At dawn, Friday, December 7, the tunnel-boring machine (TBM) “Holey” broke through the “extraction shaft” headwall on the east side of William R. Allen Road, just north of Downsview Station.
In late July, Holey started its second tunnelling drive from a launch shaft at the site of the future Sheppard West Station and headed southbound toward the Downsview Subway Station. It tunneled 1.2 kilometers in its final drive and placed 793 tunnel liners as it proceeded. Holey has now finished its job for the TTC’s and City of Toronto’s project](http://www.ttc.ca/Spadina/index.jsp) to extend the 1 Yonge - University - Spadina subway line to York University and Vaughan.
You can watch how a TBM builds the tunnel and see the breakthrough near Downsvie on YouTube:
Crews started to remove Holey from the extraction shaft the week of December 10.
“Moley”, another tunnel-boring machine, has just achieved another milestone and by crossing under Kodiak Crescent. The TTC and its contractors expect Moley to arrive at Downsview soon.
You can view the progress of the four TBMs working the project — Holey and Moley and Yorkie and Torkie — here.