Well water hardness in Texas
Across 43 counties of Texas, the median well sampled by the USGS has 12.3 gpg of hardness. Counties range from 0.4 gpg (Rusk County) to 27.9 gpg (Knox 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 | ||
|---|---|---|---|---|
| Knox County | 27.9 | 477 | 13 | very hard |
| Bandera County | 27.4 | 469 | 16 | very hard |
| Yoakum County | 26.6 | 456 | 21 | very hard |
| Kendall County | 24.9 | 426 | 11 | very hard |
| Burnet County | 24.9 | 426 | 10 | very hard |
| Tom Green County | 23.3 | 400 | 24 | very hard |
| Tarrant County | 21.7 | 371 | 59 | very hard |
| Pecos County | 21.6 | 369 | 47 | very hard |
| Kerr County | 20.4 | 349 | 13 | very hard |
| Williamson County | 18.8 | 321 | 32 | very hard |
| Travis County | 18 | 309 | 62 | very hard |
| Hays County | 17.9 | 306 | 57 | very hard |
| Bell County | 16.9 | 289 | 11 | very hard |
| Bexar County | 16.6 | 284 | 225 | very hard |
| Comal County | 16.5 | 283 | 54 | very hard |
| Wise County | 16.4 | 281 | 13 | very hard |
| Val Verde County | 16.4 | 280 | 13 | very hard |
| Uvalde County | 15.7 | 268 | 99 | very hard |
| Fort Bend County | 14.2 | 243 | 38 | very hard |
| Medina County | 13.9 | 238 | 68 | very hard |
| Culberson County | 13.4 | 230 | 15 | very hard |
| Bastrop County | 12.3 | 210 | 17 | very hard |
| Atascosa County | 11.8 | 203 | 14 | very hard |
| Dallam County | 11 | 189 | 10 | very hard |
| Hartley County | 11 | 188 | 10 | very hard |
| El Paso County | 9.3 | 159 | 137 | hard |
| Brazoria County | 8.6 | 147 | 20 | hard |
| Harris County | 8.5 | 145 | 240 | hard |
| Montgomery County | 6.9 | 118 | 44 | moderately hard |
| Polk County | 6.2 | 107 | 15 | moderately hard |
| Liberty County | 6 | 102 | 11 | moderately hard |
| Freestone County | 5.1 | 87 | 16 | moderately hard |
| Limestone County | 4.7 | 80 | 65 | moderately hard |
| Lee County | 4.5 | 78 | 10 | moderately hard |
| Wilson County | 4.1 | 70 | 15 | moderately hard |
| Grimes County | 3.7 | 64 | 11 | moderately hard |
| Tyler County | 3.5 | 60 | 12 | moderately hard |
| Burleson County | 2.9 | 50 | 16 | soft |
| Jasper County | 2.8 | 48 | 10 | soft |
| Jeff Davis County | 1.8 | 31 | 13 | soft |
| Brazos County | 1.7 | 30 | 12 | soft |
| Webb County | 0.8 | 14 | 37 | soft |
| Rusk County | 0.4 | 7 | 16 | soft |
Counties with fewer than 10 sampled wells, or a median outside 5–500 mg/L, are not shown until the figure is reviewed.
Texas: tap water hardness by city → · Well water hardness by state and county →