Chilliwack Water Hardness & Quality Report (2026)

The City of Chilliwack Water Utility supplies drinking water to its residents using a groundwater-dominant system. The vast majority of the water, 99.93%, is drawn from the Sardis-Vedder Aquifer, with a small 0.07% contribution from the Marble Hill Aquifer. These aquifers are tapped via ten wells, eight serving the Sardis-Vedder Aquifer and two the Marble Hill Aquifer. No surface water reservoirs or rivers are part of the supply. While specific treatment plants aren't named, the Chilliwack water undergoes extensive monitoring both before and after treatment, with over 40 sampling points across wells and distribution networks.

The Chilliwack water originates from the Sardis-Vedder Aquifer and Marble Hill Aquifer, both situated within the Fraser Valley region. These aquifers are composed of Quaternary alluvial and glacial deposits, including layers of sand, gravel, and silt, which overlie Tertiary sedimentary rocks. The surrounding mountainous terrain, particularly the Cascade Mountains, contributes limestone-derived minerals and calcareous sediments to the groundwater. This geological makeup, rich in carbonate-rich sediments, leaches elevated levels of calcium and magnesium ions, resulting in a notably hard water supply for the community.

Households in Chilliwack may notice scale buildup in appliances like pipes, water heaters, and dishwashers, which can reduce their efficiency and lifespan. Kettles and faucets might develop white mineral deposits. Washing machines and boilers, in particular, may require more detergent and energy to operate effectively. To manage these effects, regular descaling with vinegar, installing drain screens, and considering a water softener are often recommended. Softening the water can also improve soap lathering and reduce staining on fixtures. The utility confirms that source water meets standards, with extensive monitoring for contaminants and disinfection as part of standard groundwater treatment processes.