Toronto subway


The Toronto subway is a rapid transit system serving Toronto and the neighbouring city of Vaughan in Ontario, Canada, operated by the Toronto Transit Commission. It is a multimodal rail network consisting of three heavy-capacity rail lines operating predominantly underground, and one elevated medium-capacity rail line. Two light rail lines, which will operate both at-grade and underground, are under construction.
In 1954, the TTC opened Canada's first underground rail line, then known as the "Yonge subway", under Yonge Street between Union Station and Eglinton Avenue with 12 stations. As of 2018, the network encompasses 75 stations and of route. Over 216million unlinked rides were completed on the system that year, and with 1.58million riders every weekday, it is the busiest rapid transit system in Canada in terms of ridership.

Overview

There are four operating rapid transit lines in Toronto and two lines under construction:
Line 1 Yonge–University is the longest and busiest rapid transit line in the system. It opened as the Yonge subway in 1954 with a length of, and since then grew to a length of. Today, the line is U-shaped having two northern terminals looping on its southern end via Union station.
Line 2 Bloor–Danforth, opened in 1966, runs parallel to Bloor Street and Danforth Avenue between Kipling station in Etobicoke and Kennedy station in Scarborough. There is a plan to extend Line 2 three stops northeastward from Kennedy station to Sheppard Avenue and McCowan via Scarborough City Centre.
Line 3 Scarborough, originally known as the Scarborough RT, is an elevated medium-capacity rail line serving the city's eponymous suburban district. It opened in 1985 running from Kennedy station to McCowan station, passing. This is the only rapid transit line in Toronto to use Intermediate Capacity Transit System technology. There is a plan to close and dismantle Line 3 after Line 2 is extended to Scarborough Town Centre and Sheppard/McCowan.
Line 4 Sheppard opened in 2002 running under Sheppard Avenue East eastwards from Sheppard–Yonge station on Line 1 to Fairview Mall at Don Mills station; it is the shortest rapid transit line in Toronto.
Line 5 Eglinton is a light rail line under construction entirely along Eglinton Avenue, scheduled to open in 2022. The line will have 25 stations, of which 15 will be underground, while the remaining ten will be at-grade stops located in at the road's median.
Line 6 Finch West is an under-construction, 18-stop line travelling from Finch West station on Line 1 Yonge–University to the North Campus of Humber College, located mainly in the median of Finch Avenue. It is scheduled for completion in 2023, with an estimated cost of $1.2billion. Construction on Line 6 began in 2019.

History

Timeline of openings

Line 1 Yonge–University

Canada's first subway, the Yonge subway, opened in 1954 with a length of. The line ran under or parallel to Yonge Street between Eglinton Avenue and Union station. It replaced the Yonge streetcar line, Canada's first streetcar line. In 1963, the line was extended under University Avenue north to Bloor Street to connect with the Bloor–Danforth subway at the double-deck St. George station. In 1974, the line was extended from Eglinton station north to Finch station. The Spadina segment of the line was constructed north from St. George station initially to Wilson station in 1978, and in 1996 to Downsview station, renamed Sheppard West in 2017. Part of the Spadina segment runs in the median of Allen Road – an expressway formerly known as the Spadina Expressway – and crosses over Highway 401 on a bridge. Six decades of extensions gave the line a U-shaped route running from its two northern terminals and looping on its southern end at Union station. The latest extension from Sheppard West to opened on December 17, 2017, making the line long, over five times its original length.

Line 2 Bloor–Danforth

Opened in 1966, the Bloor–Danforth subway runs east–west under or near Bloor Street and Danforth Avenue. It replaced the Bloor streetcar line. Initially, the subway line ran between Keele station and Woodbine station. In 1968, the line was extended west to Islington station and east to Warden station, and in 1980, it was further extended west to Kipling station and east to Kennedy station.

