The Denis St. Pierre Water Pollution Control Plant, originally built in 1977, was experiencing several issues associated with an aging facility - the capacity was regularly being overwhelmed and the plant was no longer meeting rated flow requirements or Ministry of Environment effluent compliance limits. Our team set out to design improvements that not only improved capacity issues, but changed the treatment process from Sequencing Batch Reactor (SBR) to extended aerated activated sludge (EAAS) which provides a more robust treatment process and is easier to operate.
Completing the design presented the design team with a huge number of challenges. Creativity was needed at every point in the design process in an effort to reuse existing facilities whenever possible in order to minimize costs. We also needed to design and schedule the construction around a plant that needed to remain in operation throughout the improvement process. Where possible, our team used gravity to their advantage to push flow through the plant, thus reducing the overall number of pumps required in the design.