Public water system · MT0062227
ActiveGreenough Lake Cg Well No 1
At a glance
Greenough Lake Cg Well No 1 (PWSID MT0062227) is an active transient non-community water system in Carbon County, Montana. It reports serving 50 people through 1 service connection. Its primary water source is groundwater, and EPA lists it as owned by the federal government. EPA's records list 10 violations for this system; 2 are health-based, and the most recent began in January 2022.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
50
Service connections
1
Primary source
GW
Groundwater
System type
TNCWS
Transient non-community water system
System record
How does Greenough Lake Cg Well No 1 compare with other water systems in Carbon County?
By EPA's size categories, Greenough Lake Cg Well No 1 is a very small system (500 people or fewer). Carbon County has 36 active public water systems. Its population served is well below the county average of 253 people per system, and accounts for 0.5% of the 9,106 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 Greenough Lake Cg Well No 1 is about 65% 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 Greenough Lake Cg Well No 1?
EPA lists Greenough Lake Cg Well No 1 as owned by the federal 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. 5 of the 36 active systems in Carbon County (14%) are also owned by the federal government.
Does Greenough Lake Cg Well No 1 have drinking water violations?
EPA's records list 10 violations for this system; 2 are health-based, and the most recent began in January 2022. The violations listed here began between August 1994 and January 2022. By type: 8 monitoring and reporting and 2 contaminant level above the legal limit. The contaminant or rule involved most often is Total coliform bacteria (TCR) (8 of them). EPA lists 10 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 |
|---|---|---|---|---|
| 2022-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Nitrate-Nitritecode 1038 | No | Resolved |
| 2012-07-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 2009-06-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 2005-10-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 2003-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Nitrate-Nitritecode 1038 | No | Resolved |
| 2000-09-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 2000-08-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 1995-07-01 | Monitoring and reportingMonitoring, Repeat Minor (TCR) · code 26 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 1995-07-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
| 1994-08-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | 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.
Greenough Lake Cg Well No 1: frequently asked questions
Who runs Greenough Lake Cg Well No 1?
Greenough Lake Cg Well No 1 (PWSID MT0062227) is a transient non-community water system owned by the federal government. It is regulated by the MT state drinking water program.
How many people does Greenough Lake Cg Well No 1 serve?
Greenough Lake Cg Well No 1 reports serving 50 people through 1 service connection in Carbon County, Montana.
Where does Greenough Lake Cg Well No 1 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 Greenough Lake Cg Well No 1 have any drinking water violations?
EPA's records list 10 violations for this system; 2 are health-based, and the most recent began in January 2022. 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 Greenough Lake Cg Well No 1'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 January 2022. For current results, consult EPA ECHO, or the MT state drinking water program.
Where can I find Greenough Lake Cg Well No 1's water quality report?
The annual Consumer Confidence Report requirement applies to community water systems. Greenough Lake Cg Well No 1 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 Carbon County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Red Lodge Mtn Main Lodge | Carbon | 2,006 | Transient non-community | Groundwater |
| Red Lodge Water Dept | Carbon | 2,000 | Community | Groundwater |
| Bridger Town of | Carbon | 750 | Community | Groundwater |
| Joliet Town of | Carbon | 600 | Community | Groundwater |
| Fromberg Town of | Carbon | 498 | Community | Groundwater |
| Bridger Rest Area | Carbon | 400 | 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, “Greenough Lake Cg Well No 1, PWSID MT0062227, Montana”, https://aquacensus.com/water-systems/montana/greenough-lake-cg-well-no-1-mt0062227 (data as of October 1, 2026).