Community Water System · PWS MA4131000
Weir River Water System
Operator location Hingham, Massachusetts - UCMR5 detected 5 PFAS compounds (upper-third PFAS panel (> 4 compounds)) on this PWS; SDWIS lists 41 violations and 45,339 people served.
- 45,339
- People served (this PWS)
- 41
- EPA violations (this PWS)
- 2
- Health-based (this PWS)
- 5 PFAS
- UCMR5 (this PWS)
Weir River Water System standing, mid SDWIS violation third
UCMR5 detected 5 PFAS compounds - upper-third PFAS panel (> 4 compounds). Corpus terciles use 29,740 systems serving 500+ (the sitemap cohort). Health-based share 5% is middle-third health share (≤ 23%). UCMR5: upper-third PFAS panel (> 4 compounds). Population rank #1,219 of 29,740 among systems serving 500+.
The verdict
Weir River Water System lands in the middle third by violation volume (41), large enough for peer comparisons without matching the fleet's heaviest ledgers. Population served is large (45,339; larger served population (> 3,309)), so household exposure scale sits behind the violation mix. Health-based share is 5% (middle-third health share (≤ 23%)). UCMR5 detected 5 PFAS compounds (upper-third PFAS panel (> 4 compounds)).
- #1,219 of 29,740
- Population · /systems
- #39 of 418
- Population · MA
- 41
- Total EPA violations on record
- 5%
- Health-based (MCL / treatment failure)
Population ordinals match the sitemap cohort (systems serving 500+, population_served DESC). See methodology · corpus placement.
5 PFAS "forever chemicals" detected in testing under EPA's UCMR5 monitoring program.
System Details
- System Type
- Community
- Owner Type
- Local
- Connections
- 12,755
- County
- Plymouth
- School/Daycare
- No
- MCL Violations
- 1
- Monitoring Violations
- 30
- Treatment Tech Violations
- 1
Violation History
Contaminant violations recorded by EPA.
| Contaminant | Category | Count | Latest |
|---|---|---|---|
| Hexachlorocyclopentadiene | MR | 1 | 2021 |
| OXAMYL | MR | 1 | 2021 |
| Simazine | MR | 1 | 2021 |
| 2,3,7,8-TCDD | MR | 1 | 2021 |
| Atrazine | MR | 1 | 2021 |
| 2,4-D | MR | 1 | 2021 |
| Endrin | MR | 1 | 2021 |
| ETHYLENE DIBROMIDE | MR | 1 | 2021 |
| Heptachlor epoxide | MR | 1 | 2021 |
| Pentachlorophenol | MR | 1 | 2021 |
| BHC-GAMMA | MR | 1 | 2021 |
| Dalapon | MR | 1 | 2021 |
| Di(2-ethylhexyl) adipate | MR | 1 | 2021 |
| Di(2-ethylhexyl) phthalate | MR | 1 | 2021 |
| Diquat | MR | 1 | 2021 |
| Endothall | MR | 1 | 2021 |
| Surface Water Treatment Rule | TT | 1 | 1992 |
| Glyphosate | MR | 1 | 2021 |
| Heptachlor | MR | 1 | 2021 |
| Total Polychlorinated Biphenyls (PCB) | MR | 1 | 2021 |
| HEXACHLOROBENZENE | MR | 1 | 2021 |
| Picloram | MR | 1 | 2021 |
| Toxaphene | MR | 1 | 2021 |
| Dinoseb | MR | 1 | 2021 |
| Chlordane | MR | 1 | 2021 |
| 2,4,5-TP | MR | 1 | 2021 |
| 1,2-DIBROMO-3-CHLOROPROPANE | MR | 1 | 2021 |
| LASSO | MR | 1 | 2021 |
| Carbofuran | MR | 1 | 2021 |
| Coliform (TCR) | MCL | 1 | 1999 |
Violation Count vs. the National Corpus
Weir River Water System has 41 recorded EPA violations, 51% of the 29,740 public water systems serving 500+ people nationwide carry fewer, and 48% carry more. 5% of this system's own violations are health-based (2 of 41), and it ranks #1,219 of 29,740 by population served among that same cohort.
EPA violations vs. the national water-system corpus
Public water systems serving 500+ people (EPA SDWIS)
41 Around the middle fewer violations than 48% of 29,740 water systems
the national water-system corpus, bucketed by value
Each bar is a band; taller bars hold more water systems. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count and share, and where it sits relative to this entry.
