Public water system · MD0040011
ActivePrince Frederick
At a glance
Prince Frederick (PWSID MD0040011) is an active community water system in Calvert County, Maryland. It reports serving 4,371 people through 1,561 service connections. Its primary water source is groundwater, and EPA lists it as owned by a local government. EPA's records list 7 violations for this system; none is health-based, and the most recent began in April 2024.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
4,371
Service connections
1,561
Primary source
GW
Groundwater
System type
CWS
Community water system
System record
How does Prince Frederick compare with other water systems in Calvert County?
By EPA's size categories, Prince Frederick is a medium system (3,301 to 10,000 people). Calvert County has 203 active public water systems, and Prince Frederick is the 3rd-largest of them by population served. Its population served is about 11 times the county average of 384 people per system, and accounts for 5.6% of the 77,996 people reported by systems filed under the county. Across Maryland, the 2,992 active systems average 1,947 people each. Nationally, the average active community water system reports serving 6,703 people, so Prince Frederick is about 35% below 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. Maryland has 422 active community water systems, 14% of the state's 2,992 active systems. Groundwater means the system draws its water from wells or springs fed by underground aquifers. 2,870 Maryland systems (96%) list groundwater as their primary source.
Who owns and regulates Prince Frederick?
EPA lists Prince Frederick as owned by a local government. The MD state drinking water program is its primacy agency, the regulator with primary enforcement responsibility for the system under the Safe Drinking Water Act. 39 of the 203 active systems in Calvert County (19%) are also owned by a local government.
Does Prince Frederick have drinking water violations?
EPA's records list 7 violations for this system; none is health-based, and the most recent began in April 2024. The violations listed here began between July 2008 and April 2024. By type: 6 monitoring and reporting and 1 public notice, recordkeeping or other. The contaminant or rule involved most often is Lead and Copper Rule (2 of them). EPA lists 7 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 |
|---|---|---|---|---|
| 2024-04-01 | Monitoring and reportingMonitoring, Regular · code 03 | Radium-228code 4030 | No | Resolved |
| 2014-10-01 | Monitoring and reportingFollow-up Or Routine LCR Tap M/R · code 52 | Lead and Copper Rulecode 5000 | No | Resolved |
| 2011-10-01 | Monitoring and reportingFollow-up Or Routine LCR Tap M/R · code 52 | Lead and Copper Rulecode 5000 | No | Resolved |
| 2010-01-15 | Monitoring and reportingMonitoring, Routine (IDSE) · code 30 | Stage 2 Disinfectants and Disinfection Byproducts Rulecode 0600 | No | Resolved |
| 2010-01-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Total trihalomethanes (TTHM)code 2950 | No | Resolved |
| 2010-01-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Haloacetic acids (HAA5)code 2456 | No | Resolved |
| 2008-07-01 | Public notice, recordkeeping or otherConsumer Confidence Report Complete Failure to Report · code 71 | Consumer Confidence Rulecode 7000 | No | Resolved |
All 7 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.
Prince Frederick: frequently asked questions
Who runs Prince Frederick?
Prince Frederick (PWSID MD0040011) is a community water system owned by a local government. It is regulated by the MD state drinking water program.
How many people does Prince Frederick serve?
Prince Frederick reports serving 4,371 people through 1,561 service connections in Calvert County, Maryland.
Where does Prince Frederick 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 Prince Frederick have any drinking water violations?
EPA's records list 7 violations for this system; none is health-based, and the most recent began in April 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 Prince Frederick'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 7 violations for this system; none is health-based, and the most recent began in April 2024. For current results, consult the system's annual water quality report, EPA ECHO, or the MD state drinking water program.
Where can I find Prince Frederick's water quality report?
As a community water system, Prince Frederick 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 Calvert County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Chesapeake Ranch Estates | Calvert | 9,500 | Community | Groundwater |
| Town of Chesapeake Beach | Calvert | 5,000 | Community | Groundwater |
| Solomons | Calvert | 3,811 | Community | Groundwater |
| Town of North Beach | Calvert | 3,000 | Community | Groundwater |
| Northern Middle & High Schools | Calvert | 2,470 | Non-transient non-community | Groundwater |
| Chesapeake Church | Calvert | 2,050 | Transient non-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, “Prince Frederick, PWSID MD0040011, Maryland”, https://aquacensus.com/water-systems/maryland/prince-frederick-md0040011 (data as of October 1, 2026).