Great Lakes Tunnel Boring Machine: How it works

Erika, a Tunnel advisor with Enbridge, gives a tour of the approximately 600-foot-long Tunnel Boring Machine to be used for the Great Lakes Tunnel Project, based on the working scale model now on display at our information center in St. Ignace, MI. While the cutterhead bores through rock under the Straits of Mackinac, other portions of the machine will build out and install a steel-reinforced concrete tunnel lining, house an operator cabin and move out excavated material through a slurry system.