Pennsylvania water quality by county
67 counties with public water systems. Pick a county to see every system that serves it.
| County | Active systems | People served | Share with violations, 3 yr | Serious violators | Health flags |
|---|---|---|---|---|---|
| Adams County | 166 | 82,294 | 0 | 3 | |
| Allegheny County | 70 | 2,017,752 | 2 | 4 | |
| Armstrong County | 43 | 47,456 | 1 | 0 | |
| Beaver County | 94 | 179,536 | 1 | 5 | |
| Bedford County | 103 | 27,807 | 0 | 0 | |
| Berks County | 490 | 383,012 | 4 | 5 | |
| Blair County | 53 | 101,979 | 0 | 2 | |
| Bradford County | 89 | 37,911 | 2 | 0 | |
| Bucks County | 304 | 595,902 | 0 | 4 | |
| Butler County | 179 | 159,610 | 1 | 2 | |
| Cambria County | 69 | 141,472 | 2 | 2 | |
| Cameron County | 14 | 4,333 | 0 | 2 | |
| Carbon County | 161 | 69,117 | 5 | 17 | |
| Centre County | 78 | 180,570 | 2 | 0 | |
| Chester County | 269 | 301,808 | 0 | 2 | |
| Clarion County | 46 | 27,957 | 1 | 2 | |
| Clearfield County | 37 | 56,566 | 2 | 1 | |
| Clinton County | 31 | 30,967 | 1 | 0 | |
| Columbia County | 95 | 65,127 | 0 | 12 | |
| Crawford County | 178 | 55,117 | 4 | 6 | |
| Cumberland County | 102 | 248,645 | 3 | 4 | |
| Dauphin County | 144 | 294,067 | 0 | 2 | |
| Delaware County | 23 | 151,505 | 0 | 2 | |
| Elk County | 26 | 33,918 | 0 | 0 | |
| Erie County | 145 | 305,434 | 1 | 5 | |
| Fayette County | 41 | 255,694 | 1 | 2 | |
| Forest County | 22 | 6,900 | 0 | 1 | |
| Franklin County | 122 | 136,444 | 1 | 1 | |
| Fulton County | 34 | 8,730 | 1 | 1 | |
| Greene County | 9 | 46,525 | 0 | 0 | |
| Huntingdon County | 91 | 40,685 | 1 | 1 | |
| Indiana County | 54 | 54,205 | 1 | 1 | |
| Jefferson County | 42 | 30,554 | 0 | 1 | |
| Juniata County | 38 | 13,989 | 1 | 0 | |
| Lackawanna County | 119 | 175,467 | 3 | 9 | |
| Lancaster County | 427 | 409,262 | 2 | 0 | |
| Lawrence County | 64 | 75,839 | 0 | 0 | |
| Lebanon County | 111 | 101,730 | 0 | 1 | |
| Lehigh County | 203 | 294,956 | 0 | 0 | |
| Luzerne County | 247 | 324,521 | 19 | 25 | |
| Lycoming County | 131 | 88,981 | 11 | 30 | |
| McKean County | 57 | 39,910 | 2 | 2 | |
| Mercer County | 144 | 98,276 | 2 | 7 | |
| Mifflin County | 28 | 32,820 | 0 | 0 | |
| Monroe County | 444 | 188,975 | 13 | 30 | |
| Montgomery County | 167 | 1,273,934 | 0 | 1 | |
| Montour County | 21 | 15,213 | 0 | 0 | |
| Northampton County | 204 | 334,319 | 0 | 5 | |
| Northumberland County | 67 | 94,479 | 4 | 3 | |
| Perry County | 99 | 26,521 | 1 | 3 | |
| Philadelphia County | 6 | 1,601,175 | 0 | 0 | |
| Pike County | 228 | 86,407 | 8 | 11 | |
| Potter County | 45 | 12,233 | 3 | 2 | |
| Schuylkill County | 186 | 134,001 | 6 | 6 | |
| Snyder County | 48 | 23,460 | 1 | 2 | |
| Somerset County | 108 | 68,269 | 0 | 1 | |
| Sullivan County | 31 | 3,203 | 1 | 0 | |
| Susquehanna County | 116 | 29,977 | 9 | 10 | |
| Tioga County | 84 | 33,215 | 2 | 3 | |
| Union County | 38 | 8,813 | 0 | 1 | |
| Venango County | 69 | 42,470 | 1 | 2 | |
| Warren County | 64 | 31,433 | 3 | 2 | |
| Washington County | 29 | 45,621 | 2 | 1 | |
| Wayne County | 220 | 54,439 | 7 | 17 | |
| Westmoreland County | 82 | 262,778 | 3 | 3 | |
| Wyoming County | 99 | 30,658 | 6 | 8 | |
| York County | 209 | 390,174 | 1 | 3 |
under 30% 30 to 59% 60% and over
About this data
Share with violations counts any violation in the past three years, including monitoring and reporting lapses. Counts cover active systems; systems serving more than one county are counted in each.
Source: the U.S. EPA's Enforcement and Compliance History Online system (ECHO), which publishes the federal Safe Drinking Water Information System. EPA's terms and values are shown as published. The Pennsylvania records are from EPA's data refresh of Oct 7, 2026; EPA refreshes this data quarterly, and states report to EPA with a lag of three to six months, so the newest violations may not appear yet. Retrieved from ECHO on Oct 11, 2026.