Excavation work has officially started on the launch shaft for the Ontario Line subway tunnels at Exhibition Station.

The Ontario government announced the news on November 22.

“It’s been more than 60 years since the first subway tunnels were built in downtown Toronto,” said Transportation Minister Prabmeet Sarkaria. “Under the leadership of Premier Ford, we’re getting the Ontario Line done to tackle gridlock and increase access to fast, reliable and affordable transit for millions of people across the GTA.”

The 16-metre-deep launch shaft will be the starting point for two tunnel boring machines that will dig six kilometres east, from Exhibition Station to the Don Yard, west of the Don River. Once tunnelling is complete, the launch shaft will be repurposed as a tunnel portal where Ontario Line trains will transition from above to below ground.

Exhibition Station will be a vital transit hub, serving both the future subway and existing GO rail customers. A trip across the city from Exhibition Place to the Eglinton Crosstown LRT at Don Mills Road will take 30 minutes or less compared to the hour and 10 minutes it takes today. The Ontario Line will offer more than 40 connections to other subway, bus, streetcar and regional train services, bringing hundreds of thousands more people within walking distance of transit.

"By preparing the launch shaft, we’ll soon be able to start tunnelling the Ontario Line. By building fast, underground transit, we’re providing people with more options and reducing gridlock,” said Infrastructure Minister Kinga Surma. “Our government is also seizing a unique opportunity to create transit-oriented communities that will bring more housing, jobs, retail and community amenities."

The 15.6-kilometre line will have 15 stations, running from Exhibition Place through the downtown core and connecting to the Eglinton Crosstown LRT at Don Mills Road.

During peak periods, the line is expected to reduce crowding by up to 15 percent on the busiest stretch, between Bloor-Yonge and Wellesley on the TTC's Line 1.

Meanwhile, work to build the line is expected to support 4,700 jobs construction annually over the next ten years.

The last time subway tunnelling was started through Toronto’s downtown core was in the late 1950s and early 1960s. In 1959, crews began construction on the segment of Line 1 that runs under University Avenue between Union and St. George stations. In 1962, work began on the first section of Line 2, which stretched between Keele and Woodbine stations.

As part of the Transportation Plan for the Greater Golden Horseshoe, the government is delivering Ontario’s priority transit projects, which include the largest subway expansion in Canadian history – the Ontario Line, the Scarborough Subway Extension, the Eglinton Crosstown West Extension and the Yonge North Subway Extension.