42 reasons Ontario dominated this year’s Top 100 projects list

Ontario’s infrastructure landscape has reached a historic fever pitch in 2026. According to the latest ReNew Canada Top 100 Projects report, the province is the primary engine behind a record-breaking $343 billion national investment in public assets. Ontario currently hosts 42 of the top 100 projects, including the top eight most expensive developments in the country. This dominance is driven by a massive nuclear renaissance and a multi-billion dollar transit revolution aimed at supporting a rapidly growing population.

Here is a closer look at the heavy hitters shaping the province today.

Pickering Generating Station Refurbishment – $26.8 Billion

The top-ranked project in Canada involves a massive life-extension of the Pickering “B” nuclear units. After receiving the official go-ahead from the province, Ontario Power Generation is moving into the execution phase to overhaul four CANDU reactors. This project is expected to create over 30,000 jobs during its peak and provide reliable, low-carbon power for another 30-plus years. The project team includes Ontario Power Generation as the owner, with engineering and procurement support from partners like AtkinsRéalis and Aecon, and turbine work provided by Siemens Energy.

Darlington New Nuclear Project – $20.9 Billion

This project marks the first deployment of grid-scale Small Modular Reactors (SMRs) in the G7. Located in Clarington, the plan involves constructing four BWRX-300 units to meet the province’s rising demand for electrification. By 2026, excavation for the first unit’s reactor building is nearly complete, with the project serving as a global blueprint for next-generation nuclear technology. This initiative is a collaboration between Ontario Power Generation and a powerhouse consortium including GE Hitachi Nuclear Energy, Aecon, and AtkinsRéalis.

GO Expansion – On-Corridor Works – $15.7 Billion

As the largest transit project in Ontario’s history, this initiative aims to transform the regional rail network into a frequent, all-day system with service every 15 minutes. The scope includes electrifying over 600 kilometres of track and upgrading signalling systems across the Greater Golden Horseshoe. The project is being delivered by Metrolinx and Infrastructure Ontario through a progressive partnership with the ONxpress Transportation Partners consortium, which comprises Aecon, Alstom, FCC Construcción, and Deutsche Bahn.

Peter Gilgan Mississauga Hospital – $14.0 Billion

Construction is well underway for what will become the largest hospital in Canada. This 2.8-million-square-foot facility will triple the capacity of the current Mississauga Hospital, featuring a 22-storey patient care tower and one of the busiest emergency departments in the province. The project is being managed by Infrastructure Ontario and Trillium Health Partners. The design and construction are led by the ED+PCL Healthcare Partners consortium, which includes EllisDon, PCL Constructors, and a design team featuring Parkin Architects and Adamson Associates.

Bruce Power Refurbishment – $13.0 Billion

Bruce Power continues its multi-decade campaign to refurbish six of its eight nuclear units in Tiverton. This major component replacement program ensures that the site remains one of the world’s largest sources of clean energy through 2064. By early 2026, the team has successfully completed work on several units and is applying lessons learned to the remaining reactors. The project is a private-sector-led effort by Bruce Power, utilizing the Shoreline Power Group—a joint venture between Aecon, AtkinsRéalis, and United Engineers & Constructors.

Darlington Nuclear Refurbishment – $12.8 Billion

In a major win for the province, the decade-long overhaul of all four existing Darlington reactors was completed in early 2026. The project finished four months ahead of schedule and $150 million under budget, proving that large-scale nuclear projects can be executed with precision. This massive undertaking was led by Ontario Power Generation alongside its primary partners, AtkinsRéalis and Aecon, employing over 6,000 workers at the peak of construction.

Ontario Line – $11.0 Billion

The Ontario Line is a 15.6-kilometre standalone subway line that will connect Exhibition Place to the Ontario Science Centre. Designed to relieve congestion on the existing TTC subway network, the project features 15 stations and connects to dozens of other transit routes. It is currently in a high-intensity construction phase involving multiple contracts. Key participants include Metrolinx and Infrastructure Ontario, with major work being handled by the Connect 6ix consortium and the Ontario Transit Group, featuring companies like Plenary Americas, Hitachi Rail, and Ferrovial.

GO Expansion – Early Works – $10.5 Billion

This category encompasses the hundreds of smaller, essential preparatory projects required before the main electrification of the GO network can occur. This includes grade separations, bridge expansions, and station renovations across the entire GTHA. Metrolinx manages these works through a wide array of contractors including Graham, EllisDon, and Kiewit, ensuring the corridor is ready for high-speed, electrified rail service.

TTC Vehicles Program – $7.2 Billion

This ongoing program focuses on the procurement and maintenance of the Toronto Transit Commission’s fleet, including new subway cars, streetcars, and zero-emission buses. A major priority in 2026 is the replacement of the aging Line 2 Bloor-Danforth subway trains. The program is managed by the TTC and the City of Toronto, with primary vehicle manufacturing and support provided by Alstom and Nova Bus.

