Well water hardness in Oregon
Across 14 counties of Oregon, the median well sampled by the USGS has 6 gpg of hardness. Counties range from 1.7 gpg (Coos County) to 7.9 gpg (Washington 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 | ||
|---|---|---|---|---|
| Washington County | 7.9 | 136 | 79 | hard |
| Lane County | 7.4 | 127 | 11 | hard |
| Linn County | 7.1 | 122 | 19 | hard |
| Jackson County | 6.7 | 115 | 24 | moderately hard |
| Morrow County | 6.6 | 113 | 21 | moderately hard |
| Marion County | 6.2 | 106 | 13 | moderately hard |
| Josephine County | 6.1 | 105 | 32 | moderately hard |
| Multnomah County | 5.9 | 101 | 16 | moderately hard |
| Umatilla County | 4.7 | 81 | 65 | moderately hard |
| Harney County | 3.5 | 61 | 61 | moderately hard |
| Deschutes County | 3.2 | 54 | 71 | soft |
| Douglas County | 3.2 | 54 | 26 | soft |
| Clackamas County | 3.1 | 54 | 16 | soft |
| Coos County | 1.7 | 29 | 108 | soft |
Counties with fewer than 10 sampled wells, or a median outside 5–500 mg/L, are not shown until the figure is reviewed.
Oregon: tap water hardness by city → · Well water hardness by state and county →