Ontario is currently building a lot. With more people moving in and a growing need for better roads, energy, hospitals, and schools, construction projects are popping up all over the province. In this article, you’ll learn about some of the biggest construction projects currently underway in Ontario, Canada, like the new Highway 413 and Canada’s first deep underground nuclear waste site.
Quick look
- Ontario ramps up infrastructure with over $180B in investments across transit, healthcare, energy, and education projects.
- Six major projects are underway, including the Highway 413, Ontario Line, a massive hospital redevelopment, and the first SMR in North America.
- Green energy gets a boost through projects like the Oneida battery system and major solar farms in Northern Ontario.
- What’s next: Ontario Place redevelopment, new schools, and more sustainable builds highlight the province’s future-focused strategy.
Project 1 – Highway 413
Photo courtesy of https://news.ontario.ca/
- Location: Greater Toronto Area (GTA)
- Size: 52 km highway with 11 interchanges, connecting Halton, Peel, and York regions
- Expected timeline: Construction begins in 2025
Highway 413 in Ontario is one of the biggest upcoming construction road projects. Once built, it will span 52 kilometers across the GTA and connect major areas, including Halton, Peel, and York. The goal is to help reduce traffic on other busy highways, like the 401 and 407, and make travel faster for drivers and transport trucks.
The province says Highway 413 will save commuters up to 30 minutes a trip. But not everyone agrees with the project. Some people are worried about the highway’s impact on farmland, wetlands, and the environment. To help with this, the Ontario government is conducting additional environmental studies and planning ways to mitigate damage to green spaces.
The project will also include new carpool lanes and connections to other major highways. It is expected to create thousands of jobs during construction and bring long-term benefits to growing communities in the area.
Project 2 – Canada’s Nuclear Waste Deep Geological Repository
Photo courtesy of https://zionlights.substack.com/
- Location: South Bruce, Ontario
- Size: Underground facility spanning 1,500 feet below the surface
- Expected timeline: Project in approval and design phase; construction planned for the late 2020s
One of the biggest energy construction projects in Ontario is being lead by the Nuclear Waste Management Organization (NWMO). The NWMO is planning to build the country’s first deep geological repository in South Bruce, Ontario. It will be used to safely store used nuclear fuel deep underground, where it won’t harm people or the environment.
The facility will be constructed approximately 1,500 feet underground in solid rock. The plan is to seal the waste in special containers and place them inside tunnels carved by robotic machines. These barriers are designed to keep the waste safely locked away for up to 1 million years.
Currently, the NWMO is collaborating with the community, conducting safety tests, and developing the design. If approved, this project would be one of the safest and most advanced nuclear waste facilities in the world. It’s also an important step toward making Canada’s energy system more sustainable.
Project 3 – Darlington New Nuclear (SMR) Project
Photo courtesy of
- Location: Darlington, Ontario
- Size: First commercial grid-scale Small Modular Reactor (SMR) in North America
- Expected timeline: Construction approved; completion expected in the early 2030s
Ontario is leading the way in clean energy with the Darlington New Nuclear Project. This project is managed by Ontario Power Generation (OPG) and will be the first grid-scale Small Modular Reactor (SMR) in North America.
The new reactor, known as the GE Hitachi BWRX-300, is designed to be smaller and faster to construct than traditional nuclear power plants. Although it occupies less space, it will still generate enough electricity to power approximately 300,000 homes.
The goal is to provide clean, reliable energy while helping the province meet its climate goals. The Darlington site is already home to a nuclear station, so it’s a good fit for this kind of upgrade. The project is also expected to create new jobs and support innovation in Canada’s growing nuclear sector.
Project 4 – Ontario Line Subway Extension
Photo courtesy of https://news.ontario.ca/
- Location: Toronto, Ontario
- Size: 15.6 km subway line with 15 stations
- Expected timeline: Completion by 2031
The Ontario Line is one of the biggest transit construction projects Toronto has ever seen. It will stretch 15.6 kilometers across the city and include 15 new stations. The goal is to give people faster and easier ways to get around, especially in busy downtown areas.
This project is a key part of Metrolinx’s plan to improve public transportation. It will help reduce crowding on the existing Line 1 by providing an alternative route through the city. When completed, the Ontario Line is expected to transport approximately 388,000 riders daily.
