Well water hardness in New Mexico
Across 20 counties of New Mexico, the median well sampled by the USGS has 9.5 gpg of hardness. Counties range from 1.9 gpg (McKinley County) to 26.8 gpg (Otero 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 | ||
|---|---|---|---|---|
| Otero County | 26.8 | 460 | 42 | very hard |
| Chaves County | 25.4 | 435 | 24 | very hard |
| Lincoln County | 25 | 428 | 35 | very hard |
| Sierra County | 18.1 | 310 | 46 | very hard |
| Curry County | 15.7 | 270 | 44 | very hard |
| Bernalillo County | 15.3 | 263 | 434 | very hard |
| Dona Ana County | 14.8 | 253 | 301 | very hard |
| Roosevelt County | 13.8 | 236 | 30 | very hard |
| Sandoval County | 9.9 | 170 | 50 | hard |
| Socorro County | 9.9 | 170 | 93 | hard |
| Taos County | 9.1 | 155 | 45 | hard |
| Cibola County | 8.8 | 150 | 157 | hard |
| Valencia County | 8.6 | 147 | 34 | hard |
| San Juan County | 7.7 | 132 | 85 | hard |
| Santa Fe County | 6.7 | 115 | 93 | moderately hard |
| Luna County | 6.4 | 110 | 43 | moderately hard |
| Rio Arriba County | 6.4 | 110 | 11 | moderately hard |
| Catron County | 6.1 | 105 | 60 | moderately hard |
| Hidalgo County | 3.4 | 58 | 33 | soft |
| McKinley County | 1.9 | 33 | 67 | soft |
Counties with fewer than 10 sampled wells, or a median outside 5–500 mg/L, are not shown until the figure is reviewed.