Public water system · CO0219117
Active4 Keystones LLC
At a glance
4 Keystones LLC (PWSID CO0219117) is an active transient non-community water system in Eagle County, Colorado. It reports serving 176 people through 20 service connections. Its primary water source is groundwater, and EPA lists it as privately owned. Of the 12 most recent violations in EPA's records, one is health-based, and the most recent began in September 2023.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
176
Service connections
20
Primary source
GW
Groundwater
System type
TNCWS
Transient non-community water system
System record
How does 4 Keystones LLC compare with other water systems in Eagle County?
By EPA's size categories, 4 Keystones LLC is a very small system (500 people or fewer). Eagle County has 46 active public water systems. Its population served is well below the county average of 2,242 people per system, and accounts for 0.2% of the 103,152 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 4 Keystones LLC is about 22% above 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 4 Keystones LLC?
EPA lists 4 Keystones LLC as privately owned. 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. 28 of the 46 active systems in Eagle County (61%) are also privately owned.
Does 4 Keystones LLC have drinking water violations?
Of the 12 most recent violations in EPA's records, one is health-based, and the most recent began in September 2023. The violations listed here began between January 2006 and September 2023. By type: 11 monitoring and reporting and 1 required treatment not met. The contaminant or rule involved most often is Total coliform bacteria (TCR) (8 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 |
|---|---|---|---|---|
| 2023-09-11 | Required treatment not metTreatment Technique Startup Procedures (RTCR) · code 2D | Revised Total Coliform Rulecode 8000 | Yes | Resolved |
| 2012-07-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 2012-04-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 2011-07-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 2009-07-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 2009-04-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 2009-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Nitratecode 1040 | No | Resolved |
| 2008-07-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 2008-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Nitratecode 1040 | No | Resolved |
| 2007-07-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 2006-07-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 2006-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Nitratecode 1040 | 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.
4 Keystones LLC: frequently asked questions
Who runs 4 Keystones LLC?
4 Keystones LLC (PWSID CO0219117) is a transient non-community water system privately owned. It is regulated by the CO state drinking water program.
How many people does 4 Keystones LLC serve?
4 Keystones LLC reports serving 176 people through 20 service connections in Eagle County, Colorado.
Where does 4 Keystones LLC 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 4 Keystones LLC 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 September 2023. 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 4 Keystones LLC'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 September 2023. For current results, consult EPA ECHO, or the CO state drinking water program.
Where can I find 4 Keystones LLC's water quality report?
The annual Consumer Confidence Report requirement applies to community water systems. 4 Keystones LLC 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 Eagle County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Eagle River Wsd | Eagle | 51,515 | Community | Surface water |
| Gypsum Town of | Eagle | 15,272 | Community | Surface water |
| Vail Assoc Midvail Eagle | Eagle | 7,600 | Non-transient non-community | Purchased surface water |
| Eagle Town of | Eagle | 7,511 | Community | Surface water |
| Mid Valley Md | Eagle | 4,588 | Community | Groundwater |
| Basalt Town of | Eagle | 2,357 | Community | Groundwater under influence of surface water |
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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, “4 Keystones LLC, PWSID CO0219117, Colorado”, https://aquacensus.com/water-systems/colorado/4-keystones-llc-co0219117 (data as of October 1, 2026).