Line 3 Scarborough

Opened in 1985, the Scarborough RT is a light metro line running from Kennedy station to McCowan station. The TTC started to construct the line to use Canadian Light Rail Vehicles. However, the provincial government forced the conversion to Intermediate Capacity Transit System technology because the province was funding the project and it owned a company that made the light metro vehicles. This line was never extended, and the current plan is to close and dismantle the line, replacing it with an extension of Line 2 to Scarborough Town Centre.

Line 4 Sheppard

Opened in 2002, the Sheppard subway runs under Sheppard Avenue from Sheppard–Yonge station to Don Mills station. The line was under construction when a change in provincial government threatened to terminate the project, but Mel Lastman, the last mayor of the former City of North York, used his influence to save the project. Despite the construction of many high-rise residential buildings along the line since its opening, ridership remains low resulting in a subsidy of $10 per ride. The line was intended to be extended to Scarborough Centre station, but because of the low ridership and the cost of tunnelling, there was a plan to extend rapid transit eastwards from Don Mills station via a surface light rail line, the Sheppard East LRT. However, in April 2019, Premier Doug Ford announced that the provincial government would extend Line 4 Sheppard to McCowan Road at some unspecified time in the future, thus replacing the proposed Sheppard East LRT.

Line 5 Eglinton

is funding the Line 5 Eglinton, a light rail line along Eglinton Avenue. From Mount Dennis in the west to Brentcliffe Road, the line will run almost entirely underground where Eglinton Avenue is generally 4–5 lanes wide. From east of Brentcliffe Road to Kennedy station, the line will operate on the surface in a reserved median in the middle of Eglinton Avenue, where the street is at least 6 lanes wide. Building on the surface instead of tunneling reduces the cost of construction on the eastern end of the line. The average speed of the line is expected to be ; as a comparison, the average speed of the heavy-rail Line 2 Bloor–Danforth is. The Eglinton line originated from Transit City, a plan sponsored by former Toronto mayor David Miller, to expedite transit improvement by building several light rail lines through the lower density parts of the city. Of the light rail lines proposed, only the Eglinton and Finch West line are under construction as of 2019. It is estimated to be completed in 2022.

Line 6 Finch West

, also known as the "Finch West LRT", is an under-construction line being built by Mosaic Transit Group along Finch Avenue. It is to be operated by the Toronto Transit Commission and was also part of the Transit City proposal announced on March 16, 2007. The, 18-stop line is to extend from Finch West station on Line 1 Yonge–University to the north campus of Humber College. The line is forecast to carry about 14.6million rides a year or 40,000 a day by 2031. It is scheduled for completion in 2023, with an estimated cost of $1.2billion. Construction on this line began in 2019.

Major incidents

On March 27, 1963, there was an electrical short in a subway car's motor. The driver decided to continue operating the train, despite visible smoke in the affected car, until the train reached Union station. This decision resulted in the destruction of six subway cars and extensive damage to the tunnel and signal lines west of Union station. Following this incident, safety procedures involving electrical malfunctions and/or fire in subway trains, were revised to improve safety and reduce the likelihood of a similar incident occurring.
On October 15, 1976, arson caused the destruction of four subway cars and damage to Christie station, resulting in the closure of part of the Bloor–Danforth line for three days, and the bypassing of Christie station for some time afterwards for repairs.
On August 11, 1995, the TTC suffered the deadliest subway accident in Canadian history, known as the Russell Hill accident, on the Yonge–University line south of St. Clair West station. Halfway between St. Clair West and Dupont stations, a southbound Line 1 subway train hit the rear of a stationary train ahead of it. Three people died and 100 other people were injured, some of them seriously. This led to a major reorganization at the TTC, with more focus on maintaining a "state of good repair" and less on expansion.

Operations and procedures

Terminal station reversals and short turns

The heavy-rail subway lines were built in multiple segments with multiple crossovers. These are typically used for reversals at terminal stations, and allow arriving and departing trains to cross to and from the station's farside platform. They are also used for short turning trains at some through stations in order to accommodate emergency and planned service suspensions. Planned service suspensions generally occur on weekends for planned maintenance activities that are impractical to perform overnight. There is only one regular short turn service that occurs during the morning rush hour on Line 1 Yonge–University when some northbound trains short turn at .
On Line 3 Scarborough, light metro trains cannot switch directions except at the ends of the line as there are no intermediate crossovers between the two termini. Thus, there can be no short turns on Line 3.

