Community Water System · PWS CT1180021
Aquarion-Ridgefield Knolls
Operator location Shelton, Connecticut - 24% of 228 violations are health-based (upper-third health share (> 23%)); groundwater source; 958 served per SDWIS.
- 958
- People served (this PWS)
- 228
- EPA violations (this PWS)
- 55
- Health-based (this PWS)
- Untested
- UCMR5 (this PWS)
Aquarion-Ridgefield Knolls standing, high SDWIS violation third
24% of 228 recorded violations are health-based - upper-third health share (> 23%). Corpus terciles use 29,740 systems serving 500+ (the sitemap cohort). Health-based share 24% is upper-third health share (> 23%). Population rank #20,266 of 29,740 among systems serving 500+.
The verdict
Aquarion-Ridgefield Knolls sits in the upper third of the sitemap cohort by violation count (228), so the tables below sample a dense compliance trail rather than a near-clean ledger. Population served is smaller (958; smaller served population (≤ 999)), so each violation row represents a compact service footprint. Health-based share is 24% - most of this ledger is MCL or treatment-technique exceedance. No UCMR5 PFAS test appears for this system in this extract.
- #20,266 of 29,740
- Population · /systems
- #104 of 184
- Population · CT
- 228
- Total EPA violations on record
- 24%
- Health-based (MCL / treatment failure)
Population ordinals match the sitemap cohort (systems serving 500+, population_served DESC). See methodology · corpus placement.
System Details
- System Type
- Community
- Owner Type
- Private
- Connections
- 223
- County
- Fairfield
- School/Daycare
- No
- MCL Violations
- 46
- Monitoring Violations
- 157
- Treatment Tech Violations
- 9
Violation History
Contaminant violations recorded by EPA.
| Contaminant | Category | Count | Latest |
|---|---|---|---|
| Coliform (TCR) | MCL | 46 | 2003 |
| Coliform (TCR) | MR | 15 | 2006 |
| Lead and Copper Rule | MR | 10 | 2021 |
| Lead and Copper Rule | TT | 9 | 2008 |
| Consumer Confidence Rule | Other | 6 | 2018 |
| 1,1,2-Trichloroethane | MR | 4 | 1993 |
| Trichloroethylene | MR | 4 | 1993 |
| 1,2-Dichloropropane | MR | 4 | 1993 |
| 1,2-Dichloroethane | MR | 4 | 1993 |
| trans-1,2-Dichloroethylene | MR | 4 | 1993 |
| 1,1-Dichloroethylene | MR | 4 | 1993 |
| Vinyl chloride | MR | 4 | 1993 |
| p-Dichlorobenzene | MR | 4 | 1993 |
| DICHLOROMETHANE | MR | 4 | 1993 |
| ETHYLENE DIBROMIDE | MR | 4 | 1993 |
| Beryllium, Total | MR | 4 | 1991 |
| Antimony, Total | MR | 4 | 1991 |
| Selenium | MR | 4 | 1991 |
| Nickel | MR | 4 | 1991 |
| Mercury | MR | 4 | 1991 |
| Coliform (TCR) | Other | 4 | 1995 |
| CYANIDE | MR | 4 | 1991 |
| Chromium | MR | 4 | 1991 |
| Cadmium | MR | 4 | 1991 |
| Barium | MR | 4 | 1991 |
| Benzene | MR | 4 | 1993 |
| Toluene | MR | 4 | 1993 |
| o-Dichlorobenzene | MR | 4 | 1993 |
| 1,1,1-Trichloroethane | MR | 4 | 1993 |
| CHLOROBENZENE | MR | 4 | 1993 |
Violation Count vs. the National Corpus
Aquarion-Ridgefield Knolls has 228 recorded EPA violations, 87% of the 29,740 public water systems serving 500+ people nationwide carry fewer, and 13% carry more. 24% of this system's own violations are health-based (55 of 228), and it ranks #20,266 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)
228 Higher than most more violations than 87% 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
Health-based violations on Aquarion-Ridgefield Knolls
55 health-based rows in the tables above map to MCL or treatment-technique exceedances, verify each contaminant code on the federal SDWIS report for CT1180021.
Sources: EPA SDWIS
Nationwide peers
228 violations · 958 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 smaller service footprints
Nearest cross-state systems by EPA SDWIS population_served (same 500+ sitemap gate).
What to do with Aquarion-Ridgefield Knolls
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.