Scarborough Subway Extension hits 4km milestone
Canada's widest rapid transit tunnel is two-thirds complete, with the record-breaking dig on track to welcome first passengers by 2033.
The Scarborough Subway Extension has carved out more than four kilometres of tunnel — roughly 65 per cent of the 7.8-kilometre line that will stretch from Kennedy Station to Sheppard and McCowan.
Under construction since 2021, the $10-billion project is breaking records with its nearly 11-metre-diameter tunnel, the widest rapid transit void in Canada. Unlike typical twin-tunnel subway lines, this design carries both directions of track within a single massive chamber — wide enough to comfortably fit a three-storey building.
The tunnel-boring machine, dubbed Diggy Scardust in a nod to David Bowie and the machine's dig through Scarborough, has been making strong headway after earlier hiccups in the tunnelling phase. Metrolinx announced the four-kilometre milestone Monday morning.
The extension will replace the now-shuttered Scarborough RT with three new Line 2 stops. Current projections indicate the first passengers could board by 2033. For a city perpetually stuck in transit construction limbo, the visible progress feels like movement.