Dorval Water Hardness & Quality Report (2026)

The City of Dorval Water Utility supplies the municipality of Dorval, Quebec. Its water originates from the St. Lawrence River, where it is drawn and then treated at the Dorval Water Treatment Plant. This facility is one of two in the Montreal area that also includes fluoride addition to the supply. The utility operates within the larger Montreal water management system, serving residential, commercial, and industrial customers throughout Dorval's roughly 13 square kilometers. The vast St. Lawrence River watershed collects drainage from the Great Lakes and Ottawa River systems before reaching Dorval's intake.

The local geology is primarily characterized by Ordovician-age sedimentary rocks, specifically limestones and dolomites found within the St. Lawrence Lowlands. These rock types are rich in minerals, which dissolve into the water, giving it a moderately hard quality. Overlaying this bedrock are glacial till and Champlain Sea clays, which can affect how water infiltrates the ground and exchanges ions. Additionally, urban runoff from upstream areas adds further complexity to the river's chemical composition before it reaches the treatment plant.

This moderately hard water can lead to some limescale buildup in appliances like kettles, dishwashers, and water heaters, potentially reducing their efficiency and increasing energy consumption over time. You might also notice laundry feeling a bit stiffer, and soaps may not lather as effectively, possibly requiring more detergent for cleaning. Regularly descaling appliances and fixtures with vinegar is a good practice; for those concerned about hard water's impact, installing a water softener is recommended to help prolong appliance life and improve overall cleaning performance.