The Government of Ontario has confirmed the commencement of tunnelling on the Ontario Line, marking the first subway tunnel excavation in downtown Toronto in more than 60 years and representing one of the most significant construction milestones in the city’s transit history. Two tunnel boring machines (TBMs), named Libby and Corkie following a public naming contest, are now operating from Exhibition Station, excavating twin tunnels heading eastward toward the Don Yard near the Don Valley Parkway and Lakeshore Boulevard. The tunnels will reach depths of up to 40 metres below the surface, boring through stable bedrock that the province says will minimise noise and vibration impacts on surrounding areas.

At the Don Yard, trains will emerge from the tunnels and continue above ground across the Lower Don Bridge. The TBMs are expected to advance at an average rate of between 17 and 20 metres per day. When complete, the Ontario Line will span 15.6 kilometres from Exhibition Place westward to the Eglinton Crosstown Light Rail Transit line at Don Mills Road, serving 15 stations and offering more than 40 connections to existing bus, streetcar, light rail and regional rail services. The line is projected to carry close to 390,000 to 400,000 daily passenger journeys and is designed to bring approximately 230,000 more people within walking distance of rapid transit.

The tunnelling milestone arrives against a backdrop of a project that has grown enormously in scope and cost since it was first announced by the Ford government in 2019 with an estimated price tag of CAD 10.9 billion. The current overall cost of the Ontario Line stands at approximately CAD 29.5 billion, according to the latest Metrolinx update, representing a cost trajectory that mirrors the experience of comparable urban rapid transit projects across North America. The Eglinton Crosstown West Extension (ECWE) in Toronto, which has faced major schedule and delivery pressures similar to the original Eglinton Crosstown LRT, further highlights the challenges of tunnelling, utility relocation, and systems integration in a dense urban corridor under complex procurement structures. What the Ontario Line is attempting to do differently, at least structurally, is to separate the civil works from the rolling stock and systems contracts, distributing risk across distinct procurement packages rather than embedding it all in a single consortium.

The South Civil package held by Ontario Transit Group at CAD 6.1 billion is the largest single contract in the programme, and the commencement of TBM operations under that contract is the clearest signal yet that the project’s civil infrastructure is tracking. That said, the overall completion timeline has already shifted, with Metrolinx CEO Michael Lindsay confirming the line now targets the early 2030s rather than the previously stated 2031 opening. For a city where Line 1 crowding between Bloor-Yonge and Wellesley is already at a level that frustrates daily commuters, every year of delay carries a real cost in congestion and capacity, and the pressure on the construction team is correspondingly high.

Tunnelling Scope, Station Progress and System-Wide Construction Status

Twin tunnels being excavated by TBMs Libby and Corkie, launching from Exhibition Station portal

Tunnel depth: up to 40 metres below ground, through stable bedrock

Tunnel length (south segment): approximately 6 kilometres from Exhibition Station to Don Yard portal, west of the Don River

Average TBM advance rate: 17 to 20 metres per day

Trains will emerge above ground at the Don Yard and cross the Lower Don Bridge heading eastward

Exhibition Station: major construction underway, including platforms, escalators, elevators, two north entrances, one south entrance, and an underground traction power substation; forecast peak usage of more than 12,000 passengers per period, including over 6,000 GO Transit-to-Ontario-Line transfers

Station excavation complete: King West, Moss Park, Distillery District, Chinatown

Second tunnel launch shaft broken ground at Gerrard Station to support the northern segment’s separate tunnelling works beneath Pape Avenue

Stations with active works across the full 15.6-kilometre alignment

Project Fact Sheet

Project Name: Ontario Line Subway (Southern Civil, Stations and Tunnel Package — and overall line)

Line Length: 15.6 kilometres

Route: Exhibition Place to Don Mills Road (Eglinton Crosstown LRT connection)

Number of Stations: 15, including six interchange stations

Transit Connections: More than 40 connections to bus, streetcar, LRT and regional rail services

Overall Project Cost: CAD 29.5 billion (including capital and operational costs)

South Civil Contract Value: CAD 6.1 billion (CAD 5.6 billion capital; CAD 0.5 billion financing and transaction costs)

Contract Type: Design-build-finance (P3, fixed price)

Tunnel Depth: Up to 40 metres

South Tunnel Length: approximately 6 kilometres (Exhibition Station to Don Yard portal)

TBM Names: Libby and Corkie

TBM Advance Rate: 17 to 20 metres per day (average)

Projected Daily Ridership: approximately 390,000 to 400,000 passenger journeys

Peak Hour Crowding Reduction (Line 1): up to 15% reduction on the busiest stretch between Bloor-Yonge and Wellesley

Travel Time Improvement: end-to-end journey reduced from approximately 70 minutes to under 30 minutes

Projected Completion: Early 2030s

Federal Contribution: More than CAD 4 billion

Programme Context: Part of a CAD 70 billion provincial transit investment plan, alongside Scarborough Subway Extension, Eglinton Crosstown West Extension and Yonge North Subway Extension

Line Announced: 2019

Project Team

Owner/Client: Province of Ontario (Government of Ontario)

Programme Delivery Authority: Metrolinx — Crown agency responsible for delivering the Ontario Line and the broader provincial transit expansion programme

CEO, Metrolinx: Michael Lindsay

Procurement and Contracting Authority: Infrastructure Ontario (IO) — delivered the South Civil package through its Public-Private Partnership (P3) model

South Civil Design-Build-Finance Contractor: Ontario Transit Group (OTG) — joint venture between Ferrovial Construction Canada Inc. (50%) and VINCI Construction Grands Projets (50%), with VINCI operating through its subsidiary Janin Atlas Inc.

Construction Leads (South Civil): Ferrovial Construction and Janin Atlas Inc.

Design Consultants (South Civil): AECOM Canada, COWI North America, GHD Limited, SENER Group

https://www.group.sener/en/Fairness Monitor: Independent third-party monitor overseeing the competitive procurement process

Provincial Political Leadership: Premier Doug Ford; Minister of Transportation Prabmeet Sarkaria; Acting Infrastructure Minister Todd McCarthy

City of Toronto: Mayor Olivia Chow — attended provincial press conference marking the tunnelling commencement milestone