Construction of a retention structure to reduce overflows during heavy rainfall (Ouvrage St-Thomas)

pre-construction

A retention structure allows for the temporary storage of wastewater during very heavy rainfalls in order to avoid a backflow into the network or a discharge into the natural environment. This project consists of the construction of a 15,000 m³ retention structure in the Griffintown sector, more precisely in the quadrilateral between William, Ottawa, St-Thomas and du Séminaire streets. The site chosen for the implementation of the retention basin allows an optimal control of overflows and ensures a better hydraulic protection for the residents of the sector. This structure will be built in an area of approximately 500 hectares of downtown Montreal that is undergoing development and densification of its occupation.