Public water system · CO0335343
ActiveHidden Valley
At a glance
Hidden Valley (PWSID CO0335343) is an active transient non-community water system in Larimer County, Colorado. It reports serving 250 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 one violation for this system; it is not health-based, and the most recent began in April 1994.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
250
Service connections
1
Primary source
GW
Groundwater
System type
TNCWS
Transient non-community water system
System record
How does Hidden Valley compare with other water systems in Larimer County?
By EPA's size categories, Hidden Valley is a very small system (500 people or fewer). Larimer County has 134 active public water systems. Its population served is well below the county average of 3,842 people per system, and accounts for less than 0.1% of the 514,860 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 Hidden Valley is about 74% 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 Hidden Valley?
EPA lists Hidden Valley 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. 26 of the 134 active systems in Larimer County (19%) are also owned by the federal government.
Does Hidden Valley have drinking water violations?
EPA's records list one violation for this system; it is not health-based, and the most recent began in April 1994. By type: 1 monitoring and reporting. The contaminant or rule involved is Surface Water Treatment Rule. EPA lists 1 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 |
|---|---|---|---|---|
| 1994-04-01 | Monitoring and reportingMonitoring of Treatment (SWTR-Filter) · code 36 | Surface Water Treatment Rulecode 0200 | No | Resolved |
The one violation in EPA's records.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.
Hidden Valley: frequently asked questions
Who runs Hidden Valley?
Hidden Valley (PWSID CO0335343) 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 Hidden Valley serve?
Hidden Valley reports serving 250 people through 1 service connection in Larimer County, Colorado.
Where does Hidden Valley 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 Hidden Valley have any drinking water violations?
EPA's records list one violation for this system; it is not health-based, and the most recent began in April 1994. 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 Hidden Valley'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 one violation for this system; it is not health-based, and the most recent began in April 1994. For current results, consult EPA ECHO, or the CO state drinking water program.
Where can I find Hidden Valley's water quality report?
The annual Consumer Confidence Report requirement applies to community water systems. Hidden Valley 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 Larimer County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Ft Collins City of | Larimer | 179,901 | Community | Surface water |
| Loveland City of | Larimer | 91,077 | Community | Surface water |
| Ft Collins Loveland Wd | Larimer | 63,532 | Community | Purchased surface water |
| East Larimer County Wd | Larimer | 27,944 | Community | Purchased surface water |
| Csu Main and West Housing Campus | Larimer | 27,375 | Community | Purchased surface water |
| Little Thompson Wd | Larimer | 25,654 | Community | Purchased 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, “Hidden Valley, PWSID CO0335343, Colorado”, https://aquacensus.com/water-systems/colorado/hidden-valley-co0335343 (data as of October 1, 2026).