EPA SDWIS DataRhode Island

Total Trihalomethanes (TTHM) in Rhode Island Drinking Water

Rhode Island has 1,147 public water systems. 586 have recorded total trihalomethanes (tthm) violations.

Total Systems

1,147

With Violations

586

EPA MCL

0.08

Population Served

1.1M

Total Trihalomethanes (TTHM) in Rhode Island: Key Facts

Total Water Systems

1,147

Systems with Violations

586

Lead Violations

30

Copper Violations

78

EPA Standard

0.08 mg/L

Water Systems with Violations in Rhode Island

SystemPopulationViolations
BETHEL VILLAGE WATER ASSN180600
AEGEAN PIZZA155589
CHIMERA INC133562
NEW ENGLAND FARMS75546
PRUDENCE ISLAND WATER DISTRICT2K506
ROCKLAND OAKS AN026469
LAWRENCE SUNSET COVE ASSOCIATION36449
COOPER HILL OFFICE COMPLEX75418

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 Rhode Island water?

Rhode Island has 1,147 public water systems. 586 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 Rhode Island 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