Community Water System · PWS MA2177000
Medway Water Department
Operator location Medway, Massachusetts - larger served population (> 3,309) at 13,115 people served; 370 SDWIS violations on record from groundwater sources.
- 13,115
- People served (this PWS)
- 370
- EPA violations (this PWS)
- 22
- Health-based (this PWS)
- 4 PFAS
- UCMR5 (this PWS)
Medway Water Department standing, high SDWIS violation third
13,115 people served (SDWIS) - larger served population (> 3,309). Corpus terciles use 29,740 systems serving 500+ (the sitemap cohort). Health-based share 6% is middle-third health share (≤ 23%). UCMR5: middle-third PFAS panel (≤ 4 compounds). Population rank #3,831 of 29,740 among systems serving 500+.
The verdict
Medway Water Department sits in the upper third of the sitemap cohort by violation count (370), so the tables below sample a dense compliance trail rather than a near-clean ledger. Population served is large (13,115; larger served population (> 3,309)), so household exposure scale sits behind the violation mix. Health-based share is 6% (middle-third health share (≤ 23%)). UCMR5 detected 4 PFAS compounds (middle-third PFAS panel (≤ 4 compounds)).
- #3,831 of 29,740
- Population · /systems
- #154 of 418
- Population · MA
- 370
- Total EPA violations on record
- 6%
- Health-based (MCL / treatment failure)
Population ordinals match the sitemap cohort (systems serving 500+, population_served DESC). See methodology · corpus placement.
4 PFAS "forever chemicals" detected in testing under EPA's UCMR5 monitoring program.
System Details
- System Type
- Community
- Owner Type
- Local
- Connections
- 3,852
- County
- Norfolk
- School/Daycare
- No
- MCL Violations
- 20
- Monitoring Violations
- 330
- Treatment Tech Violations
- 2
Violation History
Contaminant violations recorded by EPA.
| Contaminant | Category | Count | Latest |
|---|---|---|---|
| Coliform (TCR) | MCL | 20 | 2014 |
| Endrin | MR | 8 | 2007 |
| Heptachlor epoxide | MR | 8 | 2007 |
| Pentachlorophenol | MR | 8 | 2007 |
| Toxaphene | MR | 8 | 2007 |
| 2,4,5-TP | MR | 8 | 2007 |
| BHC-GAMMA | MR | 8 | 2007 |
| Total Polychlorinated Biphenyls (PCB) | MR | 8 | 2007 |
| 1,2-DIBROMO-3-CHLOROPROPANE | MR | 8 | 2007 |
| Di(2-ethylhexyl) phthalate | MR | 8 | 2007 |
| Dinoseb | MR | 8 | 2007 |
| Diquat | MR | 8 | 2007 |
| Endothall | MR | 8 | 2007 |
| Glyphosate | MR | 8 | 2007 |
| HEXACHLOROBENZENE | MR | 8 | 2007 |
| Hexachlorocyclopentadiene | MR | 8 | 2007 |
| Carbofuran | MR | 8 | 2007 |
| Chlordane | MR | 8 | 2007 |
| Methoxychlor | MR | 8 | 2007 |
| Dalapon | MR | 8 | 2007 |
| Di(2-ethylhexyl) adipate | MR | 8 | 2007 |
| Picloram | MR | 8 | 2007 |
| Atrazine | MR | 8 | 2007 |
| LASSO | MR | 8 | 2007 |
| 2,3,7,8-TCDD | MR | 8 | 2007 |
| Heptachlor | MR | 8 | 2007 |
| 2,4-D | MR | 8 | 2007 |
| Benzo(a)pyrene | MR | 8 | 2007 |
| ETHYLENE DIBROMIDE | MR | 8 | 2007 |
| OXAMYL | MR | 8 | 2007 |
Violation Count vs. the National Corpus
Medway Water Department has 370 recorded EPA violations, 93% of the 29,740 public water systems serving 500+ people nationwide carry fewer, and 7% carry more. 6% of this system's own violations are health-based (22 of 370), and it ranks #3,831 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)
370 Higher than most more violations than 93% 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. 8 of 116 samples detected PFAS.
