How hard is the water in Shawnee County, KS?
12.9 grains per gallon
A softener will pay its way here.
The median hardness measured in Shawnee County, KS is 220 mg/L as calcium carbonate, which is 12.9 gpg. That is very hard on the USGS scale. It comes from 1,248 samples at 31 sites between 1990 and 2023, drawn from every sampling site in the county, wells and surface water together.
How much it varies here
Half the sites came in between 7 and 16.4 gpg. That spread crosses a decision line, so some homes here land on a different answer. A $10 test strip on your own tap settles it. Confidence in the county figure: high (how it is measured).
What to do next
At 12.9 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. Because Shawnee County straddles a decision line, check your own tap with a $10 test strip before you spend anything.
More on sizing a softener for your household.
From 0.2 to 19.3 gpg
The softest single sample on record in Shawnee County was 3 mg/L and the hardest 330 mg/L, a 110-fold gap. The top quarter of sites read above 16.4 gpg and the bottom quarter below 7 gpg. So even here some sites draw water soft enough to need nothing at all.
Wells 17.1 gpg, rivers and lakes 12.9 gpg
1 groundwater samples from 1 wells put the median at 292 mg/L. 1,230 surface samples from 29 sites put it at 220 mg/L. In Shawnee County the wells come out 4.2 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 281 lb of salt a year (8 bags of 40 lb, about $51), 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 $151 a year.
Sizing at 12.9 gpg
| People | Grains a day | Unit | Salt a year |
|---|---|---|---|
| 1 | 774 | 24,000 | 94 lb |
| 2 | 1,548 | 24,000 | 188 lb |
| 4 | 3,096 | 24,000 | 377 lb |
| 6 | 4,644 | 40,000 | 565 lb |
Shawnee County against the rest of Kansas
Among the 105 Kansas counties with data, Shawnee County is number 71 of 105 counting from the hardest. Across the whole country it is harder than 61% of counties.
Softest in Kansas: Woodson County at 6.3 gpg. Hardest: Linn County at 114.5 gpg. Closest to Shawnee County: Morris County (12.9), Atchison County (12.9), Scott County (12.9).