Public water system · CT0570011
ActiveAquarion-Greenwich
At a glance
Aquarion-Greenwich (PWSID CT0570011) is an active community water system in Fairfield County, Connecticut. It reports serving 53,297 people through 17,060 service connections. Its primary water source is surface water, and EPA lists it as privately owned. Of the 12 most recent violations in EPA's records, none is health-based, and the most recent began in June 2024.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
53,297
Service connections
17,060
Primary source
SW
Surface water
System type
CWS
Community water system
System record
How does Aquarion-Greenwich compare with other water systems in Fairfield County?
By EPA's size categories, Aquarion-Greenwich is a large system (10,001 to 100,000 people). Fairfield County has 337 active public water systems, and Aquarion-Greenwich is the 4th-largest of them by population served. Its population served is about 23 times the county average of 2,311 people per system, and accounts for 6.8% of the 778,730 people reported by systems filed under the county. Across Connecticut, the 2,363 active systems average 1,247 people each. Nationally, the average active community water system reports serving 6,703 people, so Aquarion-Greenwich is about 8 times that figure.
What does “community water system” mean?
A community water system serves at least 15 connections used by year-round residents, or regularly serves at least 25 year-round residents. Homes, apartments and mobile-home parks are served by these. Connecticut has 481 active community water systems, 20% of the state's 2,363 active systems. Surface water means the system draws its water from rivers, lakes, streams or reservoirs. 38 Connecticut systems (1.6%) list surface water as their primary source.
Who owns and regulates Aquarion-Greenwich?
EPA lists Aquarion-Greenwich as privately owned. The CT state drinking water program is its primacy agency, the regulator with primary enforcement responsibility for the system under the Safe Drinking Water Act. 286 of the 337 active systems in Fairfield County (85%) are also privately owned.
Does Aquarion-Greenwich have drinking water violations?
Of the 12 most recent violations in EPA's records, none is health-based, and the most recent began in June 2024. The violations listed here began between January 2018 and June 2024. By type: 11 monitoring and reporting and 1 public notice, recordkeeping or other. The contaminant or rule involved most often is Carbon, total (2 of them). EPA lists 12 as resolved. Resolved means at least one resolving action is on record: the system returned to compliance, the rule no longer applies, or no further action was needed.
| Began | Violation | Contaminant or rule | Health-based | Status |
|---|---|---|---|---|
| 2024-06-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Chloritecode 1009 | No | Resolved |
| 2019-12-30 | Monitoring and reportingLead Consumer Notice · code 66 | Lead and Copper Rulecode 5000 | No | Resolved |
| 2018-11-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Carbon, totalcode 2920 | No | Resolved |
| 2018-11-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Carbon, totalcode 2920 | No | Resolved |
| 2018-07-01 | Public notice, recordkeeping or otherConsumer Confidence Report Complete Failure to Report · code 71 | Consumer Confidence Rulecode 7000 | No | Resolved |
| 2018-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Chlorobenzenecode 2989 | No | Resolved |
| 2018-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | o-Dichlorobenzenecode 2968 | No | Resolved |
| 2018-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | 1,2,4-Trichlorobenzenecode 2378 | No | Resolved |
| 2018-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | 1,1,2-Trichloroethanecode 2985 | No | Resolved |
| 2018-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Ethylbenzenecode 2992 | No | Resolved |
| 2018-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Tetrachloroethylenecode 2987 | No | Resolved |
| 2018-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Dichloromethanecode 2964 | No | Resolved |
The 12 most recent violations in EPA's records, newest first.Labels and codes come from EPA's SDWIS reference tables. A monitoring or reporting violation means a required test or report was missed or late; it does not by itself mean a contaminant was found. "Health-based" marks violations of a legal limit or required treatment.
Aquarion-Greenwich: frequently asked questions
Who runs Aquarion-Greenwich?
Aquarion-Greenwich (PWSID CT0570011) is a community water system privately owned. It is regulated by the CT state drinking water program.
How many people does Aquarion-Greenwich serve?
Aquarion-Greenwich reports serving 53,297 people through 17,060 service connections in Fairfield County, Connecticut.
Where does Aquarion-Greenwich get its water?
EPA SDWIS lists this system's primary water source as surface water. Surface water means the system draws its water from rivers, lakes, streams or reservoirs.
Does Aquarion-Greenwich have any drinking water violations?
Of the 12 most recent violations in EPA's records, none is health-based, and the most recent began in June 2024. A monitoring or reporting violation means a required test or report was missed or late; it does not by itself mean a contaminant was found.
Is Aquarion-Greenwich's water safe to drink?
AquaCensus shows EPA compliance records, not current water test results, so it cannot say whether the water is safe at a given moment. Of the 12 most recent violations in EPA's records, none is health-based, and the most recent began in June 2024. For current results, consult the system's annual water quality report, EPA ECHO, or the CT state drinking water program.
Where can I find Aquarion-Greenwich's water quality report?
As a community water system, Aquarion-Greenwich must deliver an annual water quality report, called a Consumer Confidence Report, to its customers by July 1 each year, covering the previous calendar year. The system can provide a copy on request.
Other water systems in Fairfield County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Aquarion-Eastern Fairfield County | Fairfield | 351,756 | Community | Surface water |
| Aquarion-Stamford | Fairfield | 119,214 | Community | Surface water |
| Danbury Water Department | Fairfield | 62,055 | Community | Surface water |
| South Norwalk Electric & Water | Fairfield | 42,000 | Community | Surface water |
| Norwalk First Taxing District | Fairfield | 40,256 | Community | Surface water |
| Aquarion-Darien | Fairfield | 18,737 | Community | Purchased surface water |
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About this data
Source: U.S. EPA Safe Drinking Water Information System (SDWIS) and SDWA violation records, via EPA ECHO, as published October 1, 2026 — AquaCensus refreshes it quarterly. See the methodology for how records are matched, cleaned and scored.
Cite as: AquaCensus, “Aquarion-Greenwich, PWSID CT0570011, Connecticut”, https://aquacensus.com/water-systems/connecticut/aquarion-greenwich-ct0570011 (data as of October 1, 2026).