Public water system · MD0180006
ActiveTown of Leonardtown
At a glance
Town of Leonardtown (PWSID MD0180006) is an active community water system in St. Mary's County, Maryland. It reports serving 5,000 people through 1,670 service connections. Its primary water source is groundwater, and EPA lists it as owned by a local government. Of the 12 most recent violations in EPA's records, one is health-based, and the most recent began in January 2024.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
5,000
Service connections
1,670
Primary source
GW
Groundwater
System type
CWS
Community water system
System record
How does Town of Leonardtown compare with other water systems in St. Mary's County?
By EPA's size categories, Town of Leonardtown is a medium system (3,301 to 10,000 people). St. Mary's County has 194 active public water systems, and Town of Leonardtown is the 3rd-largest of them by population served. Its population served is about 7.8 times the county average of 642 people per system, and accounts for 4% of the 124,635 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 Town of Leonardtown is about 25% 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 Town of Leonardtown?
EPA lists Town of Leonardtown 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. 47 of the 194 active systems in St. Mary's County (24%) are also owned by a local government.
Does Town of Leonardtown have drinking water violations?
Of the 12 most recent violations in EPA's records, one is health-based, and the most recent began in January 2024. The violations listed here began between January 2010 and January 2024. By type: 10 monitoring and reporting, 1 contaminant level above the legal limit and 1 public notice, recordkeeping or other. The contaminant or rule involved most often is Lead and Copper Rule (3 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 |
|---|---|---|---|---|
| 2024-01-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Total trihalomethanes (TTHM)code 2950 | No | Resolved |
| 2024-01-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Haloacetic acids (HAA5)code 2456 | No | Resolved |
| 2020-10-01 | Monitoring and reportingFollow-up Or Routine LCR Tap M/R · code 52 | Lead and Copper Rulecode 5000 | No | Resolved |
| 2019-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Nitratecode 1040 | No | Resolved |
| 2017-10-01 | Monitoring and reportingFollow-up Or Routine LCR Tap M/R · code 52 | Lead and Copper Rulecode 5000 | No | Resolved |
| 2016-06-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, E. coli (RTCR) · code 1A | Revised Total Coliform Rulecode 8000 | Yes | Resolved |
| 2011-10-01 | Monitoring and reportingFollow-up Or Routine LCR Tap M/R · code 52 | Lead and Copper Rulecode 5000 | No | Resolved |
| 2010-09-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 2010-07-01 | Public notice, recordkeeping or otherConsumer Confidence Report Complete Failure to Report · code 71 | Consumer Confidence Rulecode 7000 | No | Resolved |
| 2010-01-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 2010-01-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Haloacetic acids (HAA5)code 2456 | No | Resolved |
| 2010-01-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Total trihalomethanes (TTHM)code 2950 | 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.
Town of Leonardtown: frequently asked questions
Who runs Town of Leonardtown?
Town of Leonardtown (PWSID MD0180006) is a community water system owned by a local government. It is regulated by the MD state drinking water program.
How many people does Town of Leonardtown serve?
Town of Leonardtown reports serving 5,000 people through 1,670 service connections in St. Mary's County, Maryland.
Where does Town of Leonardtown 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 Town of Leonardtown 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 January 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 Town of Leonardtown'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 January 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 Town of Leonardtown's water quality report?
As a community water system, Town of Leonardtown 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 St. Mary's County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Lexington Park | St. Mary's | 43,030 | Community | Groundwater |
| Patuxent Naval Air Station (Navfac-Wash) | St. Mary's | 22,000 | Community | Groundwater |
| Country Lakes | St. Mary's | 3,016 | Community | Groundwater |
| Cedar Cove | St. Mary's | 2,728 | Community | Groundwater |
| Saint Marys College | St. Mary's | 2,200 | Community | Groundwater |
| Chopticon High School | St. Mary's | 1,845 | 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, “Town of Leonardtown, PWSID MD0180006, Maryland”, https://aquacensus.com/water-systems/maryland/town-of-leonardtown-md0180006 (data as of October 1, 2026).