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A Lower Mattagami project construction site.

Lower Mattagami River Project

Northern Ontario's largest hydroelectric project in 50 years was completed safely, on time and on budget in January 2015.

See how we did it, with the support of our partners and Ontario communities.

Project facts

6 New units

At four redeveloped stations

438 Megawatts

Of new hydro capacity

$2.6 Billion

Investment in Northern Ontario

25% Equity

For partner Moose Cree First Nation

More efficiency for Ontario

The $2.6 billion Lower Mattagami Project has allowed Ontario Power Generation to produce more clean, renewable electricity from new generating units. These units were added to each of our existing Little Long, Harmon and Kipling stations, and complement a brand new three-unit station at our Smoky Falls facility.

These six new units on the Lower Mattagami River added 438 megawatts of greenhouse gas-free electricity; enough capacity to meet nearly three times the peak demand of Thunder Bay.

Change in station capacity

StationPrevious capacityCapacity addedTotal
Little Long 138 MW 67 MW 205 MW
Harmon 142 MW 78 MW 220 MW
Kipling 154 MW 78 MW 232 MW
Smoky Falls 52 MW 215 MW 267 MW
TOTAL 486 MW 438 MW 924 MW

Partnering with the Moose Cree of Ontario

Throughout 25 years of planning, much of the project’s success is attributable to the unique partnership Ontario Power Generation achieved with Moose Cree First Nation.

Under the Amisk-oo-Skow Agreement, the Moose Cree received a 25% equity stake in the project. Since a typical hydro station remains in service for 90 years or more, the Moose Cree community has a revenue stream they can count on for many years.

The agreement also provided valuable training and employment opportunities, helping to rejuvenate the Moose Cree community with a much-needed economic boost.

Moose Cree businesses were awarded over $300 million worth of project contracts and at peak construction periods, the project employed over 250 Indigenous workers.

OPG is proud to consider the Moose Cree a vital community partner in our project.

Our generation on Lower Mattagmi River