Newmarket Water Hardness & Quality Report (2026)

The Town of Newmarket Water Utility, part of York Region, provides water to about 90,000 people in Newmarket and nearby York County, Ontario, Canada. Their supply comes from two main places: local groundwater wells that tap into underground aquifers, and the York-Durham Sewerage System, which draws water from Lake Ontario. This Lake Ontario water is treated at the Lake Ontario Water Treatment Plant in Ajax before being sent to Newmarket. The town's public works department manages the distribution of this blended water supply.

The region's water flows through bedrock formed in the Paleozoic era, including limestone and dolostone. Specifically, the Oak Ridges Moraine area has groundwater interacting with these carbonate rocks, such as the Queenston Formation and Georgian Bay Formation. Even the Lake Ontario supply picks up minerals from runoff that has touched the Niagara Escarpment, known for its dolomitic limestones. All this contact with mineral-rich rocks dissolves calcium and magnesium, making the water hard.

Dealing with hard water means you'll likely notice scale buildup in your pipes, kettles, and especially in your water heater and dishwasher. This buildup makes appliances less efficient and can shorten their lifespan. You might also find that soap doesn't lather as well in the shower, and your laundry may not come out as bright. To combat these effects, homeowners often resort to regular descaling with vinegar, particularly for coffee makers and kettles. For most residents in Newmarket, installing a water softener is the most effective solution to prevent scale and extend the life of plumbing fixtures and appliances.