The new line will include underground tunnels, elevated tracks, and modern driverless trains. It will connect with other TTC, GO Transit, and streetcar lines, making it easier for people to get where they need to go. With construction already underway, the Ontario Line is poised to transform the way people move around Toronto.
Project 5 – Trillium Health Partners Mississauga Hospital Redevelopment
Photo courtesy of https://trilliumhealthworks.ca/
- Location: Mississauga, Ontario
- Size: 24-storey, over 2.8 million square foot hospital
- Expected timeline: Scheduled for completion by 2032
Trillium Health Partners is building a brand-new Mississauga Hospital, and it’s set to become the largest hospital in Canada. The new facility, named the Peter Gilgan Mississauga Hospital, will be over 2.8 million square feet in size and feature 24 floors, making it one of the most advanced healthcare buildings in the country.
Once completed, the hospital will offer over 950 beds, along with new trauma and surgery centers. It’s being built to meet the growing healthcare needs of Mississauga and the wider GTA West area. This project is part of a larger initiative to enhance hospital care and reduce wait times throughout Ontario.
The new hospital will also be built with the future in mind. It features eco-friendly elements such as green roofs, energy-saving systems, and smart technology, which enhance patient care and building performance. Construction has already started, and the hospital is expected to open its doors in 2032.
Project 6 – Oneida Energy Storage Project
Photo courtesy of https://www.oneidaenergystorage.ca/
- Location: Haldimand County, Ontario
- Size: 250 MW / 1,000 MWh battery storage system
- Expected timeline: Operational by 2025
The Oneida Energy Storage Project is one of the largest battery storage systems in Canada. It’s being built in Haldimand County and is designed to store and release clean energy when the power grid needs it most. This helps keep the electricity system stable, especially during peak times or when demand is high.
The project is a partnership between NRStor Inc. and the Six Nations of the Grand River Development Corporation, with support from Northland Power and the Canada Infrastructure Bank. It is an excellent example of Indigenous leadership in Canada’s energy future.
When complete, the system will be able to power thousands of homes and support more renewable energy sources, such as wind and solar, by storing excess electricity and sending it back to the grid when needed. It’s expected to be up and running by 2025.
Is Ontario spending more on infrastructure this year?
Yes, Ontario is making a major push to improve its infrastructure with several major construction projects. Through the Build Ontario Plan, the province has committed to spending over $180 billion over the next decade. This money will go toward building new roads, hospitals, schools, and transit systems.
In 2024, the government confirmed that most of this funding will be allocated to three key areas: transportation, healthcare, and education. These are the sectors that will help support a growing population and make life easier for people across the province.
To facilitate the development of these large builds more quickly and efficiently, Ontario is also collaborating with private companies. These public-private partnerships help share the cost and speed up construction timelines.
Some of the biggest projects, like the Ontario Line, Highway 413, and the Mississauga Hospital redevelopment, are all part of this plan. These builds are designed to address long-term needs, such as increased traffic, aging infrastructure, and rising demand for healthcare services.
What’s breaking ground next?
Ontario is gearing up for more big projects, with several getting ready to start soon. These builds focus on green energy, schools, nuclear power, and public spaces, all contributing to a more resilient province.
Ontario Place redevelopment
The Ontario Place site is getting a big makeover that includes new public parks, walking trails, and waterfront access. This redevelopment is led by Infrastructure Ontario, in partnership with the Ministry of Tourism, Culture and Sport. There’s also a wellness resort in the works by Therme Canada, featuring indoor pools, walking trails, and public beach areas.
New schools in Peel and Durham
To support growing communities, the province of Ontario is investing in new school construction. One example is the new Caledon East Public School, which was funded in 2025 to accommodate more students in the area. The province is also providing billions in capital funding for school and childcare infrastructure across Peel and Durham regions.
Major solar farms in Northern Ontario
Ontario is adding more clean energy to the grid. One major project is the Nanticoke Solar Facility, situated on the site of a former coal plant and partly owned by OPG and the local First Nations. There’s also the Sault Ste. Marie Solar Park, a long-operational solar farm that continues to provide green power.
Subscribe to our newsletter for exclusive updates on Canada’s most significant construction and infrastructure projects.
