$5.6B subway extension project in Toronto just crossed a huge milestone

The Yonge North Subway Extension project crossed an important milestone on Thursday, with the official competition of excavation work for the launch shaft where tunnel boring machines will soon embark on an over six-kilometre voyage to extend the TTC's Line 1 - Yonge University subway.

The provincial government has announced that, after the removal of almost 70,000 cubic metres of soil to a depth of over ten metres, the launch shaft is ready to go ahead of the start of tunnelling for the extension's twin 6.3-kilometre tunnels

A pair of tunnel boring machines will eventually be lowered into the launch shaft, the construction of which requires a staggering 11,000 cubic metres of concrete and 860 tonnes of steel reinforcement, to carve away northbound on the extension.

The new extension will carry Line 1 approximately eight kilometres north from Finch Station to Vaughan, Markham and Richmond Hill, adding five new stations at Steeles, Clark, Royal Orchard, Bridge and High Tech.

Ontario Minister of Transportation, Prabmeet Sarkaria, hailed the milestone as evidence of "historic investments in public transit to protect Ontario's economy and keep people moving in the face of tariffs and economic uncertainty."

"The Yonge North Subway Extension will bring subway service to Markham and Richmond Hill for the first time ever, relieving gridlock and connecting thousands of people to housing and good-paying jobs," said Sarkaria.

Though the launch shaft is now excavated, don't expect tunnelling to begin overnight, as utility relocation work must precede future tunnelling and station construction.

The entire extension project was initially estimated to cost $5.6 billion, though a 2025 request for qualifications projected that the cost of stations, rails and systems alone would add up to $4 billion.

However, the suburban municipalities getting new subway service are excited regardless of the price tag.

Vaughan mayor  Steven Del Duca calls the construction milestone"an exciting step forward for the Yonge North Subway Extension." Del Duca notes that the extension will "bring a second subway line to Vaughan, further strengthening our links to Toronto and communities across the region."

Richmond Hill mayor David West says that the municipality has fought for a subway extension "for decades," adding, "today's tunnelling milestone demonstrates that this vision is becoming a reality."

"The completion of this phase of construction is an important step toward delivering faster, more reliable transit connections for residents and supporting the long-term economic vitality of our community."