Williamstown Water Dept
Published drinking-water records and contacts for Williamstown Water Dept. System MA1341000. Review sources and dates; not a real-time water assessment.
- System ID
- MA1341000
- State or territory
- MA
- Published population served
- 7326
- System type (source code)
- CWS
Published records and dates
- PFAS / lithium (EPA UCMR 5): 180 — 2025-03-18 – 2025-11-12
- Lead and copper monitoring summaries: 13 — 1992-07-01 – 2021-12-31
- Massachusetts EEA PFAS monitoring results: 337 — 2021-04-14 – 2024-11-18
Missing records here do not mean the provider did not test. Published records are not a real-time assessment of your tap water.
Published testing results
Selected recent records are shown below. Different sampling locations and dates are not interchangeable. These excerpts are not a complete testing history.
“<” means below the stated reporting limit, not zero. A reported measurement alone is not a safety verdict. Read an example
| Substance | Published result | Reporting limit | Sample date | Sampling location |
|---|---|---|---|---|
| 11Cl-PF3OUdS | < 0.005 µg/L | 0.005 µg/L | 2025-11-12 | GREEN RIVER WELL (03G) / 10549 |
| 4:2 FTS | < 0.003 µg/L | 0.003 µg/L | 2025-11-12 | GREEN RIVER WELL (03G) / 10549 |
| 6:2 FTS | < 0.005 µg/L | 0.005 µg/L | 2025-11-12 | GREEN RIVER WELL (03G) / 10549 |
| 8:2 FTS | < 0.005 µg/L | 0.005 µg/L | 2025-11-12 | GREEN RIVER WELL (03G) / 10549 |
| 9Cl-PF3ONS | < 0.002 µg/L | 0.002 µg/L | 2025-11-12 | GREEN RIVER WELL (03G) / 10549 |
| ADONA | < 0.003 µg/L | 0.003 µg/L | 2025-11-12 | GREEN RIVER WELL (03G) / 10549 |
| HFPO-DA | < 0.005 µg/L | 0.005 µg/L | 2025-11-12 | GREEN RIVER WELL (03G) / 10549 |
| NEtFOSAA | < 0.005 µg/L | 0.005 µg/L | 2025-11-12 | GREEN RIVER WELL (03G) / 10549 |
| NFDHA | < 0.02 µg/L | 0.02 µg/L | 2025-11-12 | GREEN RIVER WELL (03G) / 10549 |
| NMeFOSAA | < 0.006 µg/L | 0.006 µg/L | 2025-11-12 | GREEN RIVER WELL (03G) / 10549 |
| PFBA | < 0.005 µg/L | 0.005 µg/L | 2025-11-12 | GREEN RIVER WELL (03G) / 10549 |
| PFBS | < 0.003 µg/L | 0.003 µg/L | 2025-11-12 | GREEN RIVER WELL (03G) / 10549 |
| PFDA | < 0.003 µg/L | 0.003 µg/L | 2025-11-12 | GREEN RIVER WELL (03G) / 10549 |
| PFDoA | < 0.003 µg/L | 0.003 µg/L | 2025-11-12 | GREEN RIVER WELL (03G) / 10549 |
| PFEESA | < 0.003 µg/L | 0.003 µg/L | 2025-11-12 | GREEN RIVER WELL (03G) / 10549 |
| PFHpA | < 0.003 µg/L | 0.003 µg/L | 2025-11-12 | GREEN RIVER WELL (03G) / 10549 |
| PFHpS | < 0.003 µg/L | 0.003 µg/L | 2025-11-12 | GREEN RIVER WELL (03G) / 10549 |
| PFHxA | < 0.003 µg/L | 0.003 µg/L | 2025-11-12 | GREEN RIVER WELL (03G) / 10549 |
| PFHxS | < 0.003 µg/L | 0.003 µg/L | 2025-11-12 | GREEN RIVER WELL (03G) / 10549 |
| PFMBA | < 0.003 µg/L | 0.003 µg/L | 2025-11-12 | GREEN RIVER WELL (03G) / 10549 |
| PFMPA | < 0.004 µg/L | 0.004 µg/L | 2025-11-12 | GREEN RIVER WELL (03G) / 10549 |
