Public water system · CO0157250
ActiveIlium Valley Ws
At a glance
Ilium Valley Ws (PWSID CO0157250) is an active community water system in San Miguel County, Colorado. It reports serving 322 people through 74 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 January 2026.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
322
Service connections
74
Primary source
GW
Groundwater
System type
CWS
Community water system
System record
How does Ilium Valley Ws compare with other water systems in San Miguel County?
By EPA's size categories, Ilium Valley Ws is a very small system (500 people or fewer). San Miguel County has 20 active public water systems, and Ilium Valley Ws is the 6th-largest of them by population served. Its population served is well below the county average of 1,103 people per system, and accounts for 1.5% of the 22,054 people reported by systems filed under the county. Across Colorado, the 2,207 active systems average 3,400 people each. Nationally, the average active community water system reports serving 6,703 people, so Ilium Valley Ws is well below that figure.
What does “community water system” mean?
A community water system serves at least 15 connections used by year-round residents, or regularly serves at least 25 year-round residents. Homes, apartments and mobile-home parks are served by these. Colorado has 1,068 active community water systems, 48% 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 Ilium Valley Ws?
EPA lists Ilium Valley Ws 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. 10 of the 20 active systems in San Miguel County (50%) are also privately owned.
Does Ilium Valley Ws have drinking water violations?
Of the 12 most recent violations in EPA's records, one is health-based, and the most recent began in January 2026. The violations listed here began between April 2014 and January 2026. By type: 7 monitoring and reporting, 2 monitoring, 2 public notice, recordkeeping or other and 1 required treatment not met. The contaminant or rule involved most often is Chlorine (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 |
|---|---|---|---|---|
| 2026-01-01 | MonitoringMonitoring, Routine (RTCR) · code 3A | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2026-01-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Chlorinecode 0999 | No | Resolved |
| 2023-10-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Chlorinecode 0999 | No | Resolved |
| 2018-11-06 | Public notice, recordkeeping or otherPublic Notification Violation without NPDWR Violation · code 76 | Public Noticecode 7500 | No | Resolved |
| 2017-11-01 | MonitoringMonitoring, Routine (RTCR) · code 3A | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2017-10-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Chlorinecode 0999 | No | Resolved |
| 2016-07-01 | Public notice, recordkeeping or otherConsumer Confidence Report Complete Failure to Report · code 71 | Consumer Confidence Rulecode 7000 | No | Resolved |
| 2016-03-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 2015-07-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Chlorinecode 0999 | No | Resolved |
| 2015-01-01 | Required treatment not metTreatment Technique No Certif. Operator · code 12 | Stage 1 Disinfectants and Disinfection Byproducts Rulecode 0400 | Yes | Resolved |
| 2014-04-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 2014-04-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Chlorinecode 0999 | 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.
Ilium Valley Ws: frequently asked questions
Who runs Ilium Valley Ws?
Ilium Valley Ws (PWSID CO0157250) is a community water system privately owned. It is regulated by the CO state drinking water program.
How many people does Ilium Valley Ws serve?
Ilium Valley Ws reports serving 322 people through 74 service connections in San Miguel County, Colorado.
Where does Ilium Valley Ws 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 Ilium Valley Ws 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 January 2026. 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 Ilium Valley Ws' 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 January 2026. For current results, consult the system's annual water quality report, EPA ECHO, or the CO state drinking water program.
Where can I find Ilium Valley Ws' water quality report?
As a community water system, Ilium Valley Ws must deliver an annual water quality report, called a Consumer Confidence Report, to its customers by July 1 each year, covering the previous calendar year. The system can provide a copy on request.
Other water systems in San Miguel County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Mountain Village Town of | San Miguel | 9,700 | Community | Groundwater |
| Telluride Town of | San Miguel | 7,900 | Community | Surface water |
| Norwood Water Commission | San Miguel | 1,700 | Community | Surface water |
| Telluride Regional Airport | San Miguel | 485 | Transient non-community | Groundwater |
| Aldasoro Ranch Hoc | San Miguel | 412 | Community | Groundwater |
| Wilson Mesa | San Miguel | 290 | Community | 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, “Ilium Valley Ws, PWSID CO0157250, Colorado”, https://aquacensus.com/water-systems/colorado/ilium-valley-ws-co0157250 (data as of October 1, 2026).