Public water system · CT0341164
Active18 Mill Plain Road
At a glance
18 Mill Plain Road (PWSID CT0341164) is an active transient non-community water system in Fairfield County, Connecticut. It reports serving 25 people through 1 service connection. Its primary water source is groundwater, and EPA lists it as privately owned. Of the 12 most recent violations in EPA's records, 5 are health-based, and the most recent began in September 2025.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
25
Service connections
1
Primary source
GW
Groundwater
System type
TNCWS
Transient non-community water system
System record
How does 18 Mill Plain Road compare with other water systems in Fairfield County?
By EPA's size categories, 18 Mill Plain Road is a very small system (500 people or fewer). Fairfield County has 337 active public water systems. Its population served is well below the county average of 2,311 people per system, and accounts for less than 0.1% 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 transient non-community water system reports serving 144 people, so 18 Mill Plain Road is well below that figure.
What does “transient non-community water system” mean?
A transient non-community water system serves places where people do not stay long, such as gas stations and campgrounds, and regularly serves at least 25 people a day for at least 60 days a year. Connecticut has 1,399 active transient non-community water systems, 59% of the state's 2,363 active systems. Groundwater means the system draws its water from wells or springs fed by underground aquifers. 2,263 Connecticut systems (96%) list groundwater as their primary source.
Who owns and regulates 18 Mill Plain Road?
EPA lists 18 Mill Plain Road 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 18 Mill Plain Road have drinking water violations?
Of the 12 most recent violations in EPA's records, 5 are health-based, and the most recent began in September 2025. The violations listed here began between July 2010 and September 2025. By type: 4 public notice, recordkeeping or other, 3 monitoring, 3 required treatment not met and 2 contaminant level above the legal limit. The contaminant or rule involved most often is Revised Total Coliform Rule (6 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 |
|---|---|---|---|---|
| 2025-09-01 | MonitoringMonitoring, Routine (RTCR) · code 3A | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2020-12-09 | Public notice, recordkeeping or otherPublic Notification Violation for NPDWR Violation · code 75 | Public Noticecode 7500 | No | Resolved |
| 2019-09-01 | MonitoringMonitoring, Routine (RTCR) · code 3A | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2018-12-02 | Required treatment not metTreatment Technique, Level 1 Assessment (RTCR) · code 2A | Revised Total Coliform Rulecode 8000 | Yes | Resolved |
| 2018-06-06 | Public notice, recordkeeping or otherPublic Notification Violation for NPDWR Violation · code 75 | Public Noticecode 7500 | No | Resolved |
| 2017-07-23 | Public notice, recordkeeping or otherPublic Notification Violation for NPDWR Violation · code 75 | Public Noticecode 7500 | No | Resolved |
| 2017-02-05 | Required treatment not metTreatment Technique, Level 2 Assessment (RTCR) · code 2B | Revised Total Coliform Rulecode 8000 | Yes | Resolved |
| 2017-01-01 | MonitoringMonitoring, Routine (RTCR) · code 3A | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2016-12-02 | Required treatment not metTreatment Technique, Level 1 Assessment (RTCR) · code 2A | Revised Total Coliform Rulecode 8000 | Yes | Resolved |
| 2010-09-11 | Public notice, recordkeeping or otherPublic Notification Violation for NPDWR Violation · code 75 | Public Noticecode 7500 | No | Resolved |
| 2010-08-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 2010-07-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | 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.
18 Mill Plain Road: frequently asked questions
Who runs 18 Mill Plain Road?
18 Mill Plain Road (PWSID CT0341164) is a transient non-community water system privately owned. It is regulated by the CT state drinking water program.
How many people does 18 Mill Plain Road serve?
18 Mill Plain Road reports serving 25 people through 1 service connection in Fairfield County, Connecticut.
Where does 18 Mill Plain Road get its water?
EPA SDWIS lists this system's primary water source as groundwater. Groundwater means the system draws its water from wells or springs fed by underground aquifers.
Does 18 Mill Plain Road have any drinking water violations?
Of the 12 most recent violations in EPA's records, 5 are health-based, and the most recent began in September 2025. 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 18 Mill Plain Road'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, 5 are health-based, and the most recent began in September 2025. For current results, consult EPA ECHO, or the CT state drinking water program.
Where can I find 18 Mill Plain Road's water quality report?
The annual Consumer Confidence Report requirement applies to community water systems. 18 Mill Plain Road is a transient non-community water system, so it is not required to publish one; like every public water system, it must notify the people it serves about violations under EPA's public notification rules.
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, “18 Mill Plain Road, PWSID CT0341164, Connecticut”, https://aquacensus.com/water-systems/connecticut/18-mill-plain-road-ct0341164 (data as of October 1, 2026).