HardnessCheck

How hard is the water in Marquette County, WI?

13.1 grains per gallon

The median hardness measured in Marquette County, WI is 225 mg/L as calcium carbonate, which is 13.1 gpg. That is very hard on the USGS scale. It comes from 33 samples at 11 sites between 1994 and 2026, drawn from groundwater wells, which is what most taps and private wells in the county draw on.

How much it varies here

Half the sites came in between 11.4 and 16.1 gpg. The whole middle of that range gives the same answer, so a test of your own tap is unlikely to change it. Confidence in the county figure: high (how it is measured).

What to do next

At 13.1 gpg a softener pays its way here. Before you buy, check the quoted unit's grain capacity against the sizing table below, and ask whether it regenerates on demand, which uses less salt than a timer. Call your utility for its own report if you are on city water.

More on sizing a softener for your household.

From 10.5 to 29.4 gpg

The softest single sample on record in Marquette County was 179 mg/L and the hardest 503 mg/L, a 3-fold gap. The top quarter of sites read above 16.1 gpg and the bottom quarter below 11.4 gpg.

Wells 13.1 gpg, rivers and lakes 9.2 gpg

33 groundwater samples from 11 wells put the median at 225 mg/L. 34 surface samples from 14 sites put it at 157 mg/L. In Marquette County the wells come out 3.9 gpg harder. Groundwater sits in contact with rock for years and picks up calcium and magnesium as it goes, so wells usually read harder. A utility here that draws from the river can deliver noticeably different water from a private well next door.

What a softener would cost to run

For a household of 3, a 24,000-grain unit covers a week between regenerations. Expect about 287 lb of salt a year (8 bags of 40 lb, about $52), and roughly 2,346 gallons of regeneration water. Installed, most units run $1,000 to $4,500; spread over 15 years with salt, that is about $152 a year.

Sizing at 13.1 gpg

PeopleGrains a dayUnitSalt a year
178624,00096 lb
21,57224,000191 lb
43,14424,000383 lb
64,71640,000574 lb

Marquette County against the rest of Wisconsin

Among the 72 Wisconsin counties with data, Marquette County is number 35 of 72 counting from the hardest. Across the whole country it is harder than 63% of counties.

Softest in Wisconsin: Vilas County at 1.4 gpg. Hardest: Calumet County at 28.4 gpg. Closest to Marquette County: Langlade County (13.3), Columbia County (12.9), Waushara County (12.6).