This giant hole in the ground will eventually be one of the busiest TTC stations

A massive underground transformation is currently underway at the intersection of Queen Street West and Spadina Avenue, where excavation crews are carving out what will eventually become one of the busiest stations on the upcoming Ontario Line.  

In a recent construction committee presentation, Metrolinx provided an inside look at the cavern now taking shape beneath the intersection. Although it's difficult to picture it now, the enormous underground hole will one day house the Queen-Spadina station platform and connect the Ontario Line tunnel to the station's north and south entrances. 

Exacavation is ongoing, supported by round-the-clock work shifts 24 hours a day, seven days a week. The burdensome task includes not only rock removal but also the installation of shotcrete and rock bolts to provide structural support as the cavern is gradually widened and deepened. 

A look inside the cavern at the Queen-Spadina station site. Photo: Metrolinx.

The work is designed to accommodate tunnel boring machines as well as the full footprint of the future station platform and tracks. The current phase of rock breaking is expected to be completed by the end of August, with the cavern excavation targeted for completion by early 2026. 

In the coming weeks, construction crews will install a "pentabeam" structure to connect the station shaft with the cavern. The structure will eventually serve as a key passageway for riders accessing the Ontario Line platforms. Installation is expected to take approximately five to six weeks starting in early September. 

View from the entrance of the cavern at the Queen-Spadina north site. Photo: Metrolinx.

Construction also includes large-scale material removal using dump trucks and excavators, along with future phases of waterproofing and concrete lining for permanent structural support.

The forthcoming station's entrances will be placed directly next to TTC streetcar stops on the northeast and southwest corners, allowing riders to transfer between the Ontario Line and the 501 Queen or 510 Spadina routes without having to cross the busy intersection. 

By 2041, the station is expected to serve 7,200 customers during its busiest travel hour, and an estimated 3,800 transfers will take place at the station during peak periods. The surrounding area will include 22,800 residents and approximately 42,2000 jobs within walking distance. 

Future Ontario Line station building at the southwest corner of Queen Street West and Spadina Avenue. Photo: Metrolinx.

In addition to the massive station, the site is also being planned as a transit-oriented community (TOC), featuring two proposed 14 and 15-storey mixed-use residential towers. According to the provincial government, these buildings will deliver approximately 214 new housing units and 60 new jobs, with direct access to both the underground station and TTC streetcar service. 

Queen-Spadina is one of 12 TOC locations being proposed by the government along the Ontario Line, Yonge North Subway Extension, and Scarborough Subway Extension, which, collectively, aim to bring 56,000 new residential units and support roughly 75,000 jobs.