Community Water System · PWS CT0570011
Aquarion-Greenwich
Operator location Shelton, Connecticut - larger served population (> 3,309) at 53,297 people served; 114 SDWIS violations on record from surface water sources.
- 53,297
- People served (this PWS)
- 114
- EPA violations (this PWS)
- 5
- Health-based (this PWS)
- 4 PFAS
- UCMR5 (this PWS)
Aquarion-Greenwich standing, high SDWIS violation third
53,297 people served (SDWIS) - larger served population (> 3,309). Corpus terciles use 29,740 systems serving 500+ (the sitemap cohort). Health-based share 4% is middle-third health share (≤ 23%). UCMR5: middle-third PFAS panel (≤ 4 compounds). Population rank #1,008 of 29,740 among systems serving 500+.
The verdict
Aquarion-Greenwich sits in the upper third of the sitemap cohort by violation count (114), so the tables below sample a dense compliance trail rather than a near-clean ledger. Population served is large (53,297; larger served population (> 3,309)), so household exposure scale sits behind the violation mix. Health-based share is 4% (middle-third health share (≤ 23%)). UCMR5 detected 4 PFAS compounds (middle-third PFAS panel (≤ 4 compounds)).
- #1,008 of 29,740
- Population · /systems
- #10 of 184
- Population · CT
- 114
- Total EPA violations on record
- 4%
- 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
- Private
- Connections
- 17,060
- County
- Fairfield
- School/Daycare
- No
- MCL Violations
- 1
- Monitoring Violations
- 97
- Treatment Tech Violations
- 4
Violation History
Contaminant violations recorded by EPA.
| Contaminant | Category | Count | Latest |
|---|---|---|---|
| Chlorite | MR | 8 | 2024 |
| Nitrite | MR | 4 | 1993 |
| Consumer Confidence Rule | Other | 4 | 2018 |
| 1,2,4-Trichlorobenzene | MR | 4 | 2018 |
| cis-1,2-Dichloroethylene | MR | 4 | 2018 |
| o-Dichlorobenzene | MR | 4 | 2018 |
| p-Dichlorobenzene | MR | 4 | 2018 |
| Vinyl chloride | MR | 4 | 2018 |
| 1,1-Dichloroethylene | MR | 4 | 2018 |
| 1,2-Dichloroethane | MR | 4 | 2018 |
| Carbon tetrachloride | MR | 4 | 2018 |
| 1,2-Dichloropropane | MR | 4 | 2018 |
| Trichloroethylene | MR | 4 | 2018 |
| CHLOROBENZENE | MR | 4 | 2018 |
| Toluene | MR | 4 | 2018 |
| CARBON, TOTAL | MR | 4 | 2018 |
| Benzene | MR | 4 | 2018 |
| Interim Enhanced Surface Water Treatment Rule | TT | 4 | 2009 |
| 1,1,2-Trichloroethane | MR | 4 | 2018 |
| Tetrachloroethylene | MR | 4 | 2018 |
| trans-1,2-Dichloroethylene | MR | 4 | 2018 |
| 1,1,1-Trichloroethane | MR | 4 | 2018 |
| Styrene | MR | 4 | 2018 |
| DICHLOROMETHANE | MR | 4 | 2018 |
| Ethylbenzene | MR | 4 | 2018 |
| Fluoride | MCL | 1 | 1979 |
| Lead and Copper Rule | MR | 1 | 2019 |
Violation Count vs. the National Corpus
Aquarion-Greenwich has 114 recorded EPA violations, 76% of the 29,740 public water systems serving 500+ people nationwide carry fewer, and 24% carry more. 4% of this system's own violations are health-based (5 of 114), and it ranks #1,008 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)
114 Higher than most more violations than 76% 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. 21 of 348 samples detected PFAS.
| Contaminant | Date | Result | MRL | Status |
|---|---|---|---|---|
| ADONA | 8/6/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFDoA | 8/6/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFHxA | 8/6/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFPeA | 8/6/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFUnA | 8/6/2025 | <2.00 ppt | 2.00 ppt | Not Detected |
| PFOA | 8/6/2025 | 4.00 ppt | 4.00 ppt | Detected |
| 9Cl-PF3ONS | 8/6/2025 | <2.00 ppt | 2.00 ppt | Not Detected |
| HFPO-DA | 8/6/2025 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFBA | 8/6/2025 | <5.00 ppt | 5.00 ppt | Not Detected |
| 6:2 FTS | 8/6/2025 | <5.00 ppt | 5.00 ppt | Not Detected |
| 4:2 FTS | 8/6/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| 8:2 FTS | 8/6/2025 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFMPA | 8/6/2025 | <4.00 ppt | 4.00 ppt | Not Detected |
| 11Cl-PF3OUdS | 8/6/2025 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFHpS | 8/6/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFMBA | 8/6/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFEESA | 8/6/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFDA | 8/6/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFPeS | 8/6/2025 | <4.00 ppt | 4.00 ppt | Not Detected |
| PFBS | 8/6/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFHpA | 8/6/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFHxS | 8/6/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFNA | 8/6/2025 | <4.00 ppt | 4.00 ppt | Not Detected |
| PFOS | 8/6/2025 | <4.00 ppt | 4.00 ppt | Not Detected |
| NFDHA | 8/6/2025 | <20.00 ppt | 20.00 ppt | Not Detected |
| 11Cl-PF3OUdS | 8/6/2025 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFHxS | 8/6/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFHpS | 8/6/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| ADONA | 8/6/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFNA | 8/6/2025 | <4.00 ppt | 4.00 ppt | Not Detected |
| PFOS | 8/6/2025 | <4.00 ppt | 4.00 ppt | Not Detected |
| PFOA | 8/6/2025 | 4.70 ppt | 4.00 ppt | Detected |
| PFDA | 8/6/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFDoA | 8/6/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFHxA | 8/6/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFUnA | 8/6/2025 | <2.00 ppt | 2.00 ppt | Not Detected |
| PFBS | 8/6/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFHpA | 8/6/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| NFDHA | 8/6/2025 | <20.00 ppt | 20.00 ppt | Not Detected |
| 9Cl-PF3ONS | 8/6/2025 | <2.00 ppt | 2.00 ppt | Not Detected |
| PFEESA | 8/6/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFMBA | 8/6/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFPeA | 8/6/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFMPA | 8/6/2025 | <4.00 ppt | 4.00 ppt | Not Detected |
| 8:2 FTS | 8/6/2025 | <5.00 ppt | 5.00 ppt | Not Detected |
| 6:2 FTS | 8/6/2025 | <5.00 ppt | 5.00 ppt | Not Detected |
| PFBA | 8/6/2025 | <5.00 ppt | 5.00 ppt | Not Detected |
| HFPO-DA | 8/6/2025 | <5.00 ppt | 5.00 ppt | Not Detected |
| 4:2 FTS | 8/6/2025 | <3.00 ppt | 3.00 ppt | Not Detected |
| PFPeS | 8/6/2025 | <4.00 ppt | 4.00 ppt | Not Detected |
Population served record for Aquarion-Greenwich
EPA SDWIS lists 53,297 people served and 17,060 connections for this PWS, confirm the service-area footprint on the federal report before comparing to municipal census totals.
Sources: EPA SDWIS
Nationwide peers
114 violations · 53,297 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 Aquarion-Greenwich
Use this system's EPA-reported record as a starting filter, not a final verdict.
- See how every tracked system in Connecticut compares on the same EPA violation measures. Connecticut 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.