Well water hardness in Pennsylvania
Across 48 counties of Pennsylvania, the median well sampled by the USGS has 6.4 gpg of hardness. Counties range from 2.4 gpg (York County) to 16.9 gpg (Cumberland 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 | ||
|---|---|---|---|---|
| Cumberland County | 16.9 | 289 | 48 | very hard |
| Lancaster County | 15.8 | 270 | 287 | very hard |
| Mifflin County | 14.8 | 254 | 37 | very hard |
| Washington County | 14.7 | 251 | 81 | very hard |
| Centre County | 14.2 | 244 | 70 | very hard |
| Philadelphia County | 13.7 | 235 | 56 | very hard |
| Blair County | 12.2 | 209 | 54 | very hard |
| Montgomery County | 12 | 205 | 70 | very hard |
| Bedford County | 11.3 | 194 | 62 | very hard |
| Erie County | 10.5 | 180 | 38 | very hard |
| Berks County | 10.1 | 173 | 66 | hard |
| Adams County | 9.9 | 170 | 39 | hard |
| Bucks County | 9.1 | 157 | 152 | hard |
| Franklin County | 8.2 | 140 | 23 | hard |
| Huntingdon County | 8.2 | 140 | 48 | hard |
| Jefferson County | 8 | 137 | 44 | hard |
| Union County | 7.9 | 136 | 11 | hard |
| Bradford County | 7.7 | 131 | 134 | hard |
| Clinton County | 7.6 | 130 | 73 | hard |
| Lebanon County | 7.6 | 130 | 93 | hard |
| Cambria County | 7 | 120 | 13 | hard |
| Tioga County | 6.8 | 116 | 27 | moderately hard |
| Clearfield County | 6.7 | 115 | 28 | moderately hard |
| Delaware County | 6.5 | 111 | 25 | moderately hard |
| Greene County | 6.4 | 110 | 49 | moderately hard |
| Indiana County | 6.4 | 110 | 277 | moderately hard |
| Wyoming County | 6.3 | 109 | 36 | moderately hard |
| Somerset County | 6.3 | 107 | 25 | moderately hard |
| Warren County | 5.8 | 100 | 95 | moderately hard |
| Dauphin County | 5.6 | 96 | 59 | moderately hard |
| Susquehanna County | 5.4 | 93 | 108 | moderately hard |
| Fayette County | 5.4 | 92 | 12 | moderately hard |
| Montour County | 5.3 | 92 | 22 | moderately hard |
| Juniata County | 4.9 | 84 | 12 | moderately hard |
| Snyder County | 4.8 | 82 | 31 | moderately hard |
| Columbia County | 4.7 | 81 | 76 | moderately hard |
| Wayne County | 4.4 | 76 | 143 | moderately hard |
| Sullivan County | 4.3 | 74 | 25 | moderately hard |
| Chester County | 4.3 | 73 | 573 | moderately hard |
| Luzerne County | 4.2 | 72 | 41 | moderately hard |
| Pike County | 4 | 69 | 142 | moderately hard |
| Lycoming County | 3.8 | 66 | 80 | moderately hard |
| Perry County | 3.7 | 64 | 36 | moderately hard |
| Fulton County | 3.7 | 64 | 12 | moderately hard |
| Schuylkill County | 3.6 | 62 | 51 | moderately hard |
| Northumberland County | 3.3 | 56 | 59 | soft |
| Potter County | 3 | 51 | 48 | soft |
| York County | 2.4 | 40 | 109 | soft |
Counties with fewer than 10 sampled wells, or a median outside 5–500 mg/L, are not shown until the figure is reviewed.
Pennsylvania: tap water hardness by city → · Well water hardness by state and county →