Much of the downtown section of the subway was built directly underneath Yonge Street. Since the street could not possibly be closed during years of construction, the subway was built using the “cut and cover” method. First, vertical steel piles were driven into the ground every six feet on each side of the street to provide support for the sides of the tunnel excavation. Then, workers and machines began to dig downward from the street, making the “cut.” When the excavation was deep enough, horizontal steel beams were rested on the steel piles.

 

Planking on Yonge Street
Planking, Yonge Street looking south to Queen Street
October 18, 1949
Photographer: Canada Pictures Limited
City of Toronto Archives
Series 381, File 8, Item 6101-2

This image shows the one-foot-square timbers laid across steel horizontal support beams to provide a temporary surface for Yonge Street during construction.

Planking over excavation
Planking over excavation, looking south on Yonge Street to Queen Street
December 3, 1949
Photographer: Canada Pictures Limited
City of Toronto Archives
Series 381, File 20, Item 6288-3

Once the planking was in place, traffic, including streetcars, could continue as usual on Yonge Street.

 

Huge timbers one foot square were then set across the beams, forming a temporary street-level surface, the “cover”. This was for traffic to use while work continued below. In places where the subway ran beneath buildings, the foundations of those buildings were deepened and reinforced while workers tunnelled from one cut to another. Once the concrete walls, floor, and roof of the subway had been poured, the piles were cut off, the remaining space was filled with earth, and Yonge Street was repaved.

 

Excavation by hand, Yonge Street
Excavation by hand, Yonge Street north of Queen Street
September 28, 1949
Photographer: Canada Pictures Limited
City of Toronto Archives
Series 381, File 4, Item 5985-6

Excavation involved backhoes, dynamite charges to break up solid rock found south of Queen Street, and in some cases hand work with picks and shovels so that gas and electricity lines and water and sewage pipes were not damaged.

Exposed utility pipes and cables
Public utility wires and pipes, Yonge Street looking north from Queen Street
October 14, 1949
Photographer: Canada Pictures Limited
City of Toronto Archives
Series 381, File 6, Item 6045-3

Public utility conduits and pipes had to be located and then supported and protected during construction.

 

Exposed utility pipes and cables
Excavating by hand around public utility wires and pipes
October 14, 1949
Photographer: Canada Pictures Limited
City of Toronto Archives
Series 381, File 6, Item 6045-1
Exposed utility pipes and cables
Yonge Street looking south to Front Street from Melinda Street
March 16, 1950
Photographer: Canada Pictures Limited
City of Toronto Archives
Series 381, File 31, Item 6650-6

 

Excavation, Yonge and Front streets
Excavation, looking north on Yonge Street from just north of Front Street
September 28, 1949
Photographer: Canada Pictures Limited
City of Toronto Archives
Series 381, File 4, Item 5985-3

 

Rebuilding streetcar track
Rebuilding streetcar track on planking above subway excavation, Yonge Street looking north from near College Street
May 10, 1951
Photographer: Canada Pictures Limited
City of Toronto Archives
Series 381, File 124, Item 8234-5

 

Pile driver, Yonge and Front streets
Pile driver, Front Street west of Yonge, looking east
October 28, 1949
Photographer: Canada Pictures Limited
City of Toronto Archives
Series 381, File 11, Item 6147-4
Excavation for tunnel at Bloor Street
Looking south-west towards Yonge Street north of College
May 31, 1951
Photographer: Canada Pictures Limited
City of Toronto Archives
Series 381, File 130, Item 8307-14

North of College Street, the subway veered so that it was no longer directly underneath Yonge Street, but rather east of and parallel to it. Existing buildings were demolished to allow for cut and cover construction, and were later replaced with more modern ones. The tower visible is a former fire hall, converted into St. Charles Restaurant, at 484-88 Yonge Street.

 

Excavation for streetcar entrance, Bloor Street East
Excavation for entrance from streetcars to Bloor station, Bloor Street east of Yonge, looking east
June 25, 1951
Photographer: Canada Pictures Limited
City of Toronto Archives
Series 381, File 135, Item 8387-2

Two platforms, one for eastbound and one for westbound streetcars, were built in the centre of Bloor Street to allow passengers to walk from the streetcars directly down to the subway cars.

