Public water system · NY5121859
ActiveDering Harbor Corp
At a glance
Dering Harbor Corp (PWSID NY5121859) is an active transient non-community water system in Suffolk County, New York. It reports serving 250 people through 30 service connections. Its primary water source is groundwater, and EPA lists it as privately owned. EPA's records list 3 violations for this system; all are health-based, and the most recent began in July 2020.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
250
Service connections
30
Primary source
GW
Groundwater
System type
TNCWS
Transient non-community water system
System record
How does Dering Harbor Corp compare with other water systems in Suffolk County?
By EPA's size categories, Dering Harbor Corp 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 Dering Harbor Corp is about 74% above 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 Dering Harbor Corp?
EPA lists Dering Harbor Corp 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 Dering Harbor Corp have drinking water violations?
EPA's records list 3 violations for this system; all are health-based, and the most recent began in July 2020. The violations listed here began between July 2004 and July 2020. By type: 3 contaminant level above the legal limit. The contaminant or rule involved most often is Total coliform bacteria (TCR) (2 of them). EPA lists 3 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 |
|---|---|---|---|---|
| 2020-07-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, E. coli (RTCR) · code 1A | Revised Total Coliform Rulecode 8000 | Yes | Resolved |
| 2008-07-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 2004-07-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
All 3 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.
Dering Harbor Corp: frequently asked questions
Who runs Dering Harbor Corp?
Dering Harbor Corp (PWSID NY5121859) is a transient non-community water system privately owned. It is regulated by the NY state drinking water program.
How many people does Dering Harbor Corp serve?
Dering Harbor Corp reports serving 250 people through 30 service connections in Suffolk County, New York.
Where does Dering Harbor Corp 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 Dering Harbor Corp have any drinking water violations?
EPA's records list 3 violations for this system; all are health-based, and the most recent began in July 2020. 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 Dering Harbor Corp'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 3 violations for this system; all are health-based, and the most recent began in July 2020. For current results, consult EPA ECHO, or the NY state drinking water program.
Where can I find Dering Harbor Corp's water quality report?
The annual Consumer Confidence Report requirement applies to community water systems. Dering Harbor Corp 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, “Dering Harbor Corp, PWSID NY5121859, New York”, https://aquacensus.com/water-systems/new-york/dering-harbor-corp-ny5121859 (data as of October 1, 2026).