Public water system · MD1101107
ActiveJefferson Market
At a glance
Jefferson Market (PWSID MD1101107) is an active transient non-community water system in Frederick County, Maryland. It reports serving 606 people through 1 service connection. Its primary water source is groundwater, and EPA lists it as privately owned. EPA's records list 6 violations for this system; all are health-based, and the most recent began in December 2010.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
606
Service connections
1
Primary source
GW
Groundwater
System type
TNCWS
Transient non-community water system
System record
How does Jefferson Market compare with other water systems in Frederick County?
By EPA's size categories, Jefferson Market is a small system (501 to 3,300 people). Frederick County has 211 active public water systems. Its population served is about 40% below the county average of 1,007 people per system, and accounts for 0.3% of the 212,367 people reported by systems filed under the county. Across Maryland, the 2,992 active systems average 1,947 people each. Nationally, the average active transient non-community water system reports serving 144 people, so Jefferson Market is about 4.2 times 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. Maryland has 2,079 active transient non-community water systems, 69% 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 Jefferson Market?
EPA lists Jefferson Market as privately owned. 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. 156 of the 211 active systems in Frederick County (74%) are also privately owned.
Does Jefferson Market have drinking water violations?
EPA's records list 6 violations for this system; all are health-based, and the most recent began in December 2010. The violations listed here began between April 1991 and December 2010. By type: 6 contaminant level above the legal limit. The contaminant or rule involved most often is Total coliform bacteria (TCR) (5 of them). EPA lists 5 as resolved and 1 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 |
|---|---|---|---|---|
| 2010-12-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 2002-12-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Acute (TCR) · code 21 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 2001-03-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 1996-07-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Acute (TCR) · code 21 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 1994-01-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 1991-04-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Single Sample · code 01 | Nitratecode 1040 | Yes | Archived |
All 6 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.
Jefferson Market: frequently asked questions
Who runs Jefferson Market?
Jefferson Market (PWSID MD1101107) is a transient non-community water system privately owned. It is regulated by the MD state drinking water program.
How many people does Jefferson Market serve?
Jefferson Market reports serving 606 people through 1 service connection in Frederick County, Maryland.
Where does Jefferson Market 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 Jefferson Market have any drinking water violations?
EPA's records list 6 violations for this system; all are health-based, and the most recent began in December 2010. 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 Jefferson Market'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 6 violations for this system; all are health-based, and the most recent began in December 2010. For current results, consult EPA ECHO, or the MD state drinking water program.
Where can I find Jefferson Market's water quality report?
The annual Consumer Confidence Report requirement applies to community water systems. Jefferson Market 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 Frederick County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| New Design - Frederick County | Frederick | 74,911 | Community | Surface water |
| City of Frederick | Frederick | 54,000 | Community | Surface water |
| Town of Walkersville | Frederick | 8,440 | Community | Groundwater under influence of surface water |
| Fort Detrick | Frederick | 7,900 | Community | Surface water |
| City of Brunswick | Frederick | 7,312 | Community | Surface water |
| Town of Thurmont | Frederick | 6,200 | Community | Groundwater under influence of 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, “Jefferson Market, PWSID MD1101107, Maryland”, https://aquacensus.com/water-systems/maryland/jefferson-market-md1101107 (data as of October 1, 2026).