This 23.2 MW hydroelectric project on the Sainte-Anne River involved the construction of a concrete spillway of 9 m high by 45 m long, five cofferdams, a water intake, a tunnel 440 m long and 4.5 m wide, and a power plant.
In addition, the construction of a 4,000 m2 floor nail wall was required to allow the construction of the permanent access road to the plant.
Our engineers were responsible for producing the detailed engineering of all the structures, as well as the technical support during the work. The project won the Grand Prix du génie-conseil québécois in the “Energy” category in 2018, awarded by the Association des firmes de génie-conseil.
Main Challenges
The project is located in a high seismic area near a known geotechnical fault (Cap Tourmente).
The powerhouse had to be located at the bottom of a steep canyon, which required unusual retaining wall construction option using soil nails.
A fault is going through the riverbed, which forced the redesign of a section of the concrete dam and the construction of a cut-off wall.
The project is located near a recreational park, and structural elements had to be designed and positioned to blend in and be as invisible as possible to maintain the integrity of the park.