Public water system · NY5121217
ActiveShelter Island Slice
At a glance
Shelter Island Slice (PWSID NY5121217) is an active transient non-community water system in Suffolk County, New York. It reports serving 60 people through 1 service connection. Its primary water source is groundwater, and EPA lists it as privately owned. EPA's records list 6 violations for this system; 1 is health-based, and the most recent began in June 2024.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
60
Service connections
1
Primary source
GW
Groundwater
System type
TNCWS
Transient non-community water system
System record
How does Shelter Island Slice compare with other water systems in Suffolk County?
By EPA's size categories, Shelter Island Slice is a very small system (500 people or fewer). Suffolk County has 151 active public water systems. Its population served is well below the county average of 9,192 people per system, and accounts for less than 0.1% of the 1,387,972 people reported by systems filed under the county. Across New York, the 8,167 active systems average 2,374 people each. Nationally, the average active transient non-community water system reports serving 144 people, so Shelter Island Slice is about 58% 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. New York has 5,182 active transient non-community water systems, 63% of the state's 8,167 active systems. Groundwater means the system draws its water from wells or springs fed by underground aquifers. 7,096 New York systems (87%) list groundwater as their primary source.
Who owns and regulates Shelter Island Slice?
EPA lists Shelter Island Slice as privately owned. The NY state drinking water program is its primacy agency, the regulator with primary enforcement responsibility for the system under the Safe Drinking Water Act. 105 of the 151 active systems in Suffolk County (70%) are also privately owned.
Does Shelter Island Slice have drinking water violations?
EPA's records list 6 violations for this system; 1 is health-based, and the most recent began in June 2024. The violations listed here began between October 2014 and June 2024. By type: 2 monitoring, 2 monitoring and reporting, 1 contaminant level above the legal limit and 1 reporting. The contaminant or rule involved most often is Revised Total Coliform Rule (4 of them). EPA lists 6 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 | Contaminant level above the legal limitMaximum Contaminant Level Violation, E. coli (RTCR) · code 1A | Revised Total Coliform Rulecode 8000 | Yes | Resolved |
| 2018-08-06 | ReportingReporting, Assessment Forms (RTCR) · code 4A | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2017-04-01 | MonitoringMonitoring, Routine (RTCR) · code 3A | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2017-03-01 | MonitoringMonitoring, Routine (RTCR) · code 3A | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2016-10-01 | Monitoring and reportingMonitoring, Regular · code 03 | Nitratecode 1040 | No | Resolved |
| 2014-10-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
All 6 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.
Shelter Island Slice: frequently asked questions
Who runs Shelter Island Slice?
Shelter Island Slice (PWSID NY5121217) is a transient non-community water system privately owned. It is regulated by the NY state drinking water program.
How many people does Shelter Island Slice serve?
Shelter Island Slice reports serving 60 people through 1 service connection in Suffolk County, New York.
Where does Shelter Island Slice 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 Shelter Island Slice have any drinking water violations?
EPA's records list 6 violations for this system; 1 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 Shelter Island Slice'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 6 violations for this system; 1 is health-based, and the most recent began in June 2024. For current results, consult EPA ECHO, or the NY state drinking water program.
Where can I find Shelter Island Slice's water quality report?
The annual Consumer Confidence Report requirement applies to community water systems. Shelter Island Slice 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 Suffolk County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Suffolk County Water Authority | Suffolk | 1,100,000 | Community | Groundwater |
| South Huntington Water District | Suffolk | 81,760 | Community | Groundwater |
| Greenlawn Water District | Suffolk | 42,000 | Community | Groundwater |
| Riverhead Water District | Suffolk | 35,000 | Community | Groundwater |
| Dix Hills Water District | Suffolk | 34,522 | Community | Groundwater |
| Smithtown Water District | Suffolk | 19,635 | Community | Purchased groundwater |
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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, “Shelter Island Slice, PWSID NY5121217, New York”, https://aquacensus.com/water-systems/new-york/shelter-island-slice-ny5121217 (data as of October 1, 2026).