Peace River Hydro Partners (PRHP) has reached a major milestone at the Site C dam project in British Columbia, Canada, with completion of the two Peace River diversion tunnels. Work has also been completed on four gate structures, located at the upstream and downstream entrances of both tunnels.

This work was completed during a period of scaled back activity on the project due to the COVID-19 pandemic, with BC Hydro prioritising work required to achieve river diversion in fall 2020.

The tunnels, Located on the north bank of the river, the tunnels are approximately 750m long and 11m in diameter. They will be used later this year to reroute the Peace River around the dam site, allowing for the construction of the earthfill dam across the main river channel.

Excavations on the tunnels began in summer 2018 and were completed in late 2019. The tunnel lining process, which involved using a custom-built slip form to enable concrete to cure in a perfect circle, began in summer 2019 and was completed in May 2020.

The Site C Clean Energy Project is the third dam and hydroelectric generating station being built on the Peace River in northeast British Columbia. It is also the largest energy infrastructure project currently in the works across Canada. The project will supply 1100MW of capacity, and produce nearly 5100GWh of electricity annually.

PRHP was awarded the $1.75 billion main civil works contract in December 2015. Its partners include ACCIONA Infrastructure Canada Inc., Petrowest Corporation and Samsung C&T Canada Ltd.