Hudson Water Hardness & Quality Report (2026)

The Hudson Waterworks utility supplies drinking water to about 14,000 residents in the City of Hudson, St. Croix County, Wisconsin. This supply comes from groundwater wells that draw from regional aquifers, with treatment occurring at the city's water treatment facility. The 2025 Annual Water Quality Report indicates full compliance with federal standards, as confirmed by recent sampling. The watershed is part of the St. Croix River basin, and Hudson's groundwater is recharged by precipitation seeping into the Willow River sub-basin and nearby glacial till.

The underground geology comprises Cambrian-Ordovician sandstone aquifers covered by Paleozoic limestone and shale. These layers naturally leach minerals into the water, giving it a very hard character. This mineral-rich profile is typical of the karst-influenced terrain, where fractures facilitate ion exchange without significant surface runoff. The Upper Midwest driftless area geology, with its glacial drift over fractured bedrock, also plays a role in dissolving minerals like calcium and magnesium from carbonate and evaporitic formations.

Homeowners in Hudson will likely notice substantial scale buildup in appliances such as pipes, water heaters, dishwashers, and coffee makers. This accumulation can reduce their efficiency and shorten their lifespan. You might also find laundry feels stiff and that soap doesn't lather well, often necessitating the use of more detergent. To combat these mineral deposits and improve the water's usability, regular maintenance like deliming appliances and flushing systems is advised. Installing a whole-house water softener is strongly recommended for most households. The utility confirms safe pH levels within EPA ranges and full compliance for lead and copper.