Door operation

The heavy-rail subway Lines 1 and 2 use a two-person crew, one to operate the train and another at the rear of the train to operate the doors. On October 9, 2016, Line 4 Sheppard was converted so that one person both drives the train and operates the doors.
With a two-person crew, an on-board train guard is responsible for opening and closing the subway car doors, and making sure no one is trapped in a door as the train leaves a station. From the subway's inception in 1954 to 1991, the train guard notified patrons that the subway car doors were closing with two short blasts from a whistle.
In a 2016 presentation, a timeline indicated Line 1 would be converted to one-person operation by 2019, and Line 2 would follow in 2021.
In 1991, as a result of lawsuits, electronic chimes, in the form of a descending major triad and a flashing pair of orange lights above the doorway, added for the hearing impaired, were tested and gradually introduced system-wide during the 1990s. The Toronto Rocket trains use the same door chimes and flashing orange lights as the older trains do, and also plays the additional voice announcement, "Please stand clear of the doors". Those chimes have become synonymous with the TTC and Toronto to the point that the CBC Radio One local afternoon show, Here and Now, includes them in its theme music.

Entering a station

There are several basic procedures that need to be completed once a train has entered a station. On TTC's Lines 1 and 2, several symbols of different colours are installed on the station wall for the crew to use as a reference in positioning the train in the platform. A red circle, located at the train exit end of the platform, should be directly in front of the train operator's cab window when the train is aligned properly. A green triangle, located at the opposite end of the platform, is provided as a reference to the train guard that shows that the train is correctly aligned. Before opening the train doors, the guard lowers the cab window and points their finger out the window toward the green triangle when the cab is lined up with the triangle. If the train is not lined up properly, the guard is not permitted to open the doors.
To operate the doors, the guard is first required to insert and turn a key. This action provides system control to the door control panel. The doors are then opened by pushing buttons. After the doors are opened, the guard is required to stick their head out the cab window to observe passengers boarding and exiting. The train doors remain open for at least 15 seconds.
When the guard determines that boarding is complete, the doors are closed. Electronic chimes and flashing lights are turned on, then the automated announcement "please stand clear of the doors" is played over the train's public address system, and finally the doors are closed. The chimes provide a clear notification and warning to passengers that the doors are closing and are played before the automated announcement is played, because such announcements may not be heard when the station is crowded.
After the doors are closed, the guard provides a signal to the train operator that the train can proceed. The signal is in the form of a green light that turns on inside the operating cab. When the doors are closed, a light turns on in the operating cab. The guard is instructed to visually observe the platform while the train departs the station. The distance for this visual inspection is typically three car lengths. An orange triangle installed on the station wall indicates the location where the guard may stop observing the platform and pull their head back into the cab. This is done to ensure that no passengers are being dragged along by the train.

Platform markers

All staffed subway operations must verify that the train is properly berthed before the doors are opened. At each subway platform, a set of three six-inch wide platform markers are affixed onto the platform wall. The train operator and guard use them to position the train.
The current platform markers used for Lines 1, 2, and 4 are as follows:
Prior to 2017, when subway guards operated the doors from the fifth car instead of the trailing car in the T1 trains on Line 2, different platform markers were used. The following markers have now fallen into disuse as a result of a March 2017 policy change that required all guards to work from the trailing car on Line 2:The platform markers previously used for Line 2 are as follows:
During rush hour, up to 65 trains are on Line 1 simultaneously, 45 trains on Line 2, 5 trains on Line 3, and 4 trains on Line 4. During non-rush hour periods, there are 30–46 trains on Line 1 at any one time.
On weekdays and Saturday, subway service runs from approximately 6:00am to 1:30am; Sunday service begins at 8:00am. Start times on holidays may vary.

