EPA SDWIS DataPennsylvania

Total Trihalomethanes (TTHM) in Pennsylvania Drinking Water

Pennsylvania has 22,622 public water systems. 19019 have recorded total trihalomethanes (tthm) violations.

Total Systems

22,622

With Violations

19,019

EPA MCL

0.08

Population Served

12.6M

Total Trihalomethanes (TTHM) in Pennsylvania: Key Facts

Total Water Systems

22,622

Systems with Violations

19,019

Lead Violations

1,206

Copper Violations

970

EPA Standard

0.08 mg/L

Water Systems with Violations in Pennsylvania

SystemPopulationViolations
CONGREGATION OHR MENACHEM309908
STOCKTON WATER SYSTEM857105
SALEM HEIGHTS ESTATE626572
SCOTT MOBILE HOME PARK645814
PA AMERICAN AUDUBON8K5456
AQUA PA SUN VALLEY1204752
GAHAGEN WATER ASSN494465
LYON HILLS HOA753749

Health Effects of Total Trihalomethanes (TTHM) Exposure

Cancer risk

Long-term exposure increases bladder cancer risk

Reproductive effects

Some evidence of adverse pregnancy outcomes

Liver/kidney stress

High chronic exposure may stress liver and kidneys

Long-term exposure: increased risk of cancer (bladder). Some evidence of reproductive effects.

Frequently Asked Questions

Is there total trihalomethanes (tthm) in Pennsylvania water?

Pennsylvania has 22,622 public water systems. 19019 have recorded total trihalomethanes (tthm) violations based on EPA SDWIS data. If you are on a private well, your water is not covered by these regulations and should be tested independently.

How can I check my Pennsylvania water for total trihalomethanes (tthm)?

Search for your water system using the WaterCheck system lookup, or contact your utility and request a copy of your Consumer Confidence Report (CCR). The CCR is published annually and lists all detected contaminants, their levels, and the EPA MCLs. For private wells, contact a state-certified lab for independent testing.

What is the EPA limit for total trihalomethanes (tthm)?

The EPA Maximum Contaminant Level (MCL) for total trihalomethanes (tthm) is 0.08 mg/L. Systems that exceed MCLs are required to notify customers and take corrective action.

Total Trihalomethanes (TTHM) at a Glance

Categorydisinfection byproduct
EPA MCL0.08 mg/L

Source

Byproduct of drinking water chlorination; reaction of chlorine with organic matter

How to Filter Total Trihalomethanes (TTHM)

  • +Activated carbon filters reduce TTHMs effectively
  • +Reverse osmosis also removes TTHMs
  • +Letting water sit uncovered may reduce some volatile TTHMs