Ontario Moves Forward with Highway 401 Expansion in Oshawa

Province kicks off key infrastructure upgrades in Oshawa, replacing overpasses to pave the way for a future 10-lane Highway 401 aimed at easing congestion and boosting the local economy.

Oshawa, ON — Ontario’s Ministry of Transportation is moving ahead with a major infrastructure upgrade in Oshawa as part of its long-term plan to widen Highway 401 to 10 lanes through the Durham Region. The province announced that it will replace the Park Road and Cubert Street overpasses — a critical step in preparing for future lane expansions that aim to reduce gridlock and support economic growth.

The project is part of Ontario’s nearly $30 billion investment in highways, roads, and bridges across the province.

“Replacing Highway 401 overpasses in Oshawa is a critical step in our plan to widen the 401 so we can tackle gridlock, grow our economy, and support the drivers and businesses who rely on this highway every day,” said Ric Bresee, Parliamentary Assistant to the Minister of Transportation.

Construction Work Underway

The construction contract has been awarded to Dufferin Construction Company, a division of CRH Canada Group Inc. based in Oakville. The project includes:

• Replacing the Park Road and Cubert Street overpasses in Oshawa

• Resurfacing eastbound lanes of Highway 401 between Harmony Road and Courtice Road

These upgrades will accommodate the future expansion of Highway 401 to 10 lanes, addressing the growing demand on one of the busiest transportation corridors in the country.

Boosting Jobs and the Local Economy

Officials say the project will support hundreds of well-paying jobs in construction, engineering, and the supply chain. Oshawa Mayor Dan Carter praised the project as a long-term investment in the city’s economic future.

“The replacement of the Park Road and Cubert Street overpasses is more than just infrastructure — it’s a strategic investment in our city’s future,” said Mayor Carter. “This project will help support local businesses, create good-paying jobs, and strengthen our economy as a whole.”

A Broader Plan to Relieve Gridlock

Highway 401 is vital to Ontario’s transportation network, with more than 10,000 trucks transporting $380 million in goods daily. Reducing congestion is a key goal of the expansion project.

“Reducing gridlock on the 401 is essential for families and businesses in Whitby and across Durham Region,” said Whitby MPP Lorne Coe. “This project will not only improve daily commutes but also help create a future of better roads and stronger communities.”

Durham MPP Todd McCarthy and Pickering—Uxbridge MPP Peter Bethlenfalvy also voiced strong support, highlighting the project’s role in modernizing aging infrastructure, improving commute times, and bolstering Ontario’s economy amid increasing trade pressures and U.S. tariffs.

The Big Picture

According to a report by the Canadian Centre for Economic Analysis, traffic gridlock costs Ontario’s economy up to $56 billion each year — a figure that could climb to $108 billion by 2044 if left unaddressed.

As part of Ontario’s broader strategy to protect and grow its economy, the Highway 401 upgrades in Oshawa are a tangible sign of the province’s commitment to long-term infrastructure renewal, regional mobility, and economic resilience.

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