Villeray–Saint-Michel–Parc-Extension Water Hardness & Quality Report (2026)

Villeray–Saint-Michel–Parc-Extension receives its drinking water through Ville de Montréal — Direction de l'eau potable, supplied from the same integrated municipal network as all Montréal boroughs — drawing from the St. Lawrence River and Rivière des Prairies via the Atwater, DesBaillets, and Charles-J. Des Baillets water treatment plants. Treatment uses ozonation, biofiltration, UV disinfection, and chloramination, meeting all Guidelines for Canadian Drinking Water Quality (GCDWQ) standards. Hardness in this borough's distribution zone is 72.5 mg/L (4.2 gpg) — classified as moderately hard by Health Canada, comparable to the adjacent Rosemont–La Petite-Patrie borough to the south.

Like neighbouring Rosemont, this northern Montréal borough is served from a distribution zone sourced predominantly from the Rivière des Prairies intake at the Charles-J. Des Baillets treatment plant. The Rivière des Prairies draws from upstream Laurentian catchments where Precambrian Shield granite and gneiss tributaries contribute soft, low-mineral water that dilutes the harder Ordovician limestone-influenced St. Lawrence base flow, reducing hardness across north-central Montréal's distribution network to the 72–73 mg/L range.

At 72.5 mg/L, Villeray–Saint-Michel–Parc-Extension residents experience only light scale deposits on kettle elements and tap connections — descaling two to three times a year is sufficient. Hot water tanks in this borough perform at a moderate efficiency level without dedicated treatment, and annual flushing is generally adequate maintenance. The borough's dense pre-war and post-war housing stock includes many buildings with original plumbing; Montréal's Direction de l'eau potable advises residents in older properties to request water quality testing for lead, in compliance with Health Canada guidelines for drinking water quality.