Public water system · CT1630011
ActiveWindham Water Works
At a glance
Windham Water Works (PWSID CT1630011) is an active community water system in Windham County, Connecticut. It reports serving 21,214 people through 4,956 service connections. Its primary water source is surface water, and EPA lists it as owned by a local government. Of the 12 most recent violations in EPA's records, 6 are health-based, and the most recent began in July 2023.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
21,214
Service connections
4,956
Primary source
SW
Surface water
System type
CWS
Community water system
System record
How does Windham Water Works compare with other water systems in Windham County?
By EPA's size categories, Windham Water Works is a large system (10,001 to 100,000 people). Windham County has 254 active public water systems, and Windham Water Works is the largest of them by population served. Its population served is about 84 times the county average of 251 people per system, and accounts for 33% of the 63,868 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 Windham Water Works is about 3.2 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 Windham Water Works?
EPA lists Windham Water Works as owned by a local government. 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. 30 of the 254 active systems in Windham County (12%) are also owned by a local government.
Does Windham Water Works have drinking water violations?
Of the 12 most recent violations in EPA's records, 6 are health-based, and the most recent began in July 2023. The violations listed here began between September 1991 and July 2023. By type: 5 required treatment not met, 4 monitoring and reporting, 2 public notice, recordkeeping or other and 1 contaminant level above the legal limit. The contaminant or rule involved most often is Surface Water Treatment Rule (5 of them). EPA lists 11 as resolved and 1 as archived. 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. Archived means the violation was not marked resolved but is more than five years past the end of the noncompliance period, so it no longer counts toward current compliance status.
| Began | Violation | Contaminant or rule | Health-based | Status |
|---|---|---|---|---|
| 2023-07-01 | Public notice, recordkeeping or otherConsumer Confidence Report Complete Failure to Report · code 71 | Consumer Confidence Rulecode 7000 | No | Resolved |
| 2018-12-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Chloritecode 1009 | No | Resolved |
| 2018-10-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Carbon, totalcode 2920 | No | Archived |
| 2006-07-01 | Public notice, recordkeeping or otherConsumer Confidence Report Complete Failure to Report · code 71 | Consumer Confidence Rulecode 7000 | No | Resolved |
| 1995-03-01 | Required treatment not metTreatment Technique (SWTR and GWR) · code 41 | Surface Water Treatment Rulecode 0200 | Yes | Resolved |
| 1995-02-01 | Required treatment not metTreatment Technique (SWTR and GWR) · code 41 | Surface Water Treatment Rulecode 0200 | Yes | Resolved |
| 1995-01-01 | Required treatment not metTreatment Technique (SWTR and GWR) · code 41 | Surface Water Treatment Rulecode 0200 | Yes | Resolved |
| 1994-12-01 | Required treatment not metTreatment Technique (SWTR and GWR) · code 41 | Surface Water Treatment Rulecode 0200 | Yes | Resolved |
| 1994-11-01 | Required treatment not metTreatment Technique (SWTR and GWR) · code 41 | Surface Water Treatment Rulecode 0200 | Yes | Resolved |
| 1991-09-01 | Monitoring and reportingMonitoring, Routine Minor (TCR) · code 24 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 1991-09-01 | Monitoring and reportingMonitoring, Repeat Minor (TCR) · code 26 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 1991-09-01 | 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.
Windham Water Works: frequently asked questions
Who runs Windham Water Works?
Windham Water Works (PWSID CT1630011) is a community water system owned by a local government. It is regulated by the CT state drinking water program.
How many people does Windham Water Works serve?
Windham Water Works reports serving 21,214 people through 4,956 service connections in Windham County, Connecticut.
Where does Windham Water Works 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 Windham Water Works have any drinking water violations?
Of the 12 most recent violations in EPA's records, 6 are health-based, and the most recent began in July 2023. 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 Windham Water Works' 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, 6 are health-based, and the most recent began in July 2023. For current results, consult the system's annual water quality report, EPA ECHO, or the CT state drinking water program.
Where can I find Windham Water Works' water quality report?
As a community water system, Windham Water Works 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 Windham County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Putnam Water Pollution Control Authority | Windham | 7,300 | Community | Surface water |
| Ctwc - Crystal System | Windham | 6,378 | Community | Groundwater |
| Ctwc - Gallup System | Windham | 2,538 | Community | Groundwater |
| Ctwc - Plainfield System | Windham | 1,713 | Community | Groundwater |
| Killingly High School & Agricultural Ctr | Windham | 1,400 | Non-transient non-community | Groundwater |
| Woodstock Academy | Windham | 1,125 | Non-transient non-community | Groundwater |
Related pages
Working with water-system records? Pro adds alerts, change history and CSV export ($49/mo); Enterprise adds full national files, the API and an MCP server for AI tools.
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, “Windham Water Works, PWSID CT1630011, Connecticut”, https://aquacensus.com/water-systems/connecticut/windham-water-works-ct1630011 (data as of October 1, 2026).