Station announcements

On January 8, 1995, train operators began to announce each stop over the train's speaker system as a result of pressure from advocacy groups for the visually impaired, but announcements were sporadic until the TTC began to enforce the policy circa 2005. Later, automated announcements were implemented under further pressure from the advocacy groups. All Toronto subway trains use an automated system to announce each station which is played twice over the speaker system: when the train departs a station and when it arrives at the following station. In addition, the TTC's new Toronto Rocket subway trains provide visible and audible automatic stop announcements. Unlike the other trains, the Rockets also announce interchange stations, such as "Change for Line 2", and terminus stations, "This is a terminal station" where applicable., they also announce, except at terminus stations, which side the train doors will open on at each stop based on direction of train travel.

Winter operations

Switches and power rails are vulnerable to malfunction under extreme winter conditions such as heavy snow or freezing rain. During such events, the TTC runs "storm trains" overnight to keep power rails clear of ice. The TTC also has trains to apply an anti-freeze to the power rail once freezing rain starts. These precautions are also used on Line 3 Scarborough, which uses two power rails.
To keep switches in the yards from freezing, crews use switch heaters and manually monitor them to ensure they stay in working order during the winter storm. Workcars are run as storm trains to prevent ice from building up on the power rails within the yards.

Stations

The Toronto subway has 75 stations divided into four lines. Most stations are named for the nearest major arterial road crossed by the line in question. A few are named for major landmarks, such as shopping centres or transportation hubs, served by the station. The stations along the University Avenue section of the Yonge–University line, in particular, are named entirely for landmarks and public institutions and major churches.
feature a terminal that connects riders to other TTC services.
All trains, except for short turns, stop at every station along their route and run the entire length of their line from terminus to terminus. Nearly all stations outside the central business district have terminals for local TTC bus routes and streetcar routes situated within their fare-paid areas.
By December 23, 2016, Presto card readers had been installed in at least one priority subway station entrance across the TTC network. Throughout 2017 and into mid-2018, the remaining subway station entrances that still use legacy turnstiles and the "floor-to-ceiling" revolving turnstiles were replaced by the new Presto-equipped "glass-paddle" fare gates.

Accessibility

A growing number of Toronto's subway stations are accessible to wheelchair users in general and riders with accessibility issues. Upgrade plans to stations call for all stations to be barrier-free and have elevator access by 2025.

Cleanliness

The May 2010 TTC cleanliness audit of subway stations found that none of them meet the transit agency's highest standard for cleanliness and general state of repair. Only 21 stations scored in the 70–80% range in the TTC's cleanliness scale, a range described as "Ordinary Tidiness", while 45 fell in the 60–70% range achieving what the commission describes as "Casual Inattentiveness". The May audit was the third in a series of comprehensive assessments that began in 2009. The commission announced a "Cleaning Blitz" that would add 30 new temporary cleaners for the latter part of 2010 to address major issues and has other action plans that include more full-time cleaners, and new and more effective ways at addressing station cleanliness.

Public art

According to a 1991 CBC report, "aesthetics weren't really a priority" on Toronto's subway system describing stations as "a series of bathrooms without plumbing." Since that time, Toronto's subway system has had over 30 pieces installed in various subway stations. More art appears as new stations are built and older ones are renovated. The main article has a list of artwork by line and station.
For example, USA Today said of the Sheppard subway line: "Despite the remarkable engineering feats of this metro, known as Sheppard Subway, the art covering walls, ceilings, and platforms of all five stations that stands out. Each station is 'a total art experience where artists have created imaginative environments, uniquely expressing themes of community, location, and heritage' through panoramic landscapes and ceramic wall murals."