Hazel McCallion LRT – $5.6 Billion

Formerly known as the Hurontario LRT, this 18-kilometre line will run through Mississauga and Brampton. By early 2026, the project has entered the final testing and commissioning phase for the light rail vehicles. The project is delivered by Metrolinx and Infrastructure Ontario under a P3 agreement with the Mobilinx consortium, which includes John Laing, Astaldi, Hitachi, and EllisDon.

Yonge-North Subway Extension – $5.6 Billion

This project extends the TTC’s Line 1 subway nearly eight kilometres from Finch Station north into Richmond Hill, Markham, and Vaughan. It is a critical link for connecting York Region to the downtown Toronto core. The project is a collaboration between Metrolinx and Infrastructure Ontario, with early works and tunneling supported by teams like STRABAG and the Crosslinx consortium.

Scarborough Subway Extension – $5.5 Billion

Replacing the retired Scarborough RT, this project extends Line 2 by 7.8 kilometres further into Scarborough with three new stations. Tunneling is a major focus in 2026, with the massive tunnel boring machine making steady progress. The project is led by Metrolinx and Infrastructure Ontario, with the primary tunneling contract awarded to the STRABAG team and station work involving the Scarborough Transit Connect joint venture of Aecon and FCC.

Centre Block Rehabilitation Project – $5 Billion

This is the largest and most complex heritage restoration ever undertaken in Canada. The project involves a complete overhaul of the iconic Centre Block on Parliament Hill, including masonry restoration, the replacement of all primary building systems, and the construction of a new underground Parliament Welcome Centre. As of early 2026, the project has reached several structural milestones, including significant progress on the new foundation and the installation of complex scaffolding around the Peace Tower. Public Services and Procurement Canada is the project owner, with a massive joint venture between PCL Constructors and EllisDon leading the construction management.

Eglinton Crosstown West Extension – $4.7 Billion

This project extends the soon-to-open Eglinton Crosstown LRT an additional 9.2 kilometres from Mount Dennis to Renforth Drive. The extension will run primarily underground and provide a critical link toward Pearson International Airport. By early 2026, tunneling is a major focus, with the second of two tunneling contracts currently active. The project is a collaboration between Metrolinx and Infrastructure Ontario, with the West End Connectors consortium (comprising Aecon, Dragados, and Ghella) and STRABAG playing central roles in the tunneling and civil works.

Ottawa LRT – Stage 2 – $4.7 Billion

Stage 2 is a massive expansion of Ottawa’s O-Train network, adding 44 kilometres of new rail and 24 new stations to the East, West, and South. In 2026, the project is nearing its final milestones, with the East Extension toward Orléans entering its trial running phase. This expansion is managed by the City of Ottawa, with construction being handled by the East-West Connectors (Kiewit and Eurovia) and the TransitNEXT team (SNC-Lavalin/AtkinsRéalis) for the Trillium Line portion.

ALTO (High-Speed Rail Network – Ontario Segment) – $4.3 Billion

Now officially transitioned from “High Frequency” to “High Speed” Rail, this project aims to revolutionize travel between Toronto, Ottawa, and Quebec City. The Ontario segment specifically focuses on the corridor connecting Toronto to Ottawa via Peterborough. In early 2026, the project is in a high-intensity “Co-Development” phase, with the project office—known as Alto—partnering with the Cadence consortium (including CDPQ Infra, AtkinsRéalis, and Air Canada) to finalize the route alignment and station locations.

Accelerated High-Speed Internet Program – $3.9 Billion

This province-wide initiative is designed to ensure that every home and business in Ontario has access to reliable, high-speed internet by the end of 2026. The program uses an innovative “reverse auction” model to award contracts to internet service providers who can deploy fiber-optic or high-speed wireless technology to underserved rural and remote areas. The project is led by Infrastructure Ontario and the Ministry of Infrastructure, with a wide range of providers like Bell, Rogers, and various regional cooperatives executing the physical rollouts.

South Niagara Hospital – $3.6 Billion

Designed as Canada’s first fully electric hospital, the South Niagara Hospital is a 1.3-million-square-foot facility focused on seniors’ care and complex health needs. By early 2026, the project celebrated the final structural concrete pour for its 12-storey superstructure. Infrastructure Ontario and Niagara Health are the owners, with the EllisDon Infrastructure Healthcare team leading the design, build, and long-term maintenance of the facility.

Hamilton LRT – $3.4 Billion

The Hamilton LRT is a 14-kilometre transit project that will run from McMaster University through the downtown core to Eastgate Square. After years of planning, 2026 marks a significant uptick in on-the-ground activity, specifically focusing on utility relocations and preparatory civil works along King Street. The project is a joint effort between Metrolinx, Infrastructure Ontario, and the City of Ottawa, with major civil contracts being managed by a variety of national and international engineering firms.

