Milliken Water Hardness & Quality Report (2026)

Milliken receives its water supply from the City of Markham Utilities, which is part of the larger Region of York water system. The primary source is Lake Ontario, with water drawn from the Lake Ontario watershed and treated at the Lake Ontario Water Treatment Plant located in Bellfontaine. In addition to this surface water, the supply is supplemented by groundwater drawn from local wells situated in the Oak Ridges Moraine area. These advanced treatment facilities provide water to over 200,000 residents and businesses throughout York Region, including Milliken itself.

The geology beneath Milliken significantly influences the water's composition. The region is underlain by Paleozoic bedrock, characterized by limestone and dolostone formations such as the Lockport and Salina Groups. As water interacts with these mineral-rich rocks, particularly through dissolution in shallow aquifers and runoff from the surrounding karst topography, it picks up dissolved calcium and magnesium ions. The Oak Ridges Moraine aquifer, which is recharged by precipitation filtering through glacial till and fractured bedrock, also contributes minerals to the groundwater component of the supply, resulting in a characteristically hard water profile for the area.

Homeowners in Milliken might notice the effects of this hard water on their appliances and plumbing. Scale buildup is common in pipes, water heaters, and kettles, which can decrease their efficiency and shorten their lifespan. You may also observe spotting on dishes after using the dishwasher, a stiff feel to laundered clothes, and drier skin after showering. Coffee makers and water heaters are particularly susceptible to damage. Simple measures like regular descaling with vinegar, installing drain screens, and using detergent boosters can help manage the issue. For a more comprehensive solution and to protect your appliances, installing a water softener is often recommended.