EPA data as of Oct 2026 · page updated 2026-10-30

MWRA

MWRA (EPA ID MA6000000) in Chelsea, MA supplies surface water (rivers, lakes) to about 2,580,000 people: no health-based violations since 2016, latest lead result 5.9 ppb, PFAS not tested.

System facts

People served2,580,000
Connections186
Sourcesurface water (rivers, lakes)
WholesalerYes

Health-based violations

No health-based violations reported since 2016.

Lead

Jan 20255.9 ppb
Jan 20246.9 ppb
Jan 202310.8 ppb
Jan 20227.3 ppb
Jan 20218.6 ppb
Jan 20206.5 ppb
Jan 20198 ppb
Jan 20189.7 ppb

90th-percentile lead per sampling round (90% of the homes sampled were at or below this level). Black line: EPA’s 15 ppb action level; under the Lead and Copper Rule Improvements the action level becomes 10 ppb from 2027.

PFAS

This system was not part of EPA’s 2023–2025 nationwide PFAS testing (UCMR 5).

What this is — and isn’t. These are records your water utility and state reported to the EPA, and the EPA’s radon map for your county. They describe the system and the area, not the water from your own tap or the air in your home. For that, read your utility’s annual Consumer Confidence Report and test: lead and radon tests are inexpensive.

Questions

Has MWRA had drinking water violations?

No health-based violations reported since 2016.

What is the lead level in MWRA water?

The latest 90th-percentile lead result (Jan 2025) was 5.9 ppb. EPA’s action level is 15 ppb (10 ppb from 2027).

Does MWRA have PFAS in its water?

This system was not part of EPA’s 2023–2025 nationwide PFAS testing (UCMR 5 covers systems serving over 3,300 people and a sample of smaller ones).