| PFNA | < 0.004 µg/L | 0.004 µg/L | 2025-11-12 | GREEN RIVER WELL (03G) / 10549 |
| PFOA | < 0.004 µg/L | 0.004 µg/L | 2025-11-12 | GREEN RIVER WELL (03G) / 10549 |
| PFOS | < 0.004 µg/L | 0.004 µg/L | 2025-11-12 | GREEN RIVER WELL (03G) / 10549 |
| PFPeA | < 0.003 µg/L | 0.003 µg/L | 2025-11-12 | GREEN RIVER WELL (03G) / 10549 |
| PFPeS | < 0.004 µg/L | 0.004 µg/L | 2025-11-12 | GREEN RIVER WELL (03G) / 10549 |
| PFTA | < 0.008 µg/L | 0.008 µg/L | 2025-11-12 | GREEN RIVER WELL (03G) / 10549 |
| PFTrDA | < 0.007 µg/L | 0.007 µg/L | 2025-11-12 | GREEN RIVER WELL (03G) / 10549 |
| PFUnA | < 0.002 µg/L | 0.002 µg/L | 2025-11-12 | GREEN RIVER WELL (03G) / 10549 |
| lithium | < 9 µg/L | 9 µg/L | 2025-09-23 | STETSON RD WELL #2 (02G) / 10544 |
Download all EPA UCMR 5 records (CSV)
Lead and copper: 90th-percentile summaries
These describe a monitoring period across sampled locations, not the result at your home. How to read the 90th percentile
| Substance | Published 90th percentile | Monitoring period | Source quarter |
|---|---|---|---|
| Lead (PB90) | 0 mg/L | 2019-01-01 – 2021-12-31 | 2026Q3 |
| Lead (PB90) | 0 mg/L | 2016-01-01 – 2018-12-31 | 2026Q3 |
| Lead (PB90) | 0 mg/L | 2013-01-01 – 2015-12-31 | 2026Q3 |
| Lead (PB90) | 0.0011 mg/L | 2010-01-01 – 2012-12-31 | 2026Q3 |
| Lead (PB90) | 0.0016 mg/L | 2007-01-01 – 2009-12-31 | 2026Q3 |
| Lead (PB90) | 0.002 mg/L | 2003-01-01 – 2003-12-31 | 2026Q3 |
| Lead (PB90) | 0.003 mg/L | 2000-01-01 – 2000-12-31 | 2026Q3 |
| Lead (PB90) | 0.003 mg/L | 1997-01-01 – 1997-12-31 | 2026Q3 |
| Substance | Published result | Sample date | Location / source |
|---|---|---|---|
| PERFLUOROOCTANOIC ACID-PFOA | Below a limit; numeric threshold unavailable ng/L | 2024-11-18 | POINT OF ENTRY POST TREATMENT / Massachusetts EEA PFAS monitoring results |
| PERFLUORONONANOIC ACID-PFNA | Below a limit; numeric threshold unavailable ng/L | 2024-11-18 | POINT OF ENTRY POST TREATMENT / Massachusetts EEA PFAS monitoring results |
| PERFLUOROHEPTANOIC ACID-PFHPA | Below a limit; numeric threshold unavailable ng/L | 2024-11-18 | POINT OF ENTRY POST TREATMENT / Massachusetts EEA PFAS monitoring results |
| PERFLUOROHEXANESULFONIC ACID-PFHXS | Below a limit; numeric threshold unavailable ng/L | 2024-11-18 | POINT OF ENTRY POST TREATMENT / Massachusetts EEA PFAS monitoring results |
| HEXAFLUOROPROPYLENE OXIDE DIMER ACID - HFPO-DA | Below a limit; numeric threshold unavailable ng/L | 2024-11-18 | POINT OF ENTRY POST TREATMENT / Massachusetts EEA PFAS monitoring results |
| PERFLUOROBUTANESULFONIC ACID-PFBS | Below a limit; numeric threshold unavailable ng/L | 2024-11-18 | POINT OF ENTRY POST TREATMENT / Massachusetts EEA PFAS monitoring results |
| PERFLUORODODECANOIC ACID - PFDOA | Below a limit; numeric threshold unavailable ng/L | 2024-11-18 | POINT OF ENTRY POST TREATMENT / Massachusetts EEA PFAS monitoring results |
