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Ontario Line 3, targeted for completion in 2031, has notched a milestone with today’s announcement that construction is now underway along the entire length of the line. The final contract for the project includes the construction of the Don Valley Crossing Bridge and the West Don Crossing Bridge, which will carry subway trains across the meandering valleys between Don Mills and Downtown Toronto. The line is a significant piece of the multi-billion dollar expansion of rapid transit infrastructure now underway across the Greater Toronto and Hamilton area.
Travelling north from Cosburn station, the line will emerge from a tunnel at the north end of Minton Place, a short side street near the south end of the Leaside Bridge. From there, it will make its way over the Don Valley via the first bridge, continue via elevated guideway through Thorncliffe Park (where there is a station), then cross the West Don Valley before continuing as another elevated guideway to Flemingdon Park and Science Centre stations. At Science Centre station, Ontario Line 3 will interchange with Eglinton Line 5 (likely to open in 2025).
Looking west from the Leaside Bridge last month, preparatory work is underway for the installation of a crane at the construction site, just north of the Don Valley Parkway. The area has been cleared, with white tarp employed on the sloping earthworks to manage erosion and sediment control. The crane will hoist and place large structural components amid uneven terrain and over the busy expressway.
Another recent view from the Leaside Bridge highlights the preparatory groundwork underway on the north side of the valley, including excavators that are engaged in soil excavation and land-shaping in advance of constructing the piers for the bridge.
Looking south from the Leaside Bridge, this image depicts extensive tree removal and earthworks for the tunnel's emergence point from below Minton Place.
Phil Verster, President and CEO of Metrolinx, expressed enthusiasm about the project's progress, stating, "With partners selected to deliver on all the project’s contracts, and work underway across all parts of the Ontario Line, we are making significant progress in bringing more transit options to commuters. From end to end, the Ontario Line will cut transit journey times by more than half, going from 70 minutes to less than 30 minutes." In addition to reducing travel times, the Ontario Line will offer over 40 connections to subway, bus, streetcar, LRT, and GO train services.
Echoing the project's broader impacts, Nadia Todorova, Executive Director of the Residential and Civil Construction Alliance of Ontario (RCCAO), said of the investment, "After decades of underinvestment, RCCAO commends the Government of Ontario for investing in critical transportation infrastructure across the Greater Toronto Area to tackle congestion and boost economic growth."
Once completed, the Ontario Line will boast 15 stations stretching from Exhibition Place through Downtown Toronto to the Eglinton Line 5 Crosstown LRT at Don Mills Road. Excavation is underway for King-Bathurst, Moss Park, and Queen-Spadina stations, and will soon start for Corktown and Osgoode stations.
UrbanToronto will continue to follow progress on this development, but in the meantime, you can learn more about it from our Database file, linked below. If you'd like, you can join in on the conversation in the associated Project Forum thread or leave a comment in the space provided on this page.
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