Platteville Water Hardness & Quality Report (2026)

The City of Platteville Public Works Department, operating as Platteville Waterworks, supplies roughly 12,000 residents in Grant County, Wisconsin. Their entire water supply comes from deep groundwater wells, tapping into the region's extensive aquifer systems without any surface water sources. Water is treated at the city's water treatment facility on N Bonson St, where it undergoes disinfection and other essential processing to meet stringent state and federal drinking water regulations. The water originates from local recharge areas within the Driftless Region, part of the Upper Mississippi River Basin watershed.

The groundwater originates from deep sandstone formations, specifically the Cambrian Jordan Sandstone Aquifer and associated dolomitic limestones from the Prairie du Chien Group. These Paleozoic rock layers, dating back to the Ordovician and Cambrian periods, are naturally rich in calcium and magnesium. As water percolates through the fractured, karst-influenced bedrock of the Driftless Area, these minerals dissolve, resulting in a characteristically hard water supply typical of the region's groundwater geology.

Homeowners will likely notice scale buildup in appliances and on fixtures due to the water's mineral content. This hardness accelerates wear on water heaters, dishwashers, and washing machines, and it reduces the effectiveness of soaps and detergents. You might also see spots on glassware after washing. To protect your plumbing and appliances, a water softener is strongly recommended. Regular maintenance of your softener, including proper regeneration cycles, will help mitigate these issues and extend the lifespan of your household equipment. The water is generally safe, with the utility complying with EPA standards, though past tests have shown some contaminants exceeding health guidelines, likely natural minerals.