Boston Water and Sewer Commission (MWRA) water quality
Boston, MA · serves 675,647 people (88,895 connections) · Purchased surface water · Local government · EPA ID MA3035000
Data: U.S. EPA · How we read the data · How we check it
Buys water from Massachusetts Water Resources Authority (MWRA). Treated water bought from another system can carry that system's contaminants.
Summary
No federal limits exceeded in EPA data.
- PFAS
- Not detectedNone of 29 PFAS found above EPA's reporting limits in 4 samples (2023–2025).
- Lead
- Below action level5.8 ppb (parts per billion) at the 90th percentile: 9 in 10 homes sampled were at or below it. Action level 15 ppb, falling to 10 ppb in Nov 2027. Monitoring period ending Jun 2026. Your home's pipes can make yours higher.
- Violations
- Resolved1 health-based violation since 2016, most recently Nov 2020.
- Built before 1986, or not sure what your service line is made of? Check your service line and test your tap. Utility data can't show your pipes.
- Tested your own tap? Compare your result with these numbers. Moving? Compare this system with another.
- Read Boston Water and Sewer Commission (MWRA)'s 2026 water quality report (PDF) (Consumer Confidence Report, from the utility). It lists every regulated contaminant tested, including ones not on this page. Questions: (617) 989-7000.
PFAS (“forever chemicals”)
EPA UCMR 5: 1 entry point tested Jan 2024 to Oct 2024. "Average" is the highest entry-point average (non-detects counted as zero), the way EPA compares UCMR 5 results to the limits. ppt = parts per trillion. These results do not determine compliance.
| Contaminant | Highest average |
|---|---|
| PFOA Not detected Limit 4 ppt | – |
| PFOS Not detected Limit 4 ppt | – |
| PFHxS Not detected Limit 10 ppt | – |
| PFNA Not detected Limit 10 ppt | – |
| HFPO-DA (GenX) Not detected Limit 10 ppt | – |
| Hazard Index (a combined score for PFHxS, PFNA, GenX and PFBS, where above 1 is over the limit) Not detected Limit 1 | – |
| PFBS Not detected Guideline 2,000 ppt | – |
| PFBA Not detected Guideline 6,000 ppt | – |
| PFHxA Not detected Guideline 3,000 ppt | – |
29 PFAS tested, 0 detected at least once. "Not detected" means below EPA's reporting limit (about 2 to 20 ppt depending on the chemical), not proven zero. PFAS not listed were not detected. The limits for PFHxS, PFNA, GenX and the Hazard Index were proposed for rescission in May 2026. That proposal is not final. Systems have until 2029 to meet the limits.
Lithium
Not detected in 4 samples (reporting limit 9 ppb). About lithium.
Lead and copper
Latest 90th percentile: 5.8 ppb lead (Jan 2026 – Jun 2026). Below action level
Highest since 2016: 99.5 ppb (Jun 2022).
| Monitoring period | Lead (90th pct.) |
|---|---|
| Jan 2026 – Jun 2026 | 5.8 ppb |
| Jan 2025 – Dec 2025 | 22.5 ppb |
| Jul 2024 – Dec 2024 | 7.96 ppb |
Earlier results (9)
| Jan 2024 – Jun 2024 | 11.7 ppb |
| Jan 2023 – Dec 2023 | 21.3 ppb |
| Jul 2022 – Dec 2022 | 12.6 ppb |
| Jan 2022 – Jun 2022 | 99.5 ppb |
| Jul 2021 – Dec 2021 | 17.4 ppb |
| Jan 2021 – Jun 2021 | 6.88 ppb |
| Jan 2020 – Dec 2020 | 25.2 ppb |
| Jan 2019 – Dec 2019 | 11.9 ppb |
| Jan 2018 – Dec 2018 | 12.7 ppb |
Lead comes from pipes and fixtures, not the source water, so it varies home to home. The 90th percentile means 9 in 10 sampled homes were at or below it. More on lead.
Violations
| When | What happened |
|---|---|
| Nov 2020 | The system did not replace lead service lines as required. EPA record: Lead and Copper Rule · Lead Service Line Replacement (LSLR) (limit TT ) Addressed |
Health-based violations mean a contaminant exceeded a limit or a required treatment step was missed. Monitoring and reporting violations mean required tests or reports were late or missing, so the water's quality during that time is unknown. The total includes every violation in EPA's records, most of them paperwork.
Earlier EPA testing (2013–2020)
Where it serves
55 ZIP codes the system reported serving
02108, 02109, 02110, 02111, 02112, 02113, 02114, 02115, 02116, 02117, 02118, 02119, 02120, 02121, 02122, 02123, 02124, 02125, 02126, 02127, 02128, 02129, 02130, 02131, 02132, 02133, 02134, 02135, 02136, 02137, 02163, 02196, 02199, 02201, 02203, 02204, 02205, 02206, 02207, 02210, 02211, 02212, 02215, 02216, 02217, 02222, 02228, 02241, 02266, 02283, 02284, 02293, 02295, 02297, 02298
Nearby utilities
- Massachusetts Water Resources Authority (MWRA) Boston · same area
- Quincy Water Dept. (MWRA) Quincy · 5 mi
- Somerville Water Dept. (MWRA) Somerville · 6 mi
- Cambridge Water Department Cambridge · 6 mi
- Revere Water Division (MWRA) Revere · 6 mi
- Brookline Water and Sewer Division Brookline · 6 mi
Questions
Is Boston Water and Sewer Commission (MWRA) water safe to drink?
Boston Water and Sewer Commission (MWRA) had 1 health-based violation since 2016, all since resolved. EPA testing found no PFAS above the federal limits. Federal data can't tell you about your own pipes: lead comes from service lines and plumbing, so test your tap if your home was built before 1986. For the official word, read the utility's annual Consumer Confidence Report.
Does Boston Water and Sewer Commission (MWRA) water have PFAS?
EPA tested Boston Water and Sewer Commission (MWRA) for 29 PFAS between Jan 2024 and Oct 2024 and none were detected above the reporting limits (about 2 to 20 ppt depending on the chemical).
What is the lead level in Boston Water and Sewer Commission (MWRA) water?
The most recent 90th-percentile lead result for Boston Water and Sewer Commission (MWRA) is 5.8 ppb, for the period ending Jun 2026. The federal action level is 15 ppb, falling to 10 ppb in November 2027. The 90th percentile means 9 in 10 homes sampled were at or below this number. Individual homes can be higher.
Check these numbers yourself
Every figure on this page comes from public EPA records. You don't have to take our word for it:
- EPA's own report for MA3035000: violations, enforcement and inspections, straight from EPA.
- EPA UCMR 5 data: the PFAS and lithium results (search the file for PWSID MA3035000).
- EPA SDWIS download: the lead results, population and violation records we use.
- Boston Water and Sewer Commission (MWRA)'s 2026 water quality report (PDF): the utility's own annual report, including contaminants EPA's national database doesn't carry (link checked Nov 14, 2026). Phone: (617) 989-7000.
- Boston Water and Sewer Commission (MWRA) website
Found something that doesn't match? Tell us and we'll check it against EPA's records. How we check our data.
Source: U.S. EPA drinking water records and PFAS testing (UCMR 5). How we read the data.