Mount Olive-Silverstone-Jamestown Water Hardness & Quality Report (2026)

The Mount Olive-Silverstone-Jamestown neighbourhood, part of Toronto, Ontario, relies on Toronto Water for its supply. The primary source is Lake Ontario, with water treated at the R.C. Harris and R.L. Clark Water Treatment Plants. While Lake Ontario is the main origin, a small amount of groundwater also contributes to the supply. This treated water reaches over 2.8 million residents across the Greater Toronto Area through a vast network of reservoirs and pumping stations.

The water's journey begins in the Lake Ontario watershed, which includes the Niagara Escarpment and Ordovician limestone and shale formations within the Simcoe Basin. As water flows over and through these carbonate-rich Paleozoic rocks, it picks up dissolved minerals. This prolonged contact, especially with dolomitic limestones, naturally leads to the high mineral content and characteristic hardness found in most municipal water supplies throughout the GTA.

Homeowners in this area often notice the effects of this hard water, such as limescale buildup in appliances like dishwashers and water heaters, which can reduce their efficiency and lifespan. You might also see crusty deposits on faucets and kettles, and soap scum can accumulate on fixtures. To combat these issues, regularly descaling with vinegar is a good practice. Many residents find that installing a whole-house water softener is the most effective way to mitigate the problems associated with hard water and prolong the life of their plumbing and appliances. Toronto Water appliances. Toronto Water does maintain a pH between 7.5-8.5 for corrosion control.