Toronto: Excavation Starts for Ontario Line TBM Launch Site

In Toronto, excavation work has begun at Exhibition Station for the Ontario Line’s tunnel boring machine (TBM) launch site.

This marks the first subway tunnel construction project to take place in Toronto’s downtown core in more than six decades.

A 16-metre-deep launch shaft is being excavated to serve as the starting point for two TBMs. These TBMs will create twin tunnels spanning approximately six kilometres. The tunnels will extend from east of Exhibition Station to west of the Don River.

Upon completion of tunnelling, the launch shaft will be converted into a portal where Ontario Line trains will transition from elevated to underground tracks as they move eastward.

This announcement is the latest milestone in the construction of the Ontario Line, a planned 15.6-kilometre subway line designed to bring transit access within walking distance to an additional 227,500 Toronto residents.

In Spetember, work also began on building three of the new stations.