Public water system · MD1121239
ActiveGunpowder Falls St Pk Jerusalem Mill
At a glance
Gunpowder Falls St Pk Jerusalem Mill (PWSID MD1121239) is an active transient non-community water system in Harford County, Maryland. It reports serving 103 people through 1 service connection. Its primary water source is groundwater, and EPA lists it as owned by a state government. EPA's records list 7 violations for this system; none is health-based, and the most recent began in January 2025.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
103
Service connections
1
Primary source
GW
Groundwater
System type
TNCWS
Transient non-community water system
System record
How does Gunpowder Falls St Pk Jerusalem Mill compare with other water systems in Harford County?
By EPA's size categories, Gunpowder Falls St Pk Jerusalem Mill is a very small system (500 people or fewer). Harford County has 226 active public water systems. Its population served is well below the county average of 956 people per system, and accounts for less than 0.1% of the 215,993 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 Gunpowder Falls St Pk Jerusalem Mill is about 28% 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. 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 Gunpowder Falls St Pk Jerusalem Mill?
EPA lists Gunpowder Falls St Pk Jerusalem Mill as owned by a state 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. 5 of the 226 active systems in Harford County (2.2%) are also owned by a state government.
Does Gunpowder Falls St Pk Jerusalem Mill have drinking water violations?
EPA's records list 7 violations for this system; none is health-based, and the most recent began in January 2025. The violations listed here began between January 2005 and January 2025. By type: 5 monitoring and 2 monitoring and reporting. The contaminant or rule involved most often is Revised Total Coliform Rule (5 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 |
|---|---|---|---|---|
| 2025-01-01 | MonitoringMonitoring, Routine (RTCR) · code 3A | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2024-01-01 | MonitoringMonitoring, Routine (RTCR) · code 3A | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2023-07-01 | MonitoringMonitoring, Routine (RTCR) · code 3A | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2023-04-01 | MonitoringMonitoring, Routine (RTCR) · code 3A | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2020-04-01 | MonitoringMonitoring, Routine (RTCR) · code 3A | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2020-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Nitratecode 1040 | No | Resolved |
| 2005-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Nitratecode 1040 | 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.
Gunpowder Falls St Pk Jerusalem Mill: frequently asked questions
Who runs Gunpowder Falls St Pk Jerusalem Mill?
Gunpowder Falls St Pk Jerusalem Mill (PWSID MD1121239) is a transient non-community water system owned by a state government. It is regulated by the MD state drinking water program.
How many people does Gunpowder Falls St Pk Jerusalem Mill serve?
Gunpowder Falls St Pk Jerusalem Mill reports serving 103 people through 1 service connection in Harford County, Maryland.
Where does Gunpowder Falls St Pk Jerusalem Mill 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 Gunpowder Falls St Pk Jerusalem Mill have any drinking water violations?
EPA's records list 7 violations for this system; none is health-based, and the most recent began in January 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 Gunpowder Falls St Pk Jerusalem Mill'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 January 2025. For current results, consult EPA ECHO, or the MD state drinking water program.
Where can I find Gunpowder Falls St Pk Jerusalem Mill's water quality report?
The annual Consumer Confidence Report requirement applies to community water systems. Gunpowder Falls St Pk Jerusalem Mill 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 Harford County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Harford County D.P.W. | Harford | 104,567 | Community | Surface water |
| City of Aberdeen | Harford | 18,006 | Community | Purchased surface water |
| Chapel Hill - Aberdeen Proving Grounds | Harford | 15,000 | Community | Groundwater |
| City of Havre De Grace | Harford | 14,000 | Community | Surface water |
| Maryland American Water Company | Harford | 13,200 | Community | Surface water |
| Harford Community College - Main Campus | Harford | 2,500 | Non-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, “Gunpowder Falls St Pk Jerusalem Mill, PWSID MD1121239, Maryland”, https://aquacensus.com/water-systems/maryland/gunpowder-falls-st-pk-jerusalem-mill-md1121239 (data as of October 1, 2026).