Ontario subway line construction just took a big step closer to completion

Metrolinx shared on Monday, Oct. 26, that construction on the $5.6 billion Yonge North Subway Extension project just crossed yet another major milestone.

After announcing that the launch shaft for tunnel boring machines (TBMs) on the extension was ready to receive its mole-like machinery, Metrolinx has officially announced that the first of what will eventually be two TBMs working to carve out the line extension has arrived.

The machine isn't ready to start slinging massive amounts of soil quite yet, though: it's currently being assembled piece by piece at the York Region launch site.

Once assembly is complete, it and its soon-to-arrive sibling will bore twin tunnels northbound under Yonge Street, from Finch Station to the future High Tech Station.

The first of two TBMs arrives at the launch site.

The process is arduous, with crews assembling parts of the machine above ground and later lowering them directly down the shaft, but the machine's arrival does mark one major step closer to the project's completion.

The extension project will add five new stations north of Finch on the eastern arm of Line 1 and, Metrolinx estimates, will add over 90,000 additional trips on the route each day, reduce travel times by up to 22 minutes and cut greenhouse gas emissions by over 4,800 tonnes annually.

Though construction on the project is causing some major headaches for commuters in the short term, with a stretch of Yonge Street redirected until at least 2028, once construction is complete, it'll extend Line 1 by an impressive almost 8 kms.