Internet and mobile phone access

On December 13, 2013, Wi-Fi Internet access was launched at and St. George stations. The ad-supported service is provided by BAI Canada, who have agreed to pay $25million to the TTC over a 20-year period for the exclusive rights to provide the service. TTC/BAI Canada plan to offer TConnect at all underground stations. Commuters have to view a video advertisement to gain access to the Internet. It is expected that all of the 69 subway stations will have service by 2017, as well as the six stations along the Line 1 extension to Vaughan. From early December 2015 to late January 2016, users of TConnect were required to authenticate themselves using a Twitter account, whose Canadian operations sponsored the TConnect Wi-Fi network. Users of the network can sign in to enable an automatic Wi-Fi connection for 30 days. This arrangement was resumed on an optional basis from July 2016 to late November/early December 2016.
, the Wi-Fi network is available at all existing stations, including the stations, and will be available in all future stations.
On June 17, 2015, the TTC announced that Wind Mobile customers could access cellular connectivity at some TTC subway stations. BAI Canada has built a shared Wi-Fi and cellular infrastructure for the TTC that allows any wireless carrier to sign on and provide underground cellular service to their customers. Wind, as the launch carrier, had a one-year period of exclusivity, which expired in June 2016. Since July 1, 2016, the shared cellular DAS had been open for other carriers to join. Cellular services are available at 28 stations with service at additional stations having been added in December 2016, including the stations in the extension to Vaughan Metropolitan Centre station. The tunnels from St. Patrick station to Bloor–Yonge station also have cellular service.

Naming

The TTC considers multiple different factors when they name stations and stops for subway and LRT stations. They consider local landmarks, the cross streets of the station, distinct communities of the past and present in the vicinity of the station, names of other stations in the system, and the grade of the station.
Metrolinx uses five criteria for naming stations and stops. These are:
  1. Simplicity
  2. Names must be logical and relevant to the area the station is built in
  3. Names should be relevant for the life of the station
  4. Names should help passengers locate themselves within the region
  5. Uniqueness
Metrolinx also uses the word "stop" in place of "station" at 10 of the 25 stations along Line 5, particularly those that are not grade-separated.

Rolling stock

The following table shows the vehicle type by line:

Heavy rail stock

Lines 1, 2 and 4 use two types of vehicles: the new Toronto Rocket trains on Line 1 Yonge–University and Line 4 Sheppard, and the older T1 trains on Line 2 Bloor–Danforth. Because of shorter station platforms, Line 4 uses four-car TR trains.
The TTC's original G-series cars were manufactured by the Gloucester Railway Carriage and Wagon Company. All subsequent heavy-rail subway cars were manufactured by Bombardier Transportation or one of its predecessors. All cars starting with the Hawker Siddeley H series in 1965 have been built in Bombardier's Thunder Bay, Ontario plant. The final H4 subway cars were retired on January 27, 2012. This was followed by the retirement of the H5 subway cars, which had their final in-service trip on June 14, 2013, and the H6 retirement, which followed one year later with a final run on June 20, 2014.
Following the introduction of the Toronto Rockets on Lines 1 and 4, all the T1 trains have been moved to Line 2. The T1s are expected to last until up to 2026.

Light metro stock

uses 28 S-series trains built by the Urban Transportation Development Corporation in Millhaven, Ontario. These Intermediate Capacity Transit System trains are Mark I models, similar in design to the original trains found on the Vancouver SkyTrain. These are the original vehicles of the Scarborough RT and have been in service since the line's opening in 1985. Because of the trains' age, they have been refurbished for operation until the extension of Line 2 Bloor–Danforth is built.

Light rail stock

Metrolinx plans to use 76 Bombardier Flexity Freedom low-floor, light-rail vehicles for Line 5 Eglinton; however, 44 Alstom Citadis Spirit vehicles may be used if Bombardier is unable to deliver the Flexity Freedom on time. Such a substitution would require modifications to Line 5, especially the maintenance facility, as the Citadis Spirit is longer than the Flexity Freedom. Metrolinx intends to use 17 Citadis Spirit vehicles on the planned Line 6 Finch West instead of the Flexity Freedom.
VehicleAlstom Citadis SpiritBombardier Flexity Freedom
Length
Maximum capacity292164
Maximum speed