Don River and Central Waterfront & Connected Projects – $3.0 Billion

This multi-year environmental project is designed to clean up Toronto’s waterways by upgrading the city’s aging sewer system. The centerpiece is a 22-kilometre tunnel system that will capture and store combined sewer overflows during heavy rain. In 2026, work is focused on the Inner Harbour West Tunnel and the massive integrated pumping station at the Ashbridges Bay Treatment Plant. The City of Toronto leads the project, supported by contractors such as STRABAG and the Black & McDonald/Aecon joint venture.

Energy Services Modernization (Ottawa) – $3 Billion

Part of the Energy Services Acquisition Program (ESAP), this project is modernizing the district energy system that heats and cools over 80 federal buildings in the National Capital Region. The shift involves converting the old steam-based system to a more efficient low-temperature hot water network. By early 2026, several new energy centers are operational, and the project is nearing substantial completion. Public Services and Procurement Canada is the owner, partnering with the Innovate Energy consortium (including PCL, PCL Solutions, and Black & McDonald).

The Ottawa Hospital New Campus Development – $2.8 Billion

Located near Dow’s Lake, this project will create one of the most technologically advanced research hospitals in North America. Construction in 2026 is centered on the completion of the massive parking garage facility and the commencement of foundation work for the main acute care hospital towers. The project is led by The Ottawa Hospital and Infrastructure Ontario, with the development team including PCL Constructors and various design partners.

New Hospital for Sick Children (SickKids) – $2.4 Billion

Known as Project Horizon, this massive campus redevelopment aims to replace aging infrastructure with a new patient care tower and support facilities. In 2026, the focus has shifted toward the early phases of the Peter Gilgan Family Patient Care Tower following the successful completion of the Patient Support Centre. This project is a collaboration between The Hospital for Sick Children and Infrastructure Ontario, with PCL Constructors serving as a primary construction partner.

F.G. Gardiner Expressway Strategic Rehabilitation – $2.2 Billion

This project involves the complex, phased rehabilitation of Toronto’s elevated expressway to extend its service life. By early 2026, work is focused on the accelerated completion of the section between Dufferin Street and Strachan Avenue, with crews working to restore bridge decks and replace structural steel. The City of Toronto manages the plan, with Aecon Group serving as a lead contractor for major segments of the rehabilitation.

50. Weeneebayko Area Health Authority (WAHA) Redevelopment – $1.8 Billion

This project replaces aging health facilities in the James Bay region with a new hospital and elder care center in Moosonee, plus a new ambulatory care center on Moose Factory Island. In 2026, construction is active at the Moosonee site, overcoming significant logistical challenges to bring modern healthcare to Northern Ontario. Infrastructure Ontario and WAHA are the lead partners, with Pomerleau heading the design and build.

SmartTrack Stations Program – $1.7 Billion

This program adds five new transit stations to the existing GO rail network within the City of Toronto to provide more frequent, subway-like service. By 2026, construction is well underway at sites like Liberty Village and St. Clair-Old Weston, with stations reaching substantial completion. This is a joint initiative between the City of Toronto, Metrolinx, and Infrastructure Ontario, with construction led by partners like Graham Construction.

Place du Portage III Renewal – $1.6 Billion

This federal project involves the complete modernization of the Place du Portage III complex in the National Capital Region. The renewal includes a new building envelope, updated mechanical systems, and modernized workspaces for thousands of federal employees. By 2026, the project is in a heavy interior renovation phase. Public Services and Procurement Canada oversees the project, with construction management provided by various joint venture partners.

CAMH Phase 1D Redevelopment – $1.6 Billion

The final phase of the CAMH master plan involves constructing two new buildings on the Queen Street West site: the Discovery Centre and the Secure Care and Recovery Building. In early 2026, construction is focused on the vertical rise of these structures following the completion of deep foundation work. Infrastructure Ontario and the Centre for Addiction and Mental Health lead the project, with PCL Constructors serving as the builder.

Macdonald Block Reconstruction Project – $1.5 Billion

This project is the comprehensive reconstruction of the four towers and podium that make up Ontario’s primary government office complex in Toronto. By early 2026, the project has moved into the final commissioning and occupancy phase as staff begin to move back into the modernized, energy-efficient spaces. Infrastructure Ontario delivered this through a P3 model with the Fengate/PCL Progress Partners consortium.

Bloor-Yonge Station Capacity Improvements – $1.5 Billion

To address overcrowding at the TTC’s busiest interchange, this project is expanding the northbound and southbound platforms and adding a second platform for eastbound passengers. In 2026, the project is in a high-intensity excavation phase beneath the existing station. The TTC and City of Toronto lead the work, with the contract awarded to a progressive design-build team led by various international engineering firms.

