Public water system · CT1370051
ActiveCtwc - Shoreline Region-Masons Island
At a glance
Ctwc - Shoreline Region-Masons Island (PWSID CT1370051) is an active community water system in New London County, Connecticut. It reports serving 445 people through 194 service connections. Its primary water source is purchased surface water, and EPA lists it as privately owned. EPA's records list 10 violations for this system; 4 are health-based, and the most recent began in December 2021.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
445
Service connections
194
Primary source
SWP
Purchased surface water
System type
CWS
Community water system
System record
How does Ctwc - Shoreline Region-Masons Island compare with other water systems in New London County?
By EPA's size categories, Ctwc - Shoreline Region-Masons Island is a very small system (500 people or fewer). New London County has 394 active public water systems. Its population served is about 16% below the county average of 532 people per system, and accounts for 0.2% of the 209,444 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 Ctwc - Shoreline Region-Masons Island is well below 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 Ctwc - Shoreline Region-Masons Island?
EPA lists Ctwc - Shoreline Region-Masons Island 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. 320 of the 394 active systems in New London County (81%) are also privately owned.
Does Ctwc - Shoreline Region-Masons Island have drinking water violations?
EPA's records list 10 violations for this system; 4 are health-based, and the most recent began in December 2021. The violations listed here began between October 2004 and December 2021. By type: 6 monitoring and reporting and 4 contaminant level above the legal limit. The contaminant or rule involved most often is Haloacetic acids (HAA5) (5 of them). EPA lists 10 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 |
|---|---|---|---|---|
| 2021-12-30 | Monitoring and reportingLead Consumer Notice · code 66 | Lead and Copper Rulecode 5000 | No | Resolved |
| 2017-10-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Haloacetic acids (HAA5)code 2456 | No | Resolved |
| 2017-10-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Total trihalomethanes (TTHM)code 2950 | No | Resolved |
| 2014-12-01 | Monitoring and reportingMonitoring of Treatment (SWTR-Filter) · code 36 | Surface Water Treatment Rulecode 0200 | No | Resolved |
| 2014-12-01 | Monitoring and reportingMonitoring, Routine Minor (TCR) · code 24 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 2014-10-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Chlorinecode 0999 | No | Resolved |
| 2006-01-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Haloacetic acids (HAA5)code 2456 | Yes | Resolved |
| 2005-10-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Haloacetic acids (HAA5)code 2456 | Yes | Resolved |
| 2005-01-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Haloacetic acids (HAA5)code 2456 | Yes | Resolved |
| 2004-10-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Haloacetic acids (HAA5)code 2456 | Yes | Resolved |
All 10 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.
Ctwc - Shoreline Region-Masons Island: frequently asked questions
Who runs Ctwc - Shoreline Region-Masons Island?
Ctwc - Shoreline Region-Masons Island (PWSID CT1370051) is a community water system privately owned. It is regulated by the CT state drinking water program.
How many people does Ctwc - Shoreline Region-Masons Island serve?
Ctwc - Shoreline Region-Masons Island reports serving 445 people through 194 service connections in New London County, Connecticut.
Where does Ctwc - Shoreline Region-Masons Island 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 Ctwc - Shoreline Region-Masons Island have any drinking water violations?
EPA's records list 10 violations for this system; 4 are health-based, and the most recent began in December 2021. 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 Ctwc - Shoreline Region-Masons Island'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 10 violations for this system; 4 are health-based, and the most recent began in December 2021. For current results, consult the system's annual water quality report, EPA ECHO, or the CT state drinking water program.
Where can I find Ctwc - Shoreline Region-Masons Island's water quality report?
As a community water system, Ctwc - Shoreline Region-Masons Island 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 New London County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Norwich Public Utilities | New London | 36,163 | Community | Surface water |
| Groton Utilities | New London | 30,200 | Community | Surface water |
| New London Dept. of Public Utilities | New London | 27,620 | Community | Surface water |
| Waterford Wpca | New London | 16,578 | Community | Purchased surface water |
| East Lyme Water & Sewer Commission | New London | 15,245 | Community | Purchased surface water |
| Aquarion-Mystic | New London | 10,788 | 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, “Ctwc - Shoreline Region-Masons Island, PWSID CT1370051, Connecticut”, https://aquacensus.com/water-systems/connecticut/ctwc-shoreline-region-masons-island-ct1370051 (data as of October 1, 2026).