St. Andrew-Windfields Water Hardness & Quality Report (2026)

Residents of St. Andrew-Windfields in North York, part of the City of Toronto, receive their municipal water from the City of Toronto Water Division. This supply originates from Lake Ontario and is treated at the R.C. Harris Water Treatment Plant before being distributed through the North York corridor. The utility serves a vast population of over 2.8 million people across Toronto, employing extensive filtration and disinfection methods to meet stringent provincial and federal regulations. The water drawn from the Lake Ontario watershed, which extends across New York, Ontario, and Quebec, is shaped by the underlying bedrock's carbonate formations and glacial deposits.

The geological landscape beneath the Lake Ontario watershed is characterized by Paleozoic carbonate rocks, including limestone and dolostone. Formations such as the Queenston Formation and Georgian Bay Formation lie within the lake basin. These sedimentary strata, along with regional aquifers and glacial till, contribute dissolved minerals like calcium and magnesium to the water. This geological influence is typical of the Great Lakes region, resulting in a consistently hard water supply without being overly corrosive.

Homeowners in St. Andrew-Windfields will likely notice significant limescale buildup on pipes, kettles, water heaters, washing machines, and dishwashers. This scale not only reduces the efficiency and lifespan of appliances, potentially increasing energy costs by up to 31%, but can also lead to reduced heating performance and frequent clogs. Periodic descaling with vinegar or specialized devices can help manage the issue. To effectively mitigate scale, improve soap lathering, and protect household plumbing systems, installing a water softener is strongly recommended. While the water is safe for consumption and meets all Health Canada and Ontario standards, the high mineral content may influence its taste.