Technology

The heavy rail and light metro lines have some characteristics in common: Such lines are fully isolated from road traffic and pedestrians; the station platforms are covered, and the trains are boarded through many doors from high platforms within a fare-paid zone separated by faregates.
In contrast, the surface portions of the light rail lines will fit into the street environment. Light-rail tracks will be laid on the surface within reserved lanes in the middle of the street, and cross street intersections at grade. Surface stations will have simple, low-level platforms. However, like heavy rail and light metro, passengers will be able to board and alight the light rail trains by multiple doors.
The light metro on Line 3 uses a more complex technology than heavy rail, which a TTC document describes as follows:

Signals

Heavy rail

signalling has been used throughout the subway system since the opening of Toronto's first subway in 1954., fixed block signalling is used on most of Line 1 and on the full length of lines 2 and 4. Along with automatic signalling, used to prevent rear-end train collisions, interlocking signals are used to prevent collisions from conflicting movements on track crossovers.
In 2009, the TTC awarded a contract to Alstom to upgrade the signalling system of the existing section of Line 1, as well as equip its extension into Vaughan, with moving block-based communications-based train control by 2012. This automatic train control project will cost $562million, $424million of which is funded by Metrolinx. With ATC, the TTC will be able to reduce the headway between trains from 2.5 minutes to 2 minutes during rush hours, and allow a 25 percent increase in the number of trains operating on Line 1.
Deadlines for the complete conversion of Line 1 were pushed back to 2016 and again to 2018. The first section of the "Urbalis 400" ATC system on Line 1 entered revenue service on December 17, 2017, between Sheppard West to Vaughan Stations in conjunction with the opening of the TYSSE project. In December 2018, ATC operation was extended south from Sheppard West to Dupont, and was planned to be cover the whole line by 2019. By December, it was revealed that ATC conversion will not be complete by 2019. ATC is now scheduled to be fully deployed in phases on the remainder of Line 1 by 2022. The TTC then plans to convert Line 2 to ATC by 2030 subject to the availability of funding.
Once ATC is activated, it would be possible to install platform screen doors as ATC would allow trains to stop at a precise position along the platform and line up train doors with platform doors. The cost to install platform doors at all stations on Lines 1, 2 and 4 could cost more than $1billion. Future lines, such as the Ontario Line could be built to operate with ATC and platform doors from the day of opening. The benefits of platform doors would be:
has been equipped with automatic train control from the outset, using the same SelTrac IS system as Vancouver's SkyTrain, meaning it could be operated autonomously. However, for safety reasons, each train has an operator on board who monitors the doors.

Light rail

When completed, Line 5 Eglinton will use Bombardier Transportation's Cityflo 650 CBTC automatic train control on the underground section of the line between Laird station and Mount Dennis station, along with the Eglinton Maintenance and Storage Facility adjacent to Mount Dennis station.

Track

Lines 1, 2 and 4the heavy-rail linesrun on tracks built to the Toronto gauge of, the same gauge used on the Toronto streetcar system. According to rail historians John F. Bromley and Jack May, the reason that the Yonge subway was built to the streetcar gauge was that between 1954 and 1965, subway bogies were maintained at the Hillcrest Complex, where the streetcar gauge was used for shop tracks. The Davisville Carhouse was not equipped to perform such heavy maintenance, and the bogies would be loaded onto a specially built track trailer for shipment between Davisville and Hillcrest. This practice ceased with the opening of the shops at the Greenwood Yard in 1965.
Line 3 Scarborough uses standard-gauge tracks, as the ICTS design for the line did not allow for the interchange of rail equipment between the subway system and Line 3. When its ICTS vehicles need anything more than basic service, they are carried by truck to the Greenwood Subway Yard.
The Line 5 Eglinton and Line 6 Finch West LRT lines will be constructed with standard-gauge tracks. The projects are receiving a large part of their funding from the Ontario provincial transit authority Metrolinx and, to ensure a better price for purchasing vehicles, it wanted to have a degree of commonality with other similar projects within Ontario.

