Total Trihalomethanes (TTHMs) in Ohio Drinking Water

441 public water systems in Ohio have historical EPA violation records associated with total trihalomethanes (tthms) in the Q2 2026 snapshot.

1,511

Historical Records in Ohio

441

Systems With Records

About Total Trihalomethanes (TTHMs)

EPA Limit
80 ppb
Category
Disinfection Byproducts
Health Effects
Liver, kidney, nervous system problems; increased cancer risk
Common Treatment Approaches
Activated carbon filters

These counts describe historical compliance records, not present concentrations or household test results. Confirm current conditions with the utility's latest Consumer Confidence Report.