How hard is the water in Iron County, MO?
12.7 grains per gallon
A softener will pay its way here.
The median hardness measured in Iron County, MO is 218 mg/L as calcium carbonate, which is 12.7 gpg. That is very hard on the USGS scale. It comes from 160 samples at 53 sites between 1995 and 2026, drawn from every sampling site in the county, wells and surface water together.
How much it varies here
Half the sites came in between 8.5 and 20.2 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 12.7 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 Iron 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 2.1 to 287.4 gpg
The softest single sample on record in Iron County was 36.1 mg/L and the hardest 4,920 mg/L, a 136-fold gap. The top quarter of sites read above 20.2 gpg and the bottom quarter below 8.5 gpg. So even here some sites draw water soft enough to need nothing at all.
Wells 135.2 gpg, rivers and lakes 10.7 gpg
8 groundwater samples from 4 wells put the median at 2315 mg/L. 152 surface samples from 49 sites put it at 184 mg/L. In Iron County the wells come out 124.5 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 278 lb of salt a year (7 bags of 40 lb, about $50), 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 $150 a year.
Sizing at 12.7 gpg
| People | Grains a day | Unit | Salt a year |
|---|---|---|---|
| 1 | 762 | 24,000 | 93 lb |
| 2 | 1,524 | 24,000 | 185 lb |
| 4 | 3,048 | 24,000 | 371 lb |
| 6 | 4,572 | 40,000 | 556 lb |
Iron County against the rest of Missouri
Among the 110 Missouri counties with data, Iron County is number 37 of 110 counting from the hardest. Across the whole country it is harder than 61% of counties.
Softest in Missouri: Livingston County at 4.1 gpg. Hardest: Reynolds County at 96.7 gpg. Closest to Iron County: Greene County (12.7), Daviess County (12.7), Miller County (12.8).