Mr. Jean-Louis Servranckx reports

AECON JOINT VENTURE FINALIZES CONTRACT FOR THE HOWARD A. HANSON DAM FACILITY PROJECT IN WASHINGTON STATE

The FlatironDragados-Aecon Group Inc. joint venture, composed of Aecon (40 per cent) and FlatironDragados (60 per cent), has finalized a $691-million (U.S.) contract with the U.S. Army Corps of Engineers for the Howard A. Hanson dam additional water storage fish passage facility project in Washington State. Aecon's share of the contract will be added to its construction segment backlog in the first quarter of 2026.

The project is being delivered under an integrated design and construction contract model. Completion of the collaborative development phase and the commencement of construction are expected in the second quarter of 2026, with anticipated completion in the third quarter of 2031.

The project involves the construction of a downstream dam facility that will consist of vertically stacked ports on the dam's upstream side. The downstream facility will work in conjunction with elements upstream of the dam, supporting connections to spawning habitat.

"This project is an exciting undertaking that leverages Aecon's extensive civil and dam infrastructure capabilities while advancing Aecon's steady growth across North America," said Jean-Louis Servranckx, president and chief executive officer, Aecon. "Building on the collaborative development phase, we are well positioned to safely execute construction, working alongside our client, tribal partners, federal and state agencies, and Tacoma public utilities."

"We are excited to start construction on the additional water storage project at Howard A. Hanson dam," said USACE Seattle district Cdr. Col. Kathryn Sanborn. "Howard A. Hanson dam serves as our primary line of defence against catastrophic flooding in the Green River Valley, holding a record pool and decreasing peak flood by over five feet during the record-breaking flows in December, 2025. This project significantly expands our water storage, ensuring a reliable supply for thousands of homes and supporting the future economic growth of the region, while also providing salmon access to nearly half of the Green River habitat above the dam."

Further information about the project is available on the U.S. Army Corps of Engineers website.

About Aecon Group Inc.

Aecon is a North American construction and infrastructure development company with global experience. Aecon delivers integrated solutions to private and public sector clients through its construction segment in the civil, urban transportation, nuclear, utility and industrial sectors, and provides project development, financing, investment, management, and operations and maintenance services through its concessions segment.

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