Imag shows a large portal being built.

The most common question from Leslieville and Riverside – Why can’t Metrolinx run the Ontario Line underground?

Metrolinx explains why running the Ontario Line in the existing rail corridor is not only the right approach for the community but also for an effective transit network.

Underground doesn’t mean less impact.

And it doesn’t mean being invisible.

Residents of Toronto’s Riverside and Leslieville communities have been asking Metrolinx if it’s possible to build a tunnel entrance east of the Don River, allowing Ontario Line trains to move under the GO train tracks, rather than building above ground in the existing rail corridor where GO and VIA trains run today.

But Metrolinx experts have found building an underground tunnel east of the Don River would be extremely disruptive to the communities and would erase many important customer benefits along the way.

Reducing construction disruptions

Before a subway line could be dug under the existing GO tracks, a portal would need to be built between Eastern Avenue and Queen Street. A portal is a large reinforced concrete structure that holds the earth in place to provide an opening for trains going in and out of the underground tunnel.

They’re big. Very big.

At the request of the community, Metrolinx experts have found that building a portal in this area would cause significant and lengthy community disruptions for Riverside and Leslieville, from soil excavation, utility relocation, concrete pouring, and many other construction activities. Traffic detours would be inevitable.

“Tunneling under a city isn’t an invisible solution to building needed transit,” said Phil Verster, Metrolinx President and CEO. “There’s a perception that digging below ground means less disruption but that is not necessarily the case. In fact, it’s not even feasible in certain locations.”

It would also require the acquisition of numerous homes along McGee and Saulter Streets and have significant impacts on the property currently home to Saulter Street Brewery, most of the parks in the area, and other small businesses and community organizations nearby.

Imag shows a large portal being built.
A portal is a reinforced concrete opening that creates a transition between above-ground tracks and underground tunnels. Burying the Ontario Line under the GO rail corridor would force Metrolinx to build a portal in the Riverside community, like this one on the Eglinton Crosstown, resulting in the permanent closure of either Eastern Avenue or Queen Street. Laying tracks in the existing GO rail corridor prevents this disruption. (Metrolinx image)

Steep concerns

Trains need to safely move from above ground to below. The maximum track grade, or steepness, of a track that is diving underground is 4.5 per cent. At this grade, a portal would need to be built in the area of Eastern Avenue and extend as far as Queen Street. Significant excavation to lower the levels of land would be needed to build a portal and retaining walls for the shallow tunnel structure. This would result in a permanent closure of Eastern Avenue or Queen Street, disrupting existing traffic and transit services. Worse, there would not be enough room for a station in Riverside.

To avoid that closure and still build a station, the streets and the existing bridges that run above them would need to be raised by at least two metres. Even then, there would not be sufficient space for a customer concourse in the station at Queen and De Grassi – only platforms.

Image shows a street shot.
To provide enough room for an underground station at Queen Street, the roadway and bridge would need to be raised at least two metres, resulting in major construction impacts for the community, especially the neighbouring Jimmie Simpson Recreation Centre and Park, and local street traffic. (Metrolinx image using Google Maps)

Eliminating the station would greatly reduce customer benefits – especially for people living in the immediate vicinity – and the much-needed relief for the 501 streetcar will be lost. The additional costs of this approach will exceed $800 million.

To avoid raising the road and the rail bridge would require a track incline steeper than what most subway vehicles in the world can manage.

Designing for the community

Metrolinx listened to concerns as part of its ongoing work to refine plans to better serve communities and protect public spaces. A key benefit of an above ground approach is the Ontario Line will fit almost entirely within the existing GO rail corridor that already runs through the community and bridges above Queen Street East and other nearby roads. Fitting work largely within that rail corridor will drastically reduce the community impacts of construction compared to tunneling underground.

Tracks will run beside the Jimmie Simpson Recreation Centre, which will stay open, and minimize disruption for businesses and homes during construction.

Metrolinx already had plans to upgrade and electrify the corridor under its GO Expansion program, so factoring the Ontario Line construction into that work also minimizes disruption. In particular, the above-ground alignment avoids at least five major excavations and dozens of utility disruptions that would have been needed in other areas of the local community, resulting in shorter construction times and far fewer impacts on homes and businesses. 