Tunnel excavation, Bloor and Yonge streets
Excavation for subway tunnel and Bloor station, Bloor Street east of Yonge Street, looking south-east
June 25, 1951
Photographer: Canada Pictures Limited
City of Toronto Archives
Series 381, File 135, Item 8387-1

This image shows another example of the cut and cover method in progress. The previously existing small buildings were replaced with a highrise office building at 33 Bloor Street East.

 

Excavation for streetcar tracks
Excavation for portal where surface tracks will enter underground station
June 26, 1951
Photographer: Canada Pictures Limited
City of Toronto Archives
Series 381, File 137, Item 8401-5
Excavation under Shuter Street March 17, 1950
Excavation under Shuter Street
March 17, 1950
Photographer: Canada Pictures Limited
City of Toronto Archives
Series 381, File 33, Item 6658-2

Backhoes used in the excavation were customized so they could be used in the restricted space. Dump trucks hauled out the soil and rock by way of several access ramps.

 

Building concrete form in tunnels
Building concrete forms north of Alexandra Street
January 1951
Photographer: Canada Pictures Limited
City of Toronto Archives
Series 381, File 96, Item 7823-7
Installing reinforcing rods for concrete
nstalling reinforcing rods for concrete
1950
Photographer: Canada Pictures Limited
City of Toronto Archives
Series 381, File 42, Item 6759-1

 

Steel forms (used as molds to contain the wet concrete in shape until it dried) were used in most areas, though plywood was used in control areas, passageways, and entrances. The steel forms were built in twenty-foot sections mounted on a frame that rested on rails on the floor. The forms could then be easily moved to the next area of the excavation.

 

Pouring concrete under ground
Pouring concrete at Yonge and Queen streets
March 23, 1950
Photographer: Canada Pictures Limited
City of Toronto Archives
Series 381, File 37, Item 6679-1
Queen subway station
Queen station
May 14, 1951
Photographer: Canada Pictures Limited
City of Toronto Archives
Series 381, File 125, Item 8251-4

 

The subway tunnels were entirely reinforced concrete, while the stations had, in addition, steel columns and structural beams. All concrete was mixed at a central plant offsite and pumped from trucks at street level using tubes that the TTC nicknamed “elephant trunks.”

 

Pouring concrete under ground
Preparing to pour concrete
February 2, 1951
Photographer: Canada Pictures Limited
City of Toronto Archives
Series 381, File 101, Item 7910-1
First section of platform, Queen Subway Station
First section of platform, Queen Station
February 15, 1951
Photographer: Canada Pictures Limited
City of Toronto Archives
Series 381, File 102, Item 7952-2

 

The arch of the roof in the stations conforms to structural design requirements, but was specially designed for visual effect as well. Original plans called for the centre supports (at the left of this image) to be concrete also, but they were instead made of steel columns to increase the feeling of spaciousness in the stations.

 

Excavation before pouring of concrete
Excavation as it appeared before pouring of concrete
December 11, 1950
Photographer: Canada Pictures Limited
City of Toronto Archives
Series 381, File 88, Item 7689-9
Reinforcing steel rods before concrete is poured
Excavation showing reinforcing steel rods before concrete is poured
June 26, 1951
Photographer: Canada Pictures Limited
City of Toronto Archives
Series 381, File 137, Item 8401-24

 

Excavation near Wellesley subway station
Excavation near Wellesley station
June 26, 1951
Photographer: Canada Pictures Limited
City of Toronto Archives
Series 381, File 137, Item 8401-18
Queen subway station, concrete complete
Queen station, concrete completed
October 25, 1951
Photographer: Canada Pictures Limited
City of Toronto Archives
Series 381, File 145, Item 8726-2

 

Looking north from Bloor subway station, under ground
Union station crossover
October 20, 1953?
Photographer: Canada Pictures Limited
City of Toronto Archives
Series 381, File 271, Item 11271-69

 

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