| Contaminant | Date | Result | MRL | Status |
|---|---|---|---|---|
| 4:2 FTS | 4/8/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFEESA | 4/8/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| 8:2 FTS | 4/8/2025 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFMPA | 4/8/2025 | <4.00 ppt | 4.00 ppt | Not Detected |
| PFPeA | 4/8/2025 | 3.80 ppt | 3.00 ppt | Detected |
| PFMBA | 4/8/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| NFDHA | 4/8/2025 | <20.00 ppt | 20.00 ppt | Not Detected |
| PFPeS | 4/8/2025 | <4.00 ppt | 4.00 ppt | Not Detected |
| NEtFOSAA | 4/8/2025 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFTA | 4/8/2025 | <8.00 ppt | 8.00 ppt | Not Detected |
| PFTrDA | 4/8/2025 | <7.00 ppt | 7.00 ppt | Not Detected |
| 6:2 FTS | 4/8/2025 | <5.00 ppt | 5.00 ppt | Not Detected |
| 11Cl-PF3OUdS | 4/8/2025 | <5.00 ppt | 5.00 ppt | Not Detected |
| NMeFOSAA | 4/8/2025 | <6.00 ppt | 6.00 ppt | Not Detected |
| PFHpS | 4/8/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFHxS | 4/8/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| ADONA | 4/8/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFBA | 4/8/2025 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFHpA | 4/8/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFBS | 4/8/2025 | 3.00 ppt | 3.00 ppt | Detected |
| PFNA | 4/8/2025 | <4.00 ppt | 4.00 ppt | Not Detected |
| PFOS | 4/8/2025 | <4.00 ppt | 4.00 ppt | Not Detected |
| PFOA | 4/8/2025 | 7.20 ppt | 4.00 ppt | Detected |
| PFDA | 4/8/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFDoA | 4/8/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFHxA | 4/8/2025 | 3.10 ppt | 3.00 ppt | Detected |
| PFUnA | 4/8/2025 | <2.00 ppt | 2.00 ppt | Not Detected |
| 9Cl-PF3ONS | 4/8/2025 | <2.00 ppt | 2.00 ppt | Not Detected |
| HFPO-DA | 4/8/2025 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFHxS | 4/8/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| ADONA | 4/8/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| 9Cl-PF3ONS | 4/8/2025 | <2.00 ppt | 2.00 ppt | Not Detected |
| 11Cl-PF3OUdS | 4/8/2025 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFUnA | 4/8/2025 | <2.00 ppt | 2.00 ppt | Not Detected |
| PFHxA | 4/8/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFDoA | 4/8/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFDA | 4/8/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFOA | 4/8/2025 | 4.70 ppt | 4.00 ppt | Detected |
| PFNA | 4/8/2025 | <4.00 ppt | 4.00 ppt | Not Detected |
| HFPO-DA | 4/8/2025 | <5.00 ppt | 5.00 ppt | Not Detected |
| NFDHA | 4/8/2025 | <20.00 ppt | 20.00 ppt | Not Detected |
| PFOS | 4/8/2025 | <4.00 ppt | 4.00 ppt | Not Detected |
| PFBA | 4/8/2025 | <5.00 ppt | 5.00 ppt | Not Detected |
| 6:2 FTS | 4/8/2025 | <5.00 ppt | 5.00 ppt | Not Detected |
| 4:2 FTS | 4/8/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| 8:2 FTS | 4/8/2025 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFMPA | 4/8/2025 | <4.00 ppt | 4.00 ppt | Not Detected |
| PFPeA | 4/8/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFHpA | 4/8/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFEESA | 4/8/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
Population served record for Medway Water Department
EPA SDWIS lists 13,115 people served and 3,852 connections for this PWS, confirm the service-area footprint on the federal report before comparing to municipal census totals.
Sources: EPA SDWIS · MassDEP, Drinking Water Program
Nationwide peers
370 violations · 13,115 served: nearest cross-state SDWIS matches.
Cross-state systems with comparable violation load
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 Medway Water Department
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.