By Ashley Karen
Tunnelling is officially underway on Toronto’s Scarborough 7.8-km Subway Extension.
Since late last year’s arrival from Germany, crews at the project’s launch shaft, located at Sheppard Avenue East and McCowan Road, have been actively preparing the excavation required to bring the tunnel boring machine (TBM) to life.
Teams have put multiple actions in place to safely and efficiently excavate the deep pit, such as building strong reinforced walls along the perimeter.
Over the next couple of years, Diggy Scardust, the Herrenknecht tunnel boring machine, will work 10 to 15 meters daily, driving its way south from the launch shaft site towards Eglinton Avenue East and Midland Avenue.
It will bore almost 6.9 kilometers of the 7.8-kilometre tunnel. In addition, the much-needed extension will carry subway service farther north into Scarborough and house approximately 105,000 daily boardings.
The contractor for the stations, rail and systems contract, Scarborough Transit Connect, a consortium of Aecon Infrastructure Management, FCC Canada and Mott MacDonald Canada, will construct the remaining part of the tunnel.
At 10.7 m wide, the three-station Scarborough extension is expected to be the first subway tunnel in Toronto to house two tracks working in both directions.
As tunnelling gets underway, teams have begun work at the project’s extraction shaft site at Midland Avenue and Eglinton Avenue East, where the tunnel boring machine is said to be removed from the ground after finishing its tunnelling journey.
In September 2021, Strabag received the award for the tunnel’s design, build and finance contract.
The Scarborough Subway Extension is one of four significant subway projects in the Greater Toronto area, illustrating the greatest subway expansion program in Canadian history.
The four projects comprise the Ontario Line, the Yonge North Subway Extension and the Eglinton Crosstown West Extension. They will add over 40km of new subway service to the rapid transit network.
For the latest information on the Scarborough Subway Extension, please visit the project website.