Electrified track also means quieter, cleaner train service.

A network approach to deliver faster transfer connections

In a growing, evolving and modern city such as Toronto, people want to travel for very different purposes, everything from daily commutes to leisure trips. To encourage them to leave their cars at home, public transit lines must be designed as part of a network that offers easy transfers to convenient connections.

For the Ontario Line, easy transfers will be especially important at East Harbour, the site of a new station just east of the Don River and north of Lake Shore Boulevard, in an area poised for growth. It will offer connections to and from TTC surface routes and GO trains (similar to connections at Exhibition station, but with even more passenger volume). Metrolinx expects 8,000 passengers will transfer between GO trains and the Ontario Line here each rush hour – with many more connecting from TTC routes through Riverside.

Quick and easy transfers will encourage people to use East Harbour to bypass Union Station. As more people use the Ontario Line, crowding at Union could go down by as much as 14 per cent – or 14,000 fewer people – during the busiest hour. This is a key benefit for the 200,000 passengers that pass through Canada’s busiest transit hub each day. And it’s a benefit that comes from designing the Ontario Line as a key connector – linking to the Eglinton Crosstown, TTC’s Line 1 and 2 subways, and GO’s Lakeshore East and West lines – within the broader transit network.

Some have suggested this station could be built underground with tracks going under the Don River. In addition to the serious environmental concerns around sensitive wetlands, tunnelling under the Don is not practical.

If the Ontario Line were tunneled through East Harbour, Riverside and Leslieville, all three stations south of the Danforth would need to be nearly 40 metres deep to go under the Don River and maintain a similar depth under Gerrard Street to avoid large sewer mains. That would be as deep as a nine-storey building is tall, requiring three separate escalators to get to the trains and adding four to five minutes to customers’ journeys – discouraging people from using the Ontario Line.

A station along the existing tracks above Queen Street East will make for faster commutes than one in such a deep tunnel and reduce transfer times for people connecting to and from streetcars on Queen.

This network approach and the environmental concerns are among the reasons why a subway in a deep tunnel under the Don River is not a good solution.

Delivering transit relief faster

Toronto residents have been demanding more transit choices for many years. Time is critical as a new line is needed to reduce crowding on the TTC’s Line 1 subway.

Using the existing corridor and putting the subway next to the GO tracks helps to deliver this new line on time. Tunneling through this area would delay completion between 15 and 24 months – also adding to the length of time the neighbourhood would be disrupted by construction.

The Ontario Line is more than twice as long as the old Relief Line South proposal and it is forecasted to be completed in a similar timeframe. While the latter had been discussed for years, it was still in the planning phase and the project budget and schedule had not been finalized, leaving it far from “shovel ready.”

A historic link

The rail line in this neighbourhood has a history that goes back to the 1850s and a Grand Trunk Railway station was built on the corner of Queen and De Grassi in 1896, with a heritage plaque now serving as a reminder.

The community has grown alongside an active rail line for more than a century-and-a-half. Now, it’s time to consider the future, and finally provide a public transit line for the neighbourhood.

What else is being done to support communities living alongside the Joint Rail Corridor?

Spaces where residents can relax and children can play are vital in communities. Homes, backyards and parks are important to our communities – now more than ever. As Metrolinx finalizes the design, the team is striving to minimize the impacts of construction and work with residents and community groups to keep them informed, engaged and involved as the plans evolve and work begins. If it becomes necessary to temporarily occupy some park spaces to support construction, and in so doing avoid impacts to nearby homes and businesses, Metrolinx will work with the city to ensure these are thoughtfully restored once the project is finished. Public consultation on the improvements planned for the rail corridor and any related mitigations will occur when the draft Early Works Report for the Lakeshore East Joint Rail Corridor is released later this year.

Providing ongoing access to parks will be a top priority for Metrolinx as the transit agency delivers this important subway project. Metrolinx will work with neighbours along the Ontario Line route to ensure access to park and playground spaces during construction.

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