Dam Design and Construction

BC Hydro’s Site C earthfill dam complete

The earthfill dam stands about 60 meters tall, stretches more than one kilometer across the Peace River, and is about 500 meters wide at its base.
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BC Hydro’s Site C earthfill dam complete

BC Hydro has reached a major milestone on its 1.1 GW Site C hydropower project with the completion of the earthfill dam.

The earthfill dam stands about 60 m tall, stretches more than 1 km across the Peace River, and is about 500 m wide at its base.

The Site C project is being built and designed in accordance with international and Canadian safety practices to withstand a major (one in 10,000 years) earthquake.

The placement of material for the Site C earthfill dam began in 2021. In total, about 16 million m3 of earthfill material were placed.

Most of the material for the earthfill dam was taken directly from the dam site, while other material was sourced locally offsite and transported to the dam on a 5-km-long conveyor belt.

With the earthfill dam complete, the next steps involve capping it and building roads across for crews to travel on once the project comes into operation.

Completion of the earthfill dam is one of the essential milestones required before filling the Site C reservoir. While BC Hydro is targeting to begin reservoir filling in fall 2023, there are still a number of key project areas that need to be completed. These areas include the approach channel, spillways, tailrace area, dam intake structures and certain components of the powerhouse.

Another key component for reservoir filling is the conversion of one of the tunnels that currently divert the Peace River around the project site. This process requires the installation of constrictions (or large ring-shaped devices) inside one of the tunnels to restrict the flow of water. This work is now underway.

In August 2022, The Province of British Columbia, BC Hydro, the country of Canada reached a partial settlement in a lawsuit filed by the West Moberly First Nations. The settlement provides the West Moberly First Nations with financial benefits, contracting opportunities, the transfer of provincial Crown lands and jointly developed recommendations for land management measures over provincial Crown lands, among other benefits. The remainder of the civil suit, in which West Moberly First Nations has asserted that the existing hydroelectric dams on the Peace River and the cumulative impacts of resource development in their territory are an infringement of their Treaty rights, was moved to confidential government-to-government discussions to resolve the remaining matters.

Construction on the Site C project began on July 27, 2015. The project remains on-track to have all six generating units in-service by 2025.