As one of North America's largest and most high profile civil engineering endeavours, Ontario Power Generation's billion dollar, 11 1/2 km long tunnel will carry water from the Niagara River to the Sir Adam Beck Power Station. Bermingham Foundation Solutions was brought on board to construct a critical component of the project; one of the world's largest cofferdams.

For this project, the cofferdam was utilized to create a safe area for a tunnel boring machine to exit the completed tunnel. The cofferdam was designed to withstand the large volume of water as well as extreme stress from ice during the winter months while still being able to be quickly and efficiently removed once tunnel boring was completed. The cofferdam is of a cellular, gravity type design and consists of seven interlocked islands constructed on the bare rock.