Facilities

The subway system has the following yards to provide storage, maintenance and cleaning for rolling stock. All yards are located above ground.
FacilitiesYear
opened
Lines
served
Remarks
Davisville Yard1954
Greenwood Yard1966
Keele Yard1966Closed in 1978; reopened June 18, 2017
McCowan Yard1985
Wilson Yard1977
Eglinton 2022Under construction
Finch 2023Under construction

Safety

There are several safety systems for use by passengers in emergencies:
A trial program began in 2008 with Toronto EMS and has been expanded and made permanent, with paramedics on hand at several stations during peak hours: Spadina and Bloor–Yonge and Union and Eglinton

Training

Subway operators begin their training at Hillcrest with a virtual reality mockup of a Toronto Rocket car. The simulator consists of the operator cab with full functions, a door and partial interior of a subway car. The simulator is housed in a simulated subway tunnel. Construction of a new subway training centre is underway at the Wilson Complex, as part of the Toronto Rocket subway car program.

Expansion plans

Provincially supported projects

The Ontario Line is a proposed rapid transit line that has succeeded the Relief Line project. The proposed completion date for the project is 2027.
The Line 5 West Extension to Pearson Airport is a proposal to extend Line 5 Eglinton from its terminus at Mount Dennis Station west along Eglinton Avenue West to the proposed Pearson Transit Hub in Mississauga. In April 2019, Ontario premier Doug Ford said that he would commit funds for this proposal.
The Yonge North Subway Extension is a proposal to extend Line 1 Yonge–University north along Yonge Street from Finch station, the existing terminus of Line 1, to Richmond Hill. There would be new stations at Drewry/Cummer, Steeles Avenue, Clark Avenue, Royal Orchard Boulevard, Langstaff Road and the existing Richmond Hill Centre Terminal at Highway 7. The extension was proposed in the province's MoveOntario 2020 plan. The main problem with this proposal is that Line 1 is at capacity, and the TTC says that the Relief Line and SmartTrack must both be in service before opening the YNSE. The project is projected to be completed by 2030.
The Scarborough Subway Extension is a proposal to replace Line 3 Scarborough with an eastward extension of Line 2 Bloor–Danforth. On October 8, 2013, Toronto City Council conducted a debate on whether to replace Line 3 Scarborough with a light rail line or a subway extension. In 2014, the city council voted to extend Line 2 Bloor–Danforth to Scarborough City Centre, which would eventually lead to the closure of Line 3. The SSE would be long and add one new station to Line 2 at Scarborough Town Centre. TTC and city staff finalized the precise route of the SSE in early 2017. In 2019, the Government of Ontario proposed a modified version of the proposal now known as the Line 2 East Extension. The L2EE is now long and adds three new stations. The proposed completion deadline for the project is between 2029 and 2030.
The Line 4 East Extension to McCowan is a proposal to extend Line 4 Sheppard east along Sheppard Avenue East to McCowan Road, where it is set to link up with the Scarborough Subway Extension. Premier Doug Ford said in April 2019 that he would commit funds related to this proposal.

