Measured, not modelled
Measured well-water hardness in Minidoka County, Idaho: the median of laboratory samples taken at real water wells, in grains per gallon and mg/L as CaCO3, with the number of wells behind the figure.
| Median hardness | 15 gpg — about 257 mg/L as CaCO3 |
| Rating | very hard (Water Quality Association scale) |
| Middle half of wells | 12–18.6 gpg |
| Wells measured | 143 |
| Laboratory samples | 143 |
Source: Water Quality Portal (USGS & US EPA). Water Quality Portal (USGS NWIS + EPA STORET), siteType Well, 13 analytes. These are laboratory results at water wells in the public record — not municipal tap water and not a model. The figure is a county median: individual wells vary, and only a test on the property itself gives its reading. The full table for the state is at well water hardness in Idaho, by county; the method is on the methodology page.
Ratings use the Water Quality Association scale, in grains per gallon (gpg); 1 gpg is 17.118 mg/L as CaCO3.
| Rating | Range |
|---|---|
| soft | 0 – 1 gpg |
| slightly hard | 1 – 3.5 gpg |
| moderately hard | 3.5 – 7 gpg |
| hard | 7 – 10.5 gpg |
| very hard | over 10.5 gpg |
Yes — the median across 143 measured wells, one reading each in Minidoka County is 15 grains per gallon (about 257 mg/L as CaCO3), which is “very hard” on the Water Quality Association scale. The middle half of those wells falls between 12 and 18.6 gpg, so individual wells vary widely around the median. This is groundwater measured at other wells in the county, not a reading from any one property.
At or above 7 grains per gallon a water softener is the standard treatment; the county median of 15 gpg is above that line. Only a test on the property itself confirms the reading and sizes any equipment properly.
143 distinct wells in Minidoka County carry a laboratory hardness result in the public record we read; a county is published only when at least 3 do. Nothing here is estimated from municipal tap water.
Selling water treatment here? The newly filed wells in Minidoka County are sold as part of the Idaho Falls – Pocatello territory — one dealer, exclusive.
Built from the same data that qualifies every lead Hard Water Feed sells, and regenerated with it — the figures on this page change only when the underlying public record does.