As construction of the Scarborough subway extension gets underway, Metrolinx is sharing with the public how some of the methods being used are noteworthy ones for both Toronto and Canada.
“A special track has been built to run a line of construction trains into the tunnel as it is built to support the workers.”
The extension of the Bloor-Danforth Line 2 subway beyond Kennedy Station further into Scarborough began work in early 2023 as tunnelling commenced. The 7.8 km route with three new stations being built is scheduled to be completed in 2030.
One departure for the transportation agency is how the Scarborough extension will use only one tunnel.
“Unlike other Metrolinx subway projectslike the Eglinton Crosstown West Extension which will have two tunnels, one for each track, the Scarborough Subway Extension is being constructed as a single tunnel containing two subway tracks operating in opposite directions the first of its kind in Toronto,” Metrolinx told MPulse in a statement.
When passengers are travelling in currently operating TTC trains underground, they can only see the tunnel they are in. But once the extension opens, they will be able to see the train going the opposite direction, as they’re both within the same tunnel.
The other unique aspect of this project relates to the size of the tunnel being built. “At 10.7 metres in internal diameter, it will be the largest ever subway tunnel constructed in Canada, slightly larger than the Evergreen Line in Vancouver which is 8 metres in internal diameter,” Metrolinx told MPulse.
For now, a special track has been built to run a line of construction trains into the tunnel as it is built to support the workers. But eventually, that track will be replaced with larger one designed to accommodate the passenger subway trains.
“The construction trains operate on a narrow-gauge track used strictly during construction to bring tools and materials from the job site deeper inside the Scarborough Subway Extension tunnel as it is constructed,” Metrolinx explained.
“The future passenger rail will be built out as part of the Stations, Rails and Systems contract after the TBM has completed tunnelling. The excavated material is removed from the tunnel via a series of conveyor belts and deposited in dedicated chambers within the tunnel launch site muck pit, where awaiting trucks safely transport it to designated receiving sites.”
While the completion of the extension is a number of years away, Metrolinx projects than once complete the new stations will accommodate over 100,000 daily boardings.
