Tunnelling boring machine launched for Scarborough Subway Extension

Aug 12, 2023

TORONTO – Tunnelling officially got underway last week on the Scarborough Subway Extension project.

Tunnel boring machine (TBM) Diggy Scardust, which arrived from Germany late last year, started its journey on the 7.8-kilometre subway extension.

Crews at the project's launch shaft, located at Sheppard Avenue East and McCowan Road, have been preparing the excavation required to launch the TBM and put measures in place to safely and efficiently dig the deep pit, including building strong reinforced walls along the perimeter.

Over the next couple years, the TBM will travel 10 to 15 metres a day, making its way south from the launch shaft site towards Eglinton Avenue East and Midland Avenue, states the Metrolinx blog, adding it will dig about 6.9 kilometres of the 7.8-kilometre tunnel.

The remaining portion of the tunnel will be built by the contractor for the stations, rail and systems contract. This will be the first subway tunnel in the city to contain two subway tracks operating in both directions.

Crews have already started work at the project's extraction shaft site at Midland Avenue and Eglinton Avenue East where the TBM will be extracted from the ground after completing its tunnelling journey, adds the blog.