| 11-CHLOROEICOSAFLUORO-3-OXAUNDECANE-1-SULFONIC ACID-11CL-PF3OUDS | Below a limit; numeric threshold unavailable ng/L | 2024-11-18 | POINT OF ENTRY POST TREATMENT / Massachusetts EEA PFAS monitoring results |
| N-METHYL PERFLUOROOCTANESULFONAMIDOACETIC ACID - NMEFOSAA | Below a limit; numeric threshold unavailable ng/L | 2024-11-18 | POINT OF ENTRY POST TREATMENT / Massachusetts EEA PFAS monitoring results |
| PERFLUOROHEXANOIC ACID - PFHXA | Below a limit; numeric threshold unavailable ng/L | 2024-11-18 | POINT OF ENTRY POST TREATMENT / Massachusetts EEA PFAS monitoring results |
| PERFLUORODECANOIC ACID - PFDA | Below a limit; numeric threshold unavailable ng/L | 2024-11-18 | POINT OF ENTRY POST TREATMENT / Massachusetts EEA PFAS monitoring results |
| PERFLUOROUNDECANOIC ACID - PFUNA | Below a limit; numeric threshold unavailable ng/L | 2024-11-18 | POINT OF ENTRY POST TREATMENT / Massachusetts EEA PFAS monitoring results |
State sampling points can include untreated water. Publisher qualifiers and units are retained; consult the full source notes before interpreting a record.
Download state records with source notes (CSV)
Published compliance history
6 imported records. Status is as recorded in the source; historical records are not current advisories. Missing records do not establish that no violations occurred.
| Rule / record | Period | Recorded status | Health-based (EPA classification) | Source quarter |
|---|---|---|---|---|
| Lead and Copper Rule / Follow-up Or Routine LCR Tap M/R | 2015-06-01 – — | Addressed | No | 2026Q3 |
| Lead and Copper Rule / Lead Consumer Notice | 2015-06-01 – — | Addressed | No | 2026Q3 |
| Nitrate Rule / Monitoring, Regular | 1995-04-01 – 1995-06-30 | Archived | No | 2026Q3 |
| Miscellaneous Other Rules / Notification, Public | 1982-03-31 – 1982-04-30 | Archived | No | 2026Q3 |
| Miscellaneous Other Rules / Notification, Public | 1981-12-31 – 1982-01-30 | Archived | No | 2026Q3 |
| Miscellaneous Other Rules / Notification, Public | 1981-11-30 – 1981-12-29 | Archived | No | 2026Q3 |
Source dates and refresh checks
A refresh check is not a sample date. Publication periods, sample dates and checks are shown separately.
- EPA SDWIS lead/copper summaries and service areas — source period: — – —; last checked: 2026-10-17
- EPA SDWIS contacts and compliance records — source period: — – —; last checked: 2026-10-17
- EPA UCMR 5 sample results — source period: 2023-01-03 – 2026-06-17; last checked: 2026-10-17
- Massachusetts EEA PFAS monitoring results — last successful check: 2026-10-12
Administrative contact (EPA filing)
Williamstown Water Dept: 4134583383
An administrative filing contact may not be a customer-service line. Confirm current contact details with the provider.