Water hardness in Wisconsin, characterized by the amount of dissolved minerals such as calcium and magnesium, can considerably vary throughout the state due to its diverse geological landscapes. Positioned in the Midwestern region of the U.S., Wisconsin’s water hardness levels reflect its range of geological features.
Across Wisconsin, water hardness can span from moderately soft to notably hard, contingent on the geology of the area and the source of the water supply. For example, areas situated over the Cambrian-Ordovician aquifer may have softer water, attributed to the rapid movement of water through less mineral-rich sediments. Conversely, regions with harder water usually lie underneath limestone and other mineral-laden formations like those found in the Niagara Escarpment, leading to greater concentrations of dissolved minerals.
The variation in water hardness throughout Wisconsin influences not only the taste and aesthetics of the water but also the efficiency of soaps and detergents, plumbing maintenance, and the durability of appliances that use water. Given the state’s significant geological diversity, water hardness is not uniform, emphasizing the need for localized water treatment solutions and continuous monitoring of water quality.
Upon reviewing the data, it’s evident that water hardness levels vary greatly in different cities across Wisconsin, USA. Specific data isn’t available for most locations. Among the cities for which data is reported, the highest water hardness level is seen in Germantown, Hartland, and Grafton with a hardness ppm of 393.7 and a hardness gpg of 23.0. In contrast, the city with the lowest recorded water hardness level is Fox Crossing, reporting a hardness ppm of 35.0 and a hardness gpg of 2.0.
City | Hardness ppm (mg/L) | Hardness gpg | Information Source | Notes |
Milwaukee | 130.0 | 7.6 | Link | Doesn’t report hardness, but sells to West Allis which reports hardness |
Madison | n/a | n/a | Link | |
Green Bay | n/a | n/a | Link | |
Kenosha | 137.0 | 8.0 | Link | |
Racine | 140 | 8.2 | Link | Lake Michigan |
Appleton | n/a | n/a | Link | |
Waukesha | n/a | n/a | Link | |
Eau Claire | n/a | n/a | Link | |
Oshkosh | n/a | n/a | Link | |
Janesville | n/a | n/a | Link | |
West Allis | 130.0 | 7.6 | Link | Purchases from Milwaukee |
La Crosse | n/a | n/a | Link | |
Sheboygan | 146.0 | 8.5 | Link | |
Wauwatosa | 130.0 | 7.6 | Link | Purchases from Milwaukee |
Fond du Lac | n/a | n/a | Link | |
Brookfield | n/a | n/a | Link | |
New Berlin | 130.0 | 7.6 | Link | Purchases from Milwaukee |
Wausau | n/a | n/a | Link | |
Menomonee Falls | 130.0 | 7.6 | Link | Purchases from Milwaukee |
Greenfield | 130.0 | 7.6 | Link | Covered by Milwaukee |
Franklin | n/a | n/a | Link | |
Beloit | 340.0 | 19.9 | Link | |
Oak Creek | n/a | n/a | Link | Lake Michigan |
Sun Prairie | n/a | n/a | Link | |
Manitowoc | n/a | n/a | Link | |
West Bend | n/a | n/a | Link | |
Fitchburg | n/a | n/a | Link | |
Mount Pleasant | 140 | 8.2 | Link | Gets from Racine |
Neenah | n/a | n/a | Link | |
Superior | n/a | n/a | Link | Lake Superior |
Stevens Point | n/a | n/a | Link | |
De Pere | n/a | n/a | Link | |
Muskego | n/a | n/a | Link | |
Caledonia | 140 | 8.2 | Link | Purchases from Racine |
Mequon | 130.0 | 7.6 | Link | Purchases from Milwaukee |
Watertown | n/a | n/a | Link | |
Middleton | n/a | n/a | Link | |
Pleasant Prairie | 137.0 | 8.0 | Link | Purchases from Kenosha |
Germantown | 393.7 | 23.0 | Link | |
