Public water system · DC0000005
ActiveNaval Observatory
At a glance
Naval Observatory (PWSID DC0000005) is an active non-transient non-community water system in District of Columbia County, District of Columbia. It reports serving 250 people through 29 service connections. Its primary water source is purchased surface water, and EPA lists it as owned by the federal government. Of the 12 most recent violations in EPA's records, one is health-based, and the most recent began in February 2025.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
250
Service connections
29
Primary source
SWP
Purchased surface water
System type
NTNCWS
Non-transient non-community water system
System record
How does Naval Observatory compare with other water systems in District of Columbia County?
By EPA's size categories, Naval Observatory is a very small system (500 people or fewer). District of Columbia County has 5 active public water systems, and Naval Observatory is the 4th-largest of them by population served. Its population served is well below the county average of 133,737 people per system, and accounts for less than 0.1% of the 668,685 people reported by systems filed under the county. Across District of Columbia, the 12 active systems average 58,113 people each. Nationally, the average active non-transient non-community water system reports serving 430 people, so Naval Observatory is about 42% below that figure.
What does “non-transient non-community water system” mean?
A non-transient non-community water system regularly serves at least 25 of the same people for more than six months a year, but not where they live. Schools, factories, office buildings and hospitals with their own supply are typical examples. District of Columbia has 7 active non-transient non-community water systems, 58% of the state's 12 active systems. Purchased surface water means the system buys surface water from another public water system rather than drawing its own. 5 District of Columbia systems (42%) list purchased surface water as their primary source.
Who owns and regulates Naval Observatory?
EPA lists Naval Observatory as owned by the federal government. The DC state drinking water program is its primacy agency, the regulator with primary enforcement responsibility for the system under the Safe Drinking Water Act. 4 of the 5 active systems in District of Columbia County (80%) are also owned by the federal government.
Does Naval Observatory have drinking water violations?
Of the 12 most recent violations in EPA's records, one is health-based, and the most recent began in February 2025. The violations listed here began between September 2008 and February 2025. By type: 7 monitoring and reporting, 3 public notice, recordkeeping or other, 1 reporting and 1 required treatment not met. The contaminant or rule involved most often is Total coliform bacteria (TCR) (4 of them). EPA lists 12 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 |
|---|---|---|---|---|
| 2025-02-11 | ReportingReport Sample Result/Fail Monitor (RTCR) · code 4B | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2016-12-31 | Monitoring and reportingLead Consumer Notice · code 66 | Lead and Copper Rulecode 5000 | No | Resolved |
| 2016-11-01 | Required treatment not metFailure To Address Deficiency · code 45 | Long Term 2 Enhanced Surface Water Treatment Rulecode 0800 | Yes | Resolved |
| 2016-05-26 | Public notice, recordkeeping or otherPublic Notification Violation for NPDWR Violation · code 75 | Public Noticecode 7500 | No | Resolved |
| 2016-05-26 | Public notice, recordkeeping or otherPublic Notification Violation for NPDWR Violation · code 75 | Public Noticecode 7500 | No | Resolved |
| 2016-04-01 | Public notice, recordkeeping or otherSample Siting Plan Errors (RTCR) · code 5A | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2015-04-01 | Monitoring and reportingMonitoring, Routine Minor (TCR) · code 24 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 2015-04-01 | Monitoring and reportingMonitoring of Treatment (SWTR-Filter) · code 36 | Long Term 2 Enhanced Surface Water Treatment Rulecode 0800 | No | Resolved |
| 2010-01-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Chloraminecode 1006 | No | Resolved |
| 2009-01-01 | Monitoring and reportingMonitoring, Routine Minor (TCR) · code 24 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 2008-09-01 | Monitoring and reportingMonitoring, Repeat Minor (TCR) · code 26 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 2008-09-01 | Monitoring and reportingMonitoring, Routine Minor (TCR) · code 24 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
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.
Naval Observatory: frequently asked questions
Who runs Naval Observatory?
Naval Observatory (PWSID DC0000005) is a non-transient non-community water system owned by the federal government. It is regulated by the DC state drinking water program.
How many people does Naval Observatory serve?
Naval Observatory reports serving 250 people through 29 service connections in District of Columbia County, District of Columbia.
Where does Naval Observatory 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 Naval Observatory 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 February 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 Naval Observatory'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 February 2025. For current results, consult EPA ECHO, or the DC state drinking water program.
Where can I find Naval Observatory's water quality report?
The annual Consumer Confidence Report requirement applies to community water systems. Naval Observatory is a non-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 District of Columbia County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| D.C. Water and Sewer Authority | District of Columbia | 632,323 | Community | Purchased surface water |
| Joint Base Anacostia - Bolling | District of Columbia | 19,312 | Community | Purchased surface water |
| Naval Station Washington - Wny | District of Columbia | 16,800 | Community | Purchased surface water |
Related pages
Working with water-system records? Pro adds alerts, change history and CSV export ($49/mo); Enterprise adds full national files, the API and an MCP server for AI tools.
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, “Naval Observatory, PWSID DC0000005, District of Columbia”, https://aquacensus.com/water-systems/district-of-columbia/naval-observatory-dc0000005 (data as of October 1, 2026).