Public water system · CT0350011
ActiveAquarion-Darien
At a glance
Aquarion-Darien (PWSID CT0350011) is an active community water system in Fairfield County, Connecticut. It reports serving 18,737 people through 6,844 service connections. Its primary water source is purchased surface water, and EPA lists it as privately owned. EPA's records list 2 violations for this system; none is health-based, and the most recent began in July 2018.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
18,737
Service connections
6,844
Primary source
SWP
Purchased surface water
System type
CWS
Community water system
System record
How does Aquarion-Darien compare with other water systems in Fairfield County?
By EPA's size categories, Aquarion-Darien is a large system (10,001 to 100,000 people). Fairfield County has 337 active public water systems. Its population served is about 8.1 times the county average of 2,311 people per system, and accounts for 2.4% 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-Darien is about 180% above 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. Purchased surface water means the system buys surface water from another public water system rather than drawing its own. 52 Connecticut systems (2.2%) list purchased surface water as their primary source.
Who owns and regulates Aquarion-Darien?
EPA lists Aquarion-Darien 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-Darien have drinking water violations?
EPA's records list 2 violations for this system; none is health-based, and the most recent began in July 2018. The violations listed here began between July 2006 and July 2018. By type: 2 public notice, recordkeeping or other. The contaminant or rule involved most often is Consumer Confidence Rule (2 of them). EPA lists 2 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 |
|---|---|---|---|---|
| 2018-07-01 | Public notice, recordkeeping or otherConsumer Confidence Report Complete Failure to Report · code 71 | Consumer Confidence Rulecode 7000 | No | Resolved |
| 2006-07-01 | Public notice, recordkeeping or otherConsumer Confidence Report Complete Failure to Report · code 71 | Consumer Confidence Rulecode 7000 | No | Resolved |
All 2 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-Darien: frequently asked questions
Who runs Aquarion-Darien?
Aquarion-Darien (PWSID CT0350011) is a community water system privately owned. It is regulated by the CT state drinking water program.
How many people does Aquarion-Darien serve?
Aquarion-Darien reports serving 18,737 people through 6,844 service connections in Fairfield County, Connecticut.
Where does Aquarion-Darien get its water?
EPA SDWIS lists this system's primary water source as purchased surface water. Purchased surface water means the system buys surface water from another public water system rather than drawing its own.
Does Aquarion-Darien have any drinking water violations?
EPA's records list 2 violations for this system; none is health-based, and the most recent began in July 2018. 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-Darien'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. EPA's records list 2 violations for this system; none is health-based, and the most recent began in July 2018. 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-Darien's water quality report?
As a community water system, Aquarion-Darien 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 |
| Aquarion-Greenwich | Fairfield | 53,297 | Community | Surface water |
| South Norwalk Electric & Water | Fairfield | 42,000 | Community | Surface water |
| Norwalk First Taxing District | Fairfield | 40,256 | Community | 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-Darien, PWSID CT0350011, Connecticut”, https://aquacensus.com/water-systems/connecticut/aquarion-darien-ct0350011 (data as of October 1, 2026).