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Construction progressing on Little Long Dam Safety project in northeast

In northeast Ontario, work is progressing on the Little Long Dam Safety project, which will improve dam safety on the Mattagami River in the event of extreme weather events.

In northeast Ontario, north of Kapuskasing, construction is progressing on the Little Long Dam Safety project to improve dam safety on the Mattagami River.
In northeast Ontario, north of Kapuskasing, construction is progressing on the Little Long Dam Safety project to improve dam safety on the Mattagami River.

Once major construction is completed by the end of 2023, the project will increase the discharge capacity at the eight-gate Adam Creek spillway structure located on the Little Long Reservoir, about 90 kilometres north of Kapuskasing.

This work will ensure extreme floodwater can safely bypass OPG’s four Lower Mattagami River stations – Little Long, Smoky Falls, Harmon and Kipling generating stations – in the event of large-scale flooding in the area. It also helps OPG comply with updated dam safety requirements established by the Province of Ontario.

“The project will strengthen our infrastructure in the area to ensure public safety and the safety of the environment, while helping our hydro stations continue to operate safely and efficiently,” said Ahmad Al-Ali, Project Manager with OPG.

A key action in OPG’s new Climate Change Plan is adaptation, which includes strengthening the company’s operations and infrastructure to be resilient against climate-related impacts. The plan also highlights continued investment in OPG’s hydro operations as an important part of becoming a net-zero carbon company by 2040.

Downstream drilling
Drilling takes place on a downstream plunge pool at the Adam Creek spillway site.

In addition to protecting the community and environment, the project is providing a number of employment and contracting opportunities for nearby residents in Kapuskasing and Smooth Rock Falls, as well as Indigenous businesses and communities like Moose Cree First Nation, whose homeland territory hosts the work site.

A total of 46 Indigenous workers have been hired on by the main contractor, Kiewit, as of February 2021. That includes Violet Montgomery, a Moose Cree member who is working as an Environmental Technician. Members from the Taykwa Tagamou Nation are also helping support the project.

It is estimated that a total of $32 million in contracts will be awarded to Indigenous and local businesses throughout the project. Currently, 100 per cent of the project’s contractor vendors are from Canada, with more than 75 per cent from Ontario.

More about the project

At the Adam Creek spillway, a total of four new sluicegates will be added to increase the structure’s discharge capacity. These sliding barriers are used by dam operators to control water levels and flows in rivers.

Other reliability improvements include replacing the eight existing sluicegates at Adam Creek and two existing sluicegates at the Little Long Main Dam. Their associated hoist superstructures will also be replaced.

An overhead shot of the Adam Creek spillway.
An overhead shot of the Adam Creek spillway.

Major construction activities for 2021 include continued rock blasting and excavation to complete a downstream plunge pool that will dissipate energy from the water flowing through the spillway and reduce the potential for localized erosion.

In total, five of the 10 existing sluicegates at the site are set to be replaced this year.

Due to its remote area, a work camp has been established to house staff and contractors. Even as temperatures dipped to -30 degrees Celsius in the northeast this winter, the project’s 150 on-site staff forged ahead while maintaining COVID-19 protocols. Heaters and pumps helped to prevent equipment from freezing during the coldest days.