Public water system · MT0042665
ActiveLake Mary Ronan State Park
At a glance
Lake Mary Ronan State Park (PWSID MT0042665) is an active transient non-community water system in Lake County, Montana. It reports serving 44 people through 12 service connections. Its primary water source is groundwater, and EPA lists it as owned by a state government. EPA's records list 5 violations for this system; 1 is health-based, and the most recent began in June 2003.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
44
Service connections
12
Primary source
GW
Groundwater
System type
TNCWS
Transient non-community water system
System record
How does Lake Mary Ronan State Park compare with other water systems in Lake County?
By EPA's size categories, Lake Mary Ronan State Park is a very small system (500 people or fewer). Lake County has 90 active public water systems. Its population served is well below the county average of 220 people per system, and accounts for 0.2% of the 19,829 people reported by systems filed under the county. Across Montana, the 2,378 active systems average 489 people each. Nationally, the average active transient non-community water system reports serving 144 people, so Lake Mary Ronan State Park is well 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. Montana has 1,206 active transient non-community water systems, 51% of the state's 2,378 active systems. Groundwater means the system draws its water from wells or springs fed by underground aquifers. 1,994 Montana systems (84%) list groundwater as their primary source.
Who owns and regulates Lake Mary Ronan State Park?
EPA lists Lake Mary Ronan State Park as owned by a state government. The MT state drinking water program is its primacy agency, the regulator with primary enforcement responsibility for the system under the Safe Drinking Water Act. 8 of the 90 active systems in Lake County (8.9%) are also owned by a state government.
Does Lake Mary Ronan State Park have drinking water violations?
EPA's records list 5 violations for this system; 1 is health-based, and the most recent began in June 2003. The violations listed here began between May 1994 and June 2003. By type: 4 monitoring and reporting and 1 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. 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 |
|---|---|---|---|---|
| 2003-06-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 2002-06-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 2001-08-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 1996-09-01 | Monitoring and reportingMonitoring, Routine Minor (TCR) · code 24 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 1994-05-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
All 5 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.
Lake Mary Ronan State Park: frequently asked questions
Who runs Lake Mary Ronan State Park?
Lake Mary Ronan State Park (PWSID MT0042665) is a transient non-community water system owned by a state government. It is regulated by the MT state drinking water program.
How many people does Lake Mary Ronan State Park serve?
Lake Mary Ronan State Park reports serving 44 people through 12 service connections in Lake County, Montana.
Where does Lake Mary Ronan State Park 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 Lake Mary Ronan State Park have any drinking water violations?
EPA's records list 5 violations for this system; 1 is health-based, and the most recent began in June 2003. 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 Lake Mary Ronan State Park'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 5 violations for this system; 1 is health-based, and the most recent began in June 2003. For current results, consult EPA ECHO, or the MT state drinking water program.
Where can I find Lake Mary Ronan State Park's water quality report?
The annual Consumer Confidence Report requirement applies to community water systems. Lake Mary Ronan State Park 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 Lake County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Polson City of | Lake | 5,300 | Community | Groundwater |
| Ronan City of | Lake | 2,483 | Community | Surface water |
| Pablo Lake County Water and Sewer Dist | Lake | 2,175 | Community | Groundwater |
| St Ignatius Town of | Lake | 700 | Community | Groundwater |
| Woods Bay Water and Sewer District | Lake | 685 | Community | Groundwater |
| Wilson Foods | Lake | 600 | 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, “Lake Mary Ronan State Park, PWSID MT0042665, Montana”, https://aquacensus.com/water-systems/montana/lake-mary-ronan-state-park-mt0042665 (data as of October 1, 2026).