Lower Mattagami River Project

Kapuskasing, Ontario

The Lower Mattagami River Project is an investment into clean, renewable energy. It was the largest hydroelectric power generation initiative in nearly 40 years in Northern Ontario. Ontario Power Generation selected Kiewit-Alarie Partnership to design and build the project.

This project retired the old 52-megawatt Smoky Falls Generating Station and constructed a new 271-megawatt station immediately adjacent to the existing plant. In addition, a new generating unit was added to three other power generating stations along the Mattagami River: Little Long, Kipling and Harmon.

The project required the excavation of 650,000 cubic meters of overburden and over 700,000 cubic meters of rock, as well as the placement of over 190,000 cubic meters of concrete over five years.

Foundations work included a 5,050-square-foot cut-off wall to support construction to repair and replace four hydroelectric generating stations.

The project increased Ontario’s energy generation capacity by over 440 megawatts, enough electricity to power up to 440,000 additional homes.