Ont., Friday and finally saw the light of day. The massive, 4,000-tonne machine, called Big Becky, had been boring a 10.2-kilometre long, 14.4-metre high tunnel under the city since 2006. Crowds…