Dwyer Hill Training Centre Modernization – $1.4 Billion

This high-security project involves the modernization and expansion of the training facility for the Canadian Special Operations Forces. Work in 2026 includes the construction of specialized training structures and new administrative buildings. The Department of National Defence is the owner, with construction managed by various specialized defense contractors and overseen by Defence Construction Canada.

Port Hope Area Initiative – $1.3 Billion

This is a massive environmental remediation project focused on the safe, long-term management of historic low-level radioactive waste in Port Hope and Clarington. In 2026, work continues with the excavation of waste from local sites and its transportation to the newly built long-term waste management facility. The project is managed by Canadian Nuclear Laboratories on behalf of Atomic Energy of Canada Limited.

Gilgan Family Queensway Health Centre – $1.3 Billion

Part of the Trillium Health Partners expansion, this project is building a new nine-storey patient tower in Etobicoke dedicated to complex care and rehabilitation. By 2026, the project reached a major milestone with the raising of the final structural beam. Infrastructure Ontario and Trillium Health Partners are the owners, with EllisDon Corporation handling the design, build, and finance.

Thunder Bay Correctional Complex – $1.2 Billion

This project builds a new 345-bed, state-of-the-art correctional facility to replace the aging Thunder Bay Jail and Correctional Centre. Construction in 2026 is focused on the interior fit-out and security systems, with a target opening for the fall. Infrastructure Ontario and the Ministry of the Solicitor General lead the project, with EllisDon Infrastructure Justice serving as the project lead.

Waasigan Transmission Line – $1.2 Billion

This critical energy project involves the construction of a new double-circuit transmission line from Thunder Bay to Atikokan and a single-circuit line from Atikokan to Dryden. In 2026, crews are focused on tower assembly and stringing along the cleared right-of-way. The project is a partnership between Hydro One and several First Nation partners through the Gwayakocchigun LP consortium.

Toronto Western Hospital Patient Tower – $1.1 Billion

UHN is building a new 15-storey surgical and patient care tower at the Toronto Western site to increase surgical capacity and modernize patient rooms. By 2026, the exterior facade of the tower is nearing completion. Infrastructure Ontario and University Health Network lead the project, with PCL Constructors handling the construction.

West Memorial Building Rehabilitation – $1.0 Billion

This project involves the heritage restoration of the West Memorial Building in Ottawa to serve as the temporary home of the Supreme Court of Canada. In 2026, work is focused on the final interior finishes and the restoration of heritage masonry. Public Services and Procurement Canada is the owner, with various heritage specialized contractors leading the restoration.

TerraCanada National Capital Region – $1.0 Billion

This project builds new, state-of-the-art science facilities to support collaborative research into sustainable land and resource development. In 2026, early construction is active on the specialized laboratory facilities. The project is part of the Laboratories Canada program, overseen by Public Services and Procurement Canada in collaboration with various federal science departments.

GO Kitchener Extension – $959 Million

This extension involves significant infrastructure upgrades along the Kitchener GO line, including new tracks and bridge expansions, to support two-way, all-day service. By 2026, several key bridge structures have been completed, and work is focused on final signaling upgrades. Metrolinx and Infrastructure Ontario lead the project, working with various rail construction partners.

CFB Trenton – Main Operating Base – $850 Million

This project involves a series of infrastructure upgrades at 8 Wing Trenton to support the arrival of new aircraft fleets, including the CC-330 Husky. Work in 2026 includes the construction of new hangars and apron expansions. The Department of National Defence is the owner, with work overseen by Defence Construction Canada.

Advanced Nuclear Materials Research Centre – $800 Million

Located at the Chalk River Laboratories, this will be Canada’s largest nuclear research facility, supporting the life-extension of the existing reactor fleet and the development of SMRs. In early 2026, the facility is fully enclosed and interior laboratory fit-out is underway. Canadian Nuclear Laboratories leads the project on behalf of Atomic Energy of Canada Limited.

Ontario Public Safety Radio Network – $765 Million

This project replaces the province’s aging radio network with a modern, encrypted land mobile radio system for first responders. By early 2026, the network is nearing full operational status with most towers migrated to the new P25 standard. The Ministry of the Solicitor General leads the project, with Bell Mobility serving as the primary delivery partner.

Bowmanville Extension Project – $730 Million

This project extends the Lakeshore East GO line by nearly 20 kilometres to Bowmanville, adding four new stations. In 2026, construction has officially broken ground, with early work focused on track bed preparation and utility relocations. Metrolinx and Infrastructure Ontario are the owners, with the major construction contract awarded to a team including Aecon and Kiewit.