How hard is the water in Doniphan County, KS?
14.9 grains per gallon
A softener will pay its way here.
The median hardness measured in Doniphan County, KS is 255 mg/L as calcium carbonate, which is 14.9 gpg. That is very hard on the USGS scale. It comes from 209 samples at 7 sites between 1990 and 2016, drawn from every sampling site in the county, wells and surface water together.
How much it varies here
Half the sites came in between 14.3 and 18.8 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: medium (how it is measured).
What to do next
At 14.9 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.
More on sizing a softener for your household.
From 12.9 to 23.7 gpg
The softest single sample on record in Doniphan County was 220 mg/L and the hardest 406 mg/L, a 2-fold gap. The top quarter of sites read above 18.8 gpg and the bottom quarter below 14.3 gpg.
Wells 19.2 gpg, rivers and lakes 14.9 gpg
2 groundwater samples from 2 wells put the median at 328 mg/L. 207 surface samples from 5 sites put it at 255 mg/L. In Doniphan County the wells come out 4.3 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 325 lb of salt a year (9 bags of 40 lb, about $59), 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 $159 a year.
Sizing at 14.9 gpg
| People | Grains a day | Unit | Salt a year |
|---|---|---|---|
| 1 | 894 | 24,000 | 109 lb |
| 2 | 1,788 | 24,000 | 218 lb |
| 4 | 3,576 | 32,000 | 435 lb |
| 6 | 5,364 | 40,000 | 653 lb |
Doniphan County against the rest of Kansas
Among the 105 Kansas counties with data, Doniphan County is number 57 of 105 counting from the hardest. Across the whole country it is harder than 69% of counties.
Softest in Kansas: Woodson County at 6.3 gpg. Hardest: Linn County at 114.5 gpg. Closest to Doniphan County: Trego County (15.1), Marshall County (15.2), Ford County (14.5).