Public water system · FL2160734
ActiveN.S. Mayport
At a glance
N.S. Mayport (PWSID FL2160734) is an active community water system in Duval County, Florida. It reports serving 20,500 people through 901 service connections. Its primary water source is groundwater, and EPA lists it as owned by the federal government. EPA's records list 9 violations for this system; 6 are health-based, and the most recent began in August 2025.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
20,500
Service connections
901
Primary source
GW
Groundwater
System type
CWS
Community water system
System record
How does N.S. Mayport compare with other water systems in Duval County?
By EPA's size categories, N.S. Mayport is a large system (10,001 to 100,000 people). Duval County has 92 active public water systems, and N.S. Mayport is the 5th-largest of them by population served. Its population served is about twice the county average of 10,204 people per system, and accounts for 2.2% of the 938,721 people reported by systems filed under the county. Across Florida, the 5,197 active systems average 4,345 people each. Nationally, the average active community water system reports serving 6,703 people, so N.S. Mayport is about 3.1 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. Florida has 1,640 active community water systems, 32% of the state's 5,197 active systems. Groundwater means the system draws its water from wells or springs fed by underground aquifers. 4,996 Florida systems (96%) list groundwater as their primary source.
Who owns and regulates N.S. Mayport?
EPA lists N.S. Mayport as owned by the federal government. The FL state drinking water program is its primacy agency, the regulator with primary enforcement responsibility for the system under the Safe Drinking Water Act. 5 of the 92 active systems in Duval County (5.4%) are also owned by the federal government.
Does N.S. Mayport have drinking water violations?
EPA's records list 9 violations for this system; 6 are health-based, and the most recent began in August 2025. The violations listed here began between April 1992 and August 2025. By type: 6 contaminant level above the legal limit, 2 monitoring and reporting and 1 reporting. The contaminant or rule involved most often is Total coliform bacteria (TCR) (4 of them). EPA lists 5 as resolved and 4 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 |
|---|---|---|---|---|
| 2025-08-01 | Monitoring and reportingMonitoring, Source Water (GWR) · code 34 | E. colicode 3014 | No | Resolved |
| 2021-11-01 | ReportingReporting, Assessment Forms (RTCR) · code 4A | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2017-12-01 | Monitoring and reportingMonitoring, Source Water (GWR) · code 34 | E. colicode 3014 | No | Resolved |
| 2015-10-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 2013-07-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Total trihalomethanes (TTHM)code 2950 | 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 | Archived |
| 2008-04-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Archived |
| 1994-10-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Archived |
| 1992-04-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Single Sample · code 01 | Gross alpha (excluding radon and uranium)code 4000 | Yes | Archived |
All 9 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.
N.S. Mayport: frequently asked questions
Who runs N.S. Mayport?
N.S. Mayport (PWSID FL2160734) is a community water system owned by the federal government. It is regulated by the FL state drinking water program.
How many people does N.S. Mayport serve?
N.S. Mayport reports serving 20,500 people through 901 service connections in Duval County, Florida.
Where does N.S. Mayport 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 N.S. Mayport have any drinking water violations?
EPA's records list 9 violations for this system; 6 are health-based, and the most recent began in August 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 N.S. Mayport'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 9 violations for this system; 6 are health-based, and the most recent began in August 2025. For current results, consult the system's annual water quality report, EPA ECHO, or the FL state drinking water program.
Where can I find N.S. Mayport's water quality report?
As a community water system, N.S. Mayport 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 Duval County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Jea Major Grid | Duval | 826,664 | Community | Groundwater |
| Atlantic Beach Water System | Duval | 23,503 | Community | Groundwater |
| Jacksonville Beach WTP | Duval | 23,352 | Community | Groundwater |
| N.A.S. Jacksonville | Duval | 22,000 | Community | Groundwater |
| Neptune Beach | Duval | 7,270 | Community | Groundwater |
| Jacksonville University | Duval | 3,480 | Community | 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, “N.S. Mayport, PWSID FL2160734, Florida”, https://aquacensus.com/water-systems/florida/n-s-mayport-fl2160734 (data as of October 1, 2026).