Antioch Water Hardness & Quality Report (2026)

The Antioch Municipal Water Company draws its water from underground sources serving the village of Antioch in Lake County, Illinois. This public water supply comes from multiple wells that tap into local sand and gravel aquifers, as well as bedrock aquifers. Disinfection is performed with chlorination at wellhead facilities, as there isn't a central treatment plant or surface water intake. The utility's service area spans about 8 square miles around the village, near the Wisconsin border. The groundwater originates from the Lake Michigan watershed's influence zone, being recharged by precipitation that seeps through glacial deposits and fractured bedrock in the Des Plaines River sub-basin.

Key geological features include Quaternary glacial drift lying atop Silurian dolomites and limestones from the Racine and Waubakee units. These highly soluble carbonate rocks are the main reason Antioch's water is hard. As these rocks dissolve naturally, they release minerals like magnesium and calcium, giving the groundwater a high mineral content, more so than surface water sources. The glacial till and outwash deposits also contribute minerals leached from sedimentary layers, typical for this region's groundwater.

Homeowners in Antioch will likely notice scale buildup in appliances like hot water heaters, dishwashers, and washing machines, which can decrease their efficiency and lifespan. You might also see white deposits on faucets and other fixtures, and find that soap doesn't lather as well. Spotting on dishes after washing is another common sign. Regularly descaling appliances with vinegar can help, but installing a whole-house water softener is often recommended to combat these issues and protect your plumbing. Recent reports flagged the tap water with a D grade due to 43 violations, though no contaminants exceed EPA legal limits. Concerns include detectable levels of chlorodibromoacetic acid, m-Xylene, and p-Cresol.