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Public water system · NJ1101316

Active

Etra Lake Park

At a glance

Etra Lake Park (PWSID NJ1101316) is an active transient non-community water system in Mercer County, New Jersey. It reports serving 50 people through 2 service connections. Its primary water source is groundwater, and EPA lists it as owned by a local government. Of the 12 most recent violations in EPA's records, one is health-based, and the most recent began in October 2025.

Dataset updated . Source: EPA SDWIS/ECHO public records.

Population served

50

Service connections

2

Primary source

GW

Groundwater

System type

TNCWS

Transient non-community water system

System record

PWSIDNJ1101316
System typeTransient non-community water system
Activity statusActive
Population served50
Service connections2
Primary water sourceGroundwater
Owner typeLocal government
Primacy agencyNJ state drinking water program
City servedEast Windsor Twp.-1101
StateNew Jersey
ZIP—
CountyMercer County

How does Etra Lake Park compare with other water systems in Mercer County?

By EPA's size categories, Etra Lake Park is a very small system (500 people or fewer). Mercer County has 97 active public water systems. Its population served is well below the county average of 3,340 people per system, and accounts for less than 0.1% of the 323,956 people reported by systems filed under the county. Across New Jersey, the 3,496 active systems average 2,750 people each. Nationally, the average active transient non-community water system reports serving 144 people, so Etra Lake Park is about 65% 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 Jersey has 2,277 active transient non-community water systems, 65% of the state's 3,496 active systems. Groundwater means the system draws its water from wells or springs fed by underground aquifers. 3,313 New Jersey systems (95%) list groundwater as their primary source.

Who owns and regulates Etra Lake Park?

EPA lists Etra Lake Park as owned by a local government. The NJ state drinking water program is its primacy agency, the regulator with primary enforcement responsibility for the system under the Safe Drinking Water Act. 17 of the 97 active systems in Mercer County (18%) are also owned by a local government.

Does Etra Lake Park have drinking water violations?

Of the 12 most recent violations in EPA's records, one is health-based, and the most recent began in October 2025. The violations listed here began between January 1999 and October 2025. By type: 7 monitoring and reporting, 2 reporting, 2 monitoring and 1 contaminant level above the legal limit. The contaminant or rule involved most often is Total coliform bacteria (TCR) (7 of them). EPA lists 8 as resolved, 3 as archived and 1 as unaddressed. 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. Unaddressed means the violation is not resolved or archived and is not yet covered by formal enforcement.

BeganViolationContaminant or ruleHealth-basedStatus
2025-10-01ReportingReport Sample Result/Fail Monitor (RTCR) · code 4BRevised Total Coliform Rulecode 8000NoUnaddressed
2025-07-01MonitoringMonitoring, Routine (RTCR) · code 3ARevised Total Coliform Rulecode 8000NoArchived
2021-04-11ReportingReport Sample Result/Fail Monitor (RTCR) · code 4BRevised Total Coliform Rulecode 8000NoResolved
2021-01-01MonitoringMonitoring, Routine (RTCR) · code 3ARevised Total Coliform Rulecode 8000NoResolved
2012-07-01Monitoring and reportingMonitoring, Routine Major (TCR) · code 23Total coliform bacteria (TCR)code 3100NoResolved
2011-01-01Monitoring and reportingMonitoring, Regular · code 03Nitratecode 1040NoResolved
2010-09-01Monitoring and reportingMonitoring, Routine Major (TCR) · code 23Total coliform bacteria (TCR)code 3100NoResolved
2010-07-01Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22Total coliform bacteria (TCR)code 3100YesResolved
2002-07-01Monitoring and reportingMonitoring, Routine Major (TCR) · code 23Total coliform bacteria (TCR)code 3100NoArchived
2001-07-01Monitoring and reportingMonitoring, Routine Major (TCR) · code 23Total coliform bacteria (TCR)code 3100NoArchived
1999-07-01Monitoring and reportingMonitoring, Routine Major (TCR) · code 23Total coliform bacteria (TCR)code 3100NoResolved
1999-01-01Monitoring and reportingMonitoring, Routine Major (TCR) · code 23Total coliform bacteria (TCR)code 3100NoResolved

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.

Etra Lake Park: frequently asked questions

Who runs Etra Lake Park?

Etra Lake Park (PWSID NJ1101316) is a transient non-community water system owned by a local government. It is regulated by the NJ state drinking water program.

How many people does Etra Lake Park serve?

Etra Lake Park reports serving 50 people through 2 service connections in Mercer County, New Jersey.

Where does Etra Lake Park 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 Etra Lake Park have any drinking water violations?

Of the 12 most recent violations in EPA's records, one is health-based, and the most recent began in October 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 Etra Lake Park'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, one is health-based, and the most recent began in October 2025. For current results, consult EPA ECHO, or the NJ state drinking water program.

Where can I find Etra Lake Park's water quality report?

The annual Consumer Confidence Report requirement applies to community water systems. Etra Lake Park 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 Mercer County

Water systemCountyPopulation servedTypeSource
Trenton Water WorksMercer217,000CommunitySurface water
Aqua Nj - Hamilton SquareMercer39,128CommunityPurchased surface water
East Windsor MuaMercer25,000CommunityGroundwater
Aqua Nj - LawrenceMercer8,655CommunityGroundwater under influence of surface water
Hightstown Water DepartmentMercer5,400CommunityGroundwater
Pennington Shop-RiteMercer3,663Non-transient non-communityGroundwater

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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, “Etra Lake Park, PWSID NJ1101316, New Jersey”, https://aquacensus.com/water-systems/new-jersey/etra-lake-park-nj1101316 (data as of October 1, 2026).