How hard is the water in Oregon County, MO?
13.4 grains per gallon
A softener will pay its way here.
The median hardness measured in Oregon County, MO is 229 mg/L as calcium carbonate, which is 13.4 gpg. That is very hard on the USGS scale. It comes from 151 samples at 25 sites between 1990 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 11.5 and 15.9 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 13.4 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 7.1 to 20.3 gpg
The softest single sample on record in Oregon County was 121.1 mg/L and the hardest 347 mg/L, a 3-fold gap. The top quarter of sites read above 15.9 gpg and the bottom quarter below 11.5 gpg.
Wells 13.4 gpg, rivers and lakes 12.1 gpg
151 groundwater samples from 25 wells put the median at 229 mg/L. 336 surface samples from 17 sites put it at 207 mg/L. In Oregon County the wells come out 1.3 gpg harder. Groundwater sits in contact with rock for years and picks up calcium and magnesium as it goes, so wells usually read harder. The two sources are close, so the county figure should hold whichever one your tap is on.
What a softener would cost to run
For a household of 3, a 24,000-grain unit covers a week between regenerations. Expect about 292 lb of salt a year (8 bags of 40 lb, about $53), 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 $153 a year.
Sizing at 13.4 gpg
| People | Grains a day | Unit | Salt a year |
|---|---|---|---|
| 1 | 804 | 24,000 | 98 lb |
| 2 | 1,608 | 24,000 | 196 lb |
| 4 | 3,216 | 24,000 | 391 lb |
| 6 | 4,824 | 40,000 | 587 lb |
Oregon County against the rest of Missouri
Among the 110 Missouri counties with data, Oregon County is number 28 of 110 counting from the hardest. Across the whole country it is harder than 64% of counties.
Softest in Missouri: Livingston County at 4.1 gpg. Hardest: Reynolds County at 96.7 gpg. Closest to Oregon County: DeKalb County (13.4), Carter County (13.3), Warren County (13.3).