Line 1 Capacity Enhancement Program


The TTC’s Line 1, is the busiest rapid transit line in Canada, and plays a crucial role in moving people in Toronto and in the Greater Toronto region. Ridership on this portion of the line has grown consistently over the last 15 years and exceeds scheduled capacity south of Bloor-Yonge Station during the morning rush hour. This increased demand creates overcrowding conditions, which impact the passenger experience, system efficiency and reliability. Line 1 is closely integrated with the TTC network of surface routes, making more than 100 seamless connections with regional services at 13 stations. In 2031, ridership is forecasted to reach 36,000 passengers per hour southbound from Bloor-Yonge Station. This ridership increase is both from population and employment growth in the city of Toronto and the completion of the Line 1 Yonge subway extension to Richmond Hill. In 2007, a plan to increase capacity began with new higher capacity “walk-through trains” – the Toronto Rocket (TR) trains you see on Line 1 today. However, other system constraints continue to reduce, impede or limit the ability to achieve the required target capacities.

What we’re doing

The purpose of the Line 1 Capacity Enhancement Program, is first to identify all key system constraints that are hindering the TTC from increasing capacity on Line 1. The project will then look at specific target horizon years (2023, 2028, 2031 and 2037) and explore, assess and recommend improvements and solutions that address issues for the entire system and at individual stations where capacity constraints are identified.

Ridership has been increasing on Line 1 for more than a decade.

In April 2019, the Line 1 Capacity Requirements and Preliminary Implementation Strategy Report was issued. It outlines enhancement options and identifies where modifications, upgrades and new infrastructure is required to meet each of the milestone target capacities. The report also identified a high-level preliminary timeline and program cost, subject to further analysis and final approval.

Further work has begun to refine the enhancement options, and select what solutions are required with supporting studies, analysis and modelling. This work includes preliminary business case development. Specifically on Line 1, the TTC is considering the design and construction of a new maintenance and storage facility. We’re also working to upgrade fire ventilation, electrical traction power and substations, guideways and modifications at critical stations to increase capacity.

What are traction power substations?

  • Traction power substations provide electrical power to TTC subways and streetcars by transforming AC power from Toronto Hydro into DC power.
  • There are currently more than 50 TTC substations in the city, many in residential neighbourhoods.
  • Substations are quiet, very safe, and do not emit radiation, electricity or any harmful pollutants.
  • Substations need to be located about every two-and-a-half kilometres along the subway line.

Upgrading Fire Ventilation Systems on Line 1

  • To protect customers, a key component of the fire and life safety systems in the subway are fans and ventilation systems, which are installed in each station. Fire ventilation upgrades are required at key subway stations and emergeny services buildings.
  • High capacity ventilation fans vertically pull air into or push air out of the tunnels and stations, should fire or smoke enter the subway system.

Pilot Studies on Line 1

Our project team has also been analyzing the stations and train service on Line 1 looking at the real-world settings and considering innovative measures to improve service and customer experience. From this analysis, the TTC will be introducing pilot studies with unique tactics at some of our busiest stations. These tactics could be as simple as changing the direction of an escalator at different times of the day, adding new wayfinding decals and signs at a station or more innovative tactics that help shape travel preferences and patterns to reduce congestion. 

TTC and City staff have developed forecast demand projections for Line 1 that incorporate expected population and employment growth, along with future transit expansion projects and other initiatives.


  • Expanding capacity and improving circulation on Line 1
  • Less frequent overcrowding
  • Reduced travel times
  • More frequent trains on Line 1
  • Improved customer experience


Funding for the Line 1 Capacity Enhancements program, was listed in the January 2020 report, “TTC’s 2020-2029 Key Capital Investment Priorities: Subway Infrastructure and Accelerated Vehicle Procurement”.

The TTC Board approved key capital priorities for the application of $4.23 billion in net new funding made available through the dedicated City Building Fund and a one-time Federal Gas Tax amount. An estimated total of $1.50 billion was approved to begin the Line 1 Capacity Enhancement Program.

Next Steps

  • Finalize the Line 1 Capacity Enhancement Implementation Strategy Report and provide Stage Gate 1 deliverables, including preliminary business case, cost estimate and schedule.
  • Commence Stage Gate 2 – Feasibility and Conceptual Design for each selected enhancement option to establish a baseline definition for project scope, schedule and cost.


TTC Board Reports

TTC’s 2020-2029 Key Capital Investment Priorities (January 27, 2020)

Line 1 Capacity Requirements - Status Update and Preliminary Implementation Strategy (For Action) (April 11, 2019)


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