Well water hardness in Missouri
Across 19 counties of Missouri, the median well sampled by the USGS has 14.7 gpg of hardness. Counties range from 1.6 gpg (Pemiscot County) to 26.9 gpg (Jackson County).
Millions of American households drink water from their own well. No utility tests that water and no water quality report covers it. These pages summarise the hardness the U.S. Geological Survey measured in wells county by county, so you know what to expect before you test your own well.
Counties, hardest first
| gpg | mg/L | wells | ||
|---|---|---|---|---|
| Jackson County | 26.9 | 461 | 56 | very hard |
| Boone County | 24 | 411 | 49 | very hard |
| Franklin County | 23.3 | 399 | 22 | very hard |
| St. Charles County | 19.4 | 332 | 97 | very hard |
| Audrain County | 18.7 | 320 | 17 | very hard |
| Vernon County | 16.9 | 290 | 34 | very hard |
| Bates County | 15.8 | 270 | 10 | very hard |
| Cape Girardeau County | 15.5 | 265 | 12 | very hard |
| Pulaski County | 15 | 256 | 100 | very hard |
| Macon County | 14.7 | 251 | 11 | very hard |
| Oregon County | 14.6 | 249 | 18 | very hard |
| Shannon County | 12.6 | 216 | 20 | very hard |
| Barry County | 10 | 172 | 28 | hard |
| New Madrid County | 9.7 | 166 | 11 | hard |
| Newton County | 9.6 | 164 | 10 | hard |
| Barton County | 9.3 | 160 | 23 | hard |
| Scott County | 8.3 | 142 | 10 | hard |
| Dunklin County | 2 | 34 | 14 | soft |
| Pemiscot County | 1.6 | 28 | 11 | soft |
Counties with fewer than 10 sampled wells, or a median outside 5–500 mg/L, are not shown until the figure is reviewed.
Missouri: tap water hardness by city → · Well water hardness by state and county →