AtkinsRéalis tasked with $1.7B hydropower upgrade in Quebec

Key Takeaways:

• AtkinsRéalis has secured a seven-year, $1.7 billion contract from Rio Tinto to refurbish the Isle-Maligne hydropower plant in Alma, Quebec. The project includes replacing eight of the plant’s 12 turbine-alternator units and upgrading major structural and mechanical systems.
• The refurbishment aims to extend the plant’s operational life for decades, aligning with AtkinsRéalis’ commitment to sustainability and its century-long expertise in delivering complex hydropower projects.
• The project continues a long-standing partnership between AtkinsRéalis and Rio Tinto, with a focus on collaboration, safety, and community empowerment as part of advancing a low-carbon economy in the region.

The Whole Story:

AtkinsRéalis Group announced today that it has been awarded a seven-year contract by Rio Tinto for the refurbishment of the Isle-Maligne hydropower plant in Alma, Quebec. AtkinsRéalis will provide execution engineering, integrated procurement, and construction management services to extend the hydropower plant’s operational life for decades to come.

“We’ve specialized in executing large-scale hydropower projects for over a century and the life extension work on this historic hydropower plant will be guided by our commitment to sustainability and our purpose—to engineer a better future for our planet and its people,” said Ian L. Edwards, President and CEO of AtkinsRéalis.

Commissioned in 1926 as the world’s largest hydropower plant, Isle-Maligne is set to undergo a $1.7 billion comprehensive refurbishment. AtkinsRéalis’ cross-regional teams will use cutting-edge technologies and best practices to replace eight of the 12 turbine-alternator groups and upgrade corresponding water passages, along with the architectural, structural, electrical, and mechanical elements of the balance of the plant.

“Our long-standing partnership with Rio Tinto is based on effective collaboration and our proven ability to work and deliver on complex, high-impact projects.” said Stéphanie Vaillancourt, President, Canada, AtkinsRéalis. “Collaboration, excellence, resilience and health-safety will be the driving forces behind our work on this project. These principles are essential for empowering the surrounding communities and advancing the development of a low-carbon economy.”

Past hydropower plant refurbishment mandates by AtkinsRéalis include the Rio Tinto’s Shipshaw Expansion Project, OPG’s Calabogie Redevelopment project, and BC Hydro’s John Hart Generating Station Replacement project.

Conceived by U.S. industrialist James B. Duke—who bought the Saguenay River water rights in 1913—the Isle-Maligne hydro project broke ground in 1923. Engineers first pushed a 24-km rail spur through the bush to supply the remote island site, then battled the river with ingenious winter methods: brush-boom ice platforms let them install cofferdams, more than 337 000 m³ of steam-heated concrete were poured from a trestle into a 216 m-long, 45 m-high powerhouse-dam, and a dramatic 100-ton dynamite blast in early 1925 diverted the Saguenay so the final spillway could close.

The first Francis unit spun on 24 April 1925; by year-end eight (ultimately twelve) turbines delivered 402 MW, making Isle-Maligne the world’s largest hydro station when it was fully commissioned in 1926 and tied by high-voltage lines to the newborn Arvida aluminium complex and Quebec City.