Other proposals

The Line 5 East Extension to Malvern is a proposal to extend Line 5 Eglinton east to Malvern. This proposal was originally part of the cancelled Scarborough–Malvern LRT in Transit City. It would have stations at Eglinton GO and Guildwood GO, as well as the University of Toronto Scarborough campus.
The Jane LRT is a proposed LRT line that would begin at Jane station on Line 2 and proceed north to Pioneer Village station on Line 1. While initially part of the cancelled Transit City plan, the Jane LRT is part of the 2018–2022 TTC Corporate Plan and tentatively referred to as Line 8.
The Line 4 West Extension to Sheppard West Station is a proposal that would extend Line 4 Sheppard west along Sheppard Avenue West to Sheppard West station, where it would link to Line 1 Yonge–University. It is currently listed as a "unfunded future rapid transportation project" in the City of Toronto's 2013 Feeling Congested? report.
The Line 6 East Extension to Finch Station is a proposal that would extend Line 6 Finch West east along Finch Avenue West to Finch Station, where it would link up with Line 1 Yonge–University. In March 2010, the Ontario government eliminated the proposed section of line between Finch West station and Finch station because of budget constraints. This section of the line was part of the original Transit City proposal. In 2013, this plan was revived as an "unfunded future rapid transit project" in the City of Toronto's Feeling Congested? report, meaning this extension may be constructed sometime in the future. The extension was later shown in the 2018–2022 TTC Corporate Plan with no timeline for completion.
Along with a proposal to extend Line 6 to Finch Station, there was another proposal that would have extended the line farther to Don Mills Station, where it would have provided a connection to Line 4 Sheppard. In May 2009, Metrolinx proposed that the line be extended from Finch station along Finch Avenue East and Don Mills Road into Don Mills station to connect with the Sheppard East LRT and create a seamless crosstown LRT line in northern Toronto to parallel the Eglinton Crosstown LRT in central Toronto. The TTC said that a planning study would have commenced in 2010.
The Line 6 West Extension to Pearson Airport is a proposal that would extend Line 6 Finch West west to Pearson Airport, where it would provide a link to Line 5 Eglinton. In 2009, the TTC studied the feasibility of potential routings for a future westward extension of the Etobicoke–Finch West LRT to the vicinity of the Woodbine Live development, Woodbine Mall, and Pearson International Airport. This extension was later reclassified as a future transit project as described in the 2013 Feeling Congested? report by the City of Toronto. Metrolinx revealed in January 2020 that they would study a possible connection to the Pearson Transit Hub at Pearson Airport.

Cancelled

The Queen subway line was a proposed subway line that would have been the city's second subway line. A roughed in station was built under Queen station. The route for the subway line is included in the proposed route for the Relief Line and the Ontario Line.
The Eglinton West line was a proposed subway line in the late 1980s and early 1990s. It was cancelled with the election of Mike Harris. Much of its route is included in Line 5 Eglinton.
One proposed expansion of Line 2 Bloor–Danforth into Mississauga included eight potential stations stretching west from Kipling Station to Square One Shopping Centre, retrofitting some existing GO Transit stations. The plan was for the subway stations to open in 2011. Mississauga mayor Hazel McCallion and the Regional Municipality of Peel did not support the project.
The Relief Line was a proposed heavy-rail subway line running from Pape station south to Queen Street East and then west to the vicinity of Toronto City Hall. The proposal includes intermediate stations at Sherbourne Street, Sumach Street, Broadview Avenue, and another near Gerrard Square. As of January 2016, alignment options and possible stations were still being studied, and the project is unfunded. Construction would take about 10 years to complete. As early as 2008, Metrolinx chair Rob MacIsaac expressed the intent of constructing the Relief Line to prevent overcrowding along Line 1. Toronto City Council also expressed support for this plan. In April 2019, the Government of Ontario under Doug Ford announced that the Ontario Line would be built instead of the Relief Line. As a result, TTC and City of Toronto staff suspended further planning work on the Relief Line in June 2019.

Transit City

The Sheppard East LRT was a proposed light rail line running east from Don Mills station to Morningside Avenue in Scarborough. The line was to be long with 25 surface stations and one underground connection at Don Mills station on Line 4 Sheppard. Construction of the Sheppard East LRT was to start upon completion of Line 6 Finch West. However, in July 2016, the Toronto Star reported the Sheppard LRT had been deferred indefinitely. In April 2019, Premier Doug Ford announced that the provincial government would extend Line 4 Sheppard to McCowan Road at some unspecified time in the future, replacing the proposed Sheppard East LRT.
The Don Mills LRT was a proposed LRT line that would have headed north from Pape station along Don Mills to Don Mills station. Its route was later incorporated into the Relief Line and Ontario Line proposals.
The Scarborough Malvern LRT was a proposed LRT line from Kennedy station east to the University of Toronto Scarborough. Its route was later incorporated into a proposed eastern expansion of Line 5 Eglinton.