TTHM (Total Trihalomethanes) violations in Pennsylvania
535 active public water systems in Pennsylvania had a TTHM (Total Trihalomethanes) violation in the past three years, 39 of them in the latest quarter of EPA's data. What TTHM (Total Trihalomethanes) is and why it matters.
Systems with a TTHM (Total Trihalomethanes) violation
Latest quarter first, then largest first| System | Serves | Status | Rules violated, 3 yr | Unresolved |
|---|---|---|---|---|
|
Dvsd Dingman Delaware Campus Pike County |
1,965 | 3 | 0 | |
|
Youngsville Mun Waterworks Warren County |
1,957 | 3 | 0 | |
|
Centre Hall Boro Water Dept Centre County |
1,900 | 4 | 0 | |
|
Grand View Hospital Bucks County |
1,880 | 1 | 0 | |
|
E Armstrong Cnty Muni Auth Armstrong County |
1,875 | 6 | 0 | |
|
Rimersburg Boro Muni Auth Clarion County |
1,873 | 2 | 0 | |
|
Patton Boro Water Dept Cambria County |
1,805 | 3 | 0 | |
|
Wysox Twp Municipal Authority Bradford County |
1,763 | 3 | 0 | |
|
North Warren Muni Authority Warren County |
1,749 | 5 | 0 | |
|
Reade Twp Muni Auth Cambria County |
1,746 | 3 | 0 | |
|
Cbsd Central Bucks East HS Bucks County |
1,725 | 3 | 0 | |
|
Braddock Boro Water Auth Allegheny County |
1,708 | 1 | 0 | |
|
Mont Alto Municipal Authority Franklin County |
1,705 | 3 | 0 | |
|
Plumstead Twp Patriots Ridge Bucks County |
1,704 | 1 | 0 | |
|
Covington Karthaus Girard a a Clearfield County |
1,700 | 2 | 0 | |
|
US Army Garrison Cumberland County |
1,700 | 4 | 0 | |
|
Saxton Muni Water Auth Bedford County |
1,675 | 7 | 1 | |
|
Linesville Municipal Authority Crawford County |
1,600 | 1 | 0 | |
|
Brady Twp Water Association Clearfield County |
1,570 | 4 | 0 | |
|
Westmoreland Hospital Westmoreland County |
1,500 | 5 | 1 | |
|
Hawthorn Redbank Redbank MA Clarion County |
1,500 | 5 | 1 | |
|
Imperial Point Water Service Erie County |
1,500 | 1 | 0 | |
|
Sykesville Borough Jefferson County |
1,500 | 5 | 1 | |
|
Worthington West Franklin Jma Armstrong County |
1,500 | 5 | 0 | |
|
Solanco High Sch Lancaster County |
1,460 | 1 | 0 | |
|
Oakdale Boro Water Dept Allegheny County |
1,459 | 2 | 0 | |
|
Manheim Auto Auction Lancaster County |
1,426 | 2 | 0 | |
|
Delta Boro Water Sys York County |
1,400 | 5 | 1 | |
|
Freedom Twp Water & Sewer Blair County |
1,400 | 3 | 0 | |
|
Grampian Boro Penn Twp MA Clearfield County |
1,400 | 1 | 0 | |
|
RB Walter & Williamson Schools Tioga County |
1,400 | 2 | 1 | |
|
South Side Sch Beaver County |
1,400 | 6 | 1 | |
|
Roulette Twp Water Authority Potter County |
1,300 | 7 | 1 | |
|
Village of Neshaminy Falls Montgomery County |
1,300 | 4 | 0 | |
|
Cargill Meat Solutions Corp Bradford County |
1,250 | 4 | 0 | |
|
Ellsworth Boro Water Dept Washington County |
1,250 | 5 | 1 | |
|
Rockwood Boro Muni Auth Somerset County |
1,250 | 3 | 0 | |
|
Indian Lake Boro Waterworks Somerset County |
1,246 | 2 | 0 | |
|
Orbisonia Rockhill JT Mun Auth Huntingdon County |
1,200 | 4 | 1 | |
|
Parkhouse Nursing & Rehab Ctr Montgomery County |
1,200 | 3 | 0 | |
|
Swift Middle Sch Lancaster County |
1,200 | 1 | 0 | |
|
Wyalusing Area School District Bradford County |
1,200 | 2 | 0 | |
|
Springboro Area Water Auth Crawford County |
1,175 | 2 | 0 | |
|
Mill Creek Area Mun Auth Huntingdon County |
1,108 | 2 | 1 | |
|
Bowmansville Travel Plaza Lancaster County |
1,100 | 3 | 0 | |
|
Cbsd Tohickon Middle School Bucks County |
1,100 | 1 | 0 | |
|
Peter J. Camiel Service Plaza Chester County |
1,100 | 6 | 1 | |
|
Pilot Travel Center Butler County |
1,100 | 1 | 0 | |
|
The Escape Pike County |
1,100 | 6 | 0 | |
|
Royalton Boro Dauphin County |
1,083 | 1 | 0 |
About this data
A system is counted once if any of its violations in the past three years involved TTHM (Total Trihalomethanes), including monitoring and reporting lapses. Rules violated and status in the table are for the whole system, not TTHM (Total Trihalomethanes) alone.
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.