Source EPA SDWIS · 2026-05-15
PFAS Testing Results (UCMR5)
Results from EPA's Fifth Unregulated Contaminant Monitoring Rule. 17 of 232 samples detected PFAS.
| Contaminant | Date | Result | MRL | Status |
|---|---|---|---|---|
| ADONA | 8/18/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| 9Cl-PF3ONS | 8/18/2025 | <2.00 ppt | 2.00 ppt | Not Detected |
| 11Cl-PF3OUdS | 8/18/2025 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFHxA | 8/18/2025 | 3.00 ppt | 3.00 ppt | Detected |
| PFDA | 8/18/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFOA | 8/18/2025 | 6.40 ppt | 4.00 ppt | Detected |
| PFBS | 8/18/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFNA | 8/18/2025 | <4.00 ppt | 4.00 ppt | Not Detected |
| PFUnA | 8/18/2025 | <2.00 ppt | 2.00 ppt | Not Detected |
| PFHxS | 8/18/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFHpA | 8/18/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFTA | 8/18/2025 | <8.00 ppt | 8.00 ppt | Not Detected |
| PFOS | 8/18/2025 | <4.00 ppt | 4.00 ppt | Not Detected |
| NMeFOSAA | 8/18/2025 | <6.00 ppt | 6.00 ppt | Not Detected |
| PFHpS | 8/18/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFDoA | 8/18/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFPeS | 8/18/2025 | <4.00 ppt | 4.00 ppt | Not Detected |
| HFPO-DA | 8/18/2025 | <5.00 ppt | 5.00 ppt | Not Detected |
| NEtFOSAA | 8/18/2025 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFTrDA | 8/18/2025 | <7.00 ppt | 7.00 ppt | Not Detected |
| NFDHA | 8/18/2025 | <20.00 ppt | 20.00 ppt | Not Detected |
| PFEESA | 8/18/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFPeA | 8/18/2025 | 3.20 ppt | 3.00 ppt | Detected |
| PFMPA | 8/18/2025 | <4.00 ppt | 4.00 ppt | Not Detected |
| PFBA | 8/18/2025 | 5.70 ppt | 5.00 ppt | Detected |
| 8:2 FTS | 8/18/2025 | <5.00 ppt | 5.00 ppt | Not Detected |
| 4:2 FTS | 8/18/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| 6:2 FTS | 8/18/2025 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFMBA | 8/18/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFMPA | 8/18/2025 | <4.00 ppt | 4.00 ppt | Not Detected |
| 8:2 FTS | 8/18/2025 | <5.00 ppt | 5.00 ppt | Not Detected |
| 4:2 FTS | 8/18/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFBA | 8/18/2025 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFMBA | 8/18/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFPeA | 8/18/2025 | 4.30 ppt | 3.00 ppt | Detected |
| ADONA | 8/18/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| 9Cl-PF3ONS | 8/18/2025 | <2.00 ppt | 2.00 ppt | Not Detected |
| PFEESA | 8/18/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFUnA | 8/18/2025 | <2.00 ppt | 2.00 ppt | Not Detected |
| 6:2 FTS | 8/18/2025 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFHxA | 8/18/2025 | 4.30 ppt | 3.00 ppt | Detected |
| PFDoA | 8/18/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFDA | 8/18/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| 11Cl-PF3OUdS | 8/18/2025 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFBS | 8/18/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| HFPO-DA | 8/18/2025 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFTrDA | 8/18/2025 | <7.00 ppt | 7.00 ppt | Not Detected |
| PFOA | 8/18/2025 | 5.60 ppt | 4.00 ppt | Detected |
| NFDHA | 8/18/2025 | <20.00 ppt | 20.00 ppt | Not Detected |
| NMeFOSAA | 8/18/2025 | <6.00 ppt | 6.00 ppt | Not Detected |
UCMR5 PFAS record for Weir River Water System
Open EPA SDWIS federal reports for PWS MA4131000 to cross-check UCMR5 detections and violation codes; state primacy agencies enforce the Safe Drinking Water Act locally.
Sources: EPA SDWIS · MassDEP, Drinking Water Program
Nationwide peers
41 violations · 45,339 served: nearest cross-state SDWIS matches.
Cross-state systems near this violation count
Nearest cross-state community systems (500+ served) by total SDWIS violations on record.
Cross-state systems with similar served population
Nearest cross-state systems by EPA SDWIS population_served (same 500+ sitemap gate).
What to do with Weir River Water System
Use this system's EPA-reported record as a starting filter, not a final verdict.
- See how every tracked system in Massachusetts compares on the same EPA violation measures. Massachusetts systems
- Check whether PFAS was detected at this system under UCMR5 testing. PFAS guide
- Find and compare another public water system by name or PWSID. Search systems
EPA SDWIS and UCMR5 figures are informational only, not a substitute for a certified lab test of your own tap water.