South Milwaukee | n/a | n/a | Link | LAke Michigan, but separate facility from Milwaukee. Doesn’t report hardness but likely in the 130s range based on Milwaukee and Kenosha reports |
Howard | n/a | n/a | Link | Purchases some from Lake Michigan, but doesn’t indicate how much |
Fox Crossing | 35.0 | 2.0 | Link | |
Onalaska | 376.6 | 22.0 | Link | |
Marshfield | n/a | n/a | Link | |
Wisconsin Rapids | n/a | n/a | Link | |
Oconomowoc | 317.0 | 18.5 | Link | |
Menasha | n/a | n/a | Link | |
Cudahy | n/a | n/a | Link | Lake Michigan |
Kaukauna | n/a | n/a | Link | |
Ashwaubenon | n/a | n/a | Link | Purchases from Green Bay |
Menomonie | n/a | n/a | Link | |
Beaver Dam | n/a | n/a | Link | |
River Falls | n/a | n/a | Link | |
Bellevue | n/a | n/a | Link | Purchases from Manitowoc |
Pewaukee | n/a | n/a | Link | |
Hartford | n/a | n/a | Link | |
Weston | n/a | n/a | Link | |
Hudson | 210.0 | 12.5 | Link | |
Waunakee | n/a | n/a | Link | |
Chippewa Falls | n/a | n/a | Link | |
Whitefish Bay | n/a | n/a | Link | |
Greendale | 130.0 | 7.6 | Link | Purchases from Milwaukee |
Salem Lakes | n/a | n/a | Link | No online CCR, may purchase from Kenosha but isn’t clear |
Whitewater | n/a | n/a | Link | |
Verona | n/a | n/a | Link | |
Allouez | n/a | n/a | Link | Purchases from Manitowoc |
Plover | n/a | n/a | Link | |
Shorewood | n/a | n/a | Link | |
Harrison | n/a | n/a | Link | Purchases from Appleton |
Glendale | n/a | n/a | Link | |
Stoughton | 308.1 | 18.0 | Link | |
Suamico | n/a | n/a | Link | |
Brown Deer | 130.0 | 7.6 | Link | Purchases from Milwaukee |
Port Washington | n/a | n/a | Link | Lake Michigan |
Fort Atkinson | n/a | n/a | Link | |
Cedarburg | n/a | n/a | Link | |
Baraboo | 248.0 | 14.5 | Link | Took system average |
Grafton | 376.6 | 22.0 | Link | |
Little Chute | n/a | n/a | Link | |
Richfield | n/a | n/a | Link | Looks like Richfield uses mostly private wells, per CCR lookup on EPA website |
Platteville | n/a | n/a | Link | |
Sussex | n/a | n/a | Link | |
Waupun | 85.6 | 5.0 | Link | Treated down to 5 gpg by city |
Oregon | 331.0 | 18.3 | Link | |
Two Rivers | n/a | n/a | Link | |
Marinette | n/a | n/a | Link | Lake Michigan |
Burlington | n/a | n/a | Link | |
Holmen | n/a | n/a | Link | |
DeForest | n/a | n/a | Link | |
Monroe | n/a | n/a | Link | |
Hobart | n/a | n/a | Link | Purchases from Green Bay |
New Richmond | n/a | n/a | Link | |
Elkhorn | n/a | n/a | Link | |
Portage | n/a | n/a | Link | |
Reedsburg | 160.0 | 9.3 | Link | |
Sparta | n/a | n/a | Link | |
Sturgeon Bay | n/a | n/a | Link | |
Hartland | 393.7 | 23.0 | Link | |
Tomah | n/a | n/a | Link | |
St. Francis | n/a | n/a | Link | No online CCR, but probably covered by Milwaukee, based on Google Maps. |
ppm = Parts Per Million
mg/L = Milligrams Per Liter
gpg = Grains Per Gallon
Hard water can cause issues such as mineral buildup in plumbing and appliances, reduce the efficacy of soaps and detergents, and affect the taste of the water. A tried and true solution is the use of a water softener. A water softener, like the ones from DROP, could be a worthwhile investment.
These devices work by replacing the calcium and magnesium ions that cause hardness with sodium ions, resulting in softer water. With innovative features, easy installation, and efficient operation, DROP smart water softeners provide a solution to hard water issues, extending the lifespan of appliances, improving water taste, enhancing soap effectiveness, reducing scale build-up, and increasing the overall water efficiency in your home.