Public water system · MD1040030
ActiveMt. Harmony Elementary School
At a glance
Mt. Harmony Elementary School (PWSID MD1040030) is an active non-transient non-community water system in Calvert County, Maryland. It reports serving 706 people through 1 service connection. Its primary water source is groundwater, and EPA lists it as owned by a local government. EPA's records list 10 violations for this system; 2 are health-based, and the most recent began in October 2010.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
706
Service connections
1
Primary source
GW
Groundwater
System type
NTNCWS
Non-transient non-community water system
System record
How does Mt. Harmony Elementary School compare with other water systems in Calvert County?
By EPA's size categories, Mt. Harmony Elementary School is a small system (501 to 3,300 people). Calvert County has 203 active public water systems. Its population served is about 84% above the county average of 384 people per system, and accounts for 0.9% 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 non-transient non-community water system reports serving 430 people, so Mt. Harmony Elementary School is about 64% above 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. Maryland has 491 active non-transient non-community water systems, 16% 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 Mt. Harmony Elementary School?
EPA lists Mt. Harmony Elementary School 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 Mt. Harmony Elementary School have drinking water violations?
EPA's records list 10 violations for this system; 2 are health-based, and the most recent began in October 2010. The violations listed here began between January 1993 and October 2010. By type: 8 monitoring and reporting and 2 required treatment not met. The contaminant or rule involved most often is Lead and Copper Rule (4 of them). EPA lists 9 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 |
|---|---|---|---|---|
| 2010-10-01 | Monitoring and reportingFollow-up Or Routine LCR Tap M/R · code 52 | Lead and Copper Rulecode 5000 | No | Resolved |
| 1994-01-01 | Required treatment not metPublic Education · code 65 | Lead and Copper Rulecode 5000 | Yes | Resolved |
| 1994-01-01 | Monitoring and reportingInitial, Follow-up, or Routine Source Water M/R · code 56 | Lead and Copper Rulecode 5000 | No | Resolved |
| 1994-01-01 | Required treatment not metOCCT/SOWT Study/Recommendation · code 57 | Lead and Copper Rulecode 5000 | Yes | Resolved |
| 1993-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Cadmiumcode 1015 | No | Resolved |
| 1993-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Bariumcode 1010 | No | Resolved |
| 1993-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Mercurycode 1035 | No | Resolved |
| 1993-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Nitritecode 1041 | No | Archived |
| 1993-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Seleniumcode 1045 | No | Resolved |
| 1993-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Chromiumcode 1020 | No | Resolved |
All 10 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.
Mt. Harmony Elementary School: frequently asked questions
Who runs Mt. Harmony Elementary School?
Mt. Harmony Elementary School (PWSID MD1040030) is a non-transient non-community water system owned by a local government. It is regulated by the MD state drinking water program.
How many people does Mt. Harmony Elementary School serve?
Mt. Harmony Elementary School reports serving 706 people through 1 service connection in Calvert County, Maryland.
Where does Mt. Harmony Elementary School 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 Mt. Harmony Elementary School have any drinking water violations?
EPA's records list 10 violations for this system; 2 are health-based, and the most recent began in October 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 Mt. Harmony Elementary School'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 10 violations for this system; 2 are health-based, and the most recent began in October 2010. For current results, consult EPA ECHO, or the MD state drinking water program.
Where can I find Mt. Harmony Elementary School's water quality report?
The annual Consumer Confidence Report requirement applies to community water systems. Mt. Harmony Elementary School 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 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 |
| Prince Frederick | Calvert | 4,371 | 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 |
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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, “Mt. Harmony Elementary School, PWSID MD1040030, Maryland”, https://aquacensus.com/water-systems/maryland/mt-harmony-elementary-school-md1040030 (data as of October 1, 2026).