Public water system · CO0333305
ActiveHalf Moon East Cg
At a glance
Half Moon East Cg (PWSID CO0333305) is an active transient non-community water system in Lake County, Colorado. It reports serving 128 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; none is health-based, and the most recent began in July 2025.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
128
Service connections
1
Primary source
GW
Groundwater
System type
TNCWS
Transient non-community water system
System record
How does Half Moon East Cg compare with other water systems in Lake County?
By EPA's size categories, Half Moon East 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 1.1% 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 East Cg is about 11% 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 East Cg?
EPA lists Half Moon East 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 East Cg have drinking water violations?
EPA's records list 10 violations for this system; none is health-based, and the most recent began in July 2025. The violations listed here began between January 1993 and July 2025. By type: 6 monitoring and reporting, 2 reporting, 1 public notice, recordkeeping or other and 1 monitoring. The contaminant or rule involved most often is Revised Total Coliform Rule (3 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 |
|---|---|---|---|---|
| 2025-07-11 | ReportingReport Startup Procedures Cert Form (RTCR) · code 4C | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 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 |
| 2002-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Nitratecode 1040 | No | Resolved |
| 1999-04-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 1998-07-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 1998-04-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 1993-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Nitratecode 1040 | 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.
Half Moon East Cg: frequently asked questions
Who runs Half Moon East Cg?
Half Moon East Cg (PWSID CO0333305) 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 East Cg serve?
Half Moon East Cg reports serving 128 people through 1 service connection in Lake County, Colorado.
Where does Half Moon East 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 East Cg have any drinking water violations?
EPA's records list 10 violations for this system; none is health-based, and the most recent began in July 2025. 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 East 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. EPA's records list 10 violations for this system; none is health-based, and the most recent began in July 2025. For current results, consult EPA ECHO, or the CO state drinking water program.
Where can I find Half Moon East Cg's water quality report?
The annual Consumer Confidence Report requirement applies to community water systems. Half Moon East 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 East Cg, PWSID CO0333305, Colorado”, https://aquacensus.com/water-systems/colorado/half-moon-east-cg-co0333305 (data as of October 1, 2026).