Public water system · CO0333308
ActiveHalf Moon West Cg
At a glance
Half Moon West Cg (PWSID CO0333308) is an active transient non-community water system in Lake County, Colorado. It reports serving 63 people through 1 service connection. Its primary water source is groundwater, and EPA lists it as owned by the federal government. Of the 12 most recent violations in EPA's records, one is health-based, and the most recent began in October 2020.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
63
Service connections
1
Primary source
GW
Groundwater
System type
TNCWS
Transient non-community water system
System record
How does Half Moon West Cg compare with other water systems in Lake County?
By EPA's size categories, Half Moon West Cg is a very small system (500 people or fewer). Lake County has 19 active public water systems. Its population served is well below the county average of 616 people per system, and accounts for 0.5% of the 11,697 people reported by systems filed under the county. Across Colorado, the 2,207 active systems average 3,400 people each. Nationally, the average active transient non-community water system reports serving 144 people, so Half Moon West Cg is about 56% 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. Colorado has 956 active transient non-community water systems, 43% of the state's 2,207 active systems. Groundwater means the system draws its water from wells or springs fed by underground aquifers. 1,437 Colorado systems (65%) list groundwater as their primary source.
Who owns and regulates Half Moon West Cg?
EPA lists Half Moon West Cg as owned by the federal government. The CO 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 19 active systems in Lake County (26%) are also owned by the federal government.
Does Half Moon West Cg have drinking water violations?
Of the 12 most recent violations in EPA's records, one is health-based, and the most recent began in October 2020. The violations listed here began between September 2006 and October 2020. By type: 5 monitoring and reporting, 3 monitoring, 2 public notice, recordkeeping or other, 1 reporting and 1 required treatment not met. The contaminant or rule involved most often is Revised Total Coliform Rule (5 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 |
|---|---|---|---|---|
| 2020-10-04 | Public notice, recordkeeping or otherPublic Notification Violation for NPDWR Violation · code 75 | Public Noticecode 7500 | No | Resolved |
| 2020-09-01 | MonitoringMonitoring, Routine (RTCR) · code 3A | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2020-07-10 | ReportingReport Startup Procedures Cert Form (RTCR) · code 4C | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2020-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Nitratecode 1040 | No | Resolved |
| 2019-09-01 | MonitoringMonitoring, Routine (RTCR) · code 3A | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2019-08-01 | MonitoringMonitoring, Routine (RTCR) · code 3A | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2016-09-04 | Public notice, recordkeeping or otherPublic Notification Violation for NPDWR Violation · code 75 | Public Noticecode 7500 | No | Resolved |
| 2016-07-11 | Required treatment not metTreatment Technique Startup Procedures (RTCR) · code 2D | Revised Total Coliform Rulecode 8000 | Yes | Resolved |
| 2008-06-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 2007-07-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 2007-05-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 2006-09-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | 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.
Half Moon West Cg: frequently asked questions
Who runs Half Moon West Cg?
Half Moon West Cg (PWSID CO0333308) is a transient non-community water system owned by the federal government. It is regulated by the CO state drinking water program.
How many people does Half Moon West Cg serve?
Half Moon West Cg reports serving 63 people through 1 service connection in Lake County, Colorado.
Where does Half Moon West Cg 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 Half Moon West Cg 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 October 2020. 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 Half Moon West Cg'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 October 2020. For current results, consult EPA ECHO, or the CO state drinking water program.
Where can I find Half Moon West Cg's water quality report?
The annual Consumer Confidence Report requirement applies to community water systems. Half Moon West Cg 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 |
|---|---|---|---|---|
| Parkville Wd | Lake | 7,500 | Community | Surface water |
| Ski Cooper | Lake | 973 | Transient non-community | Groundwater under influence of surface water |
| Climax Climax Mine | Lake | 615 | Non-transient non-community | Surface water |
| White Star Host Site | Lake | 528 | Transient non-community | Groundwater |
| Lake Fork MHP | Lake | 487 | Community | Groundwater |
| Sugar Loafin Rv Campground | Lake | 201 | 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, “Half Moon West Cg, PWSID CO0333308, Colorado”, https://aquacensus.com/water-systems/colorado/half-moon-west-cg-co0333308 (data as of October 1, 2026).