Sainte-Marie draws municipal drinking water from Rivière Chaudière (permanent intake; two submerged screens ~2.4 m depth at 1065 rue Notre-Dame Sud), treated at Installation de production Sainte-Marie (X2134730).
Ask where Sainte-Marie drinking water begins and the answer is Rivière Chaudière (permanent intake; two submerged screens ~2.4 m depth at 1065 rue Notre-Dame Sud), then Installation de production Sainte-Marie (X2134730). That supply chain is what the water atlas puts beside hardness and lead.
City vulnerability report (2026): screening, coagulation/flocculation, sedimentation, ozonation, UV reactors, then chlorine gas disinfection and caustic soda pH adjustment. Feeds Saint-Joseph and Bisson reservoirs. MELCC lists chlorination, filtration, ozonation, and ultraviolet.
See the Sainte-Marie water page for the grade, source notes, and municipal report links.