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States → Colorado

Transient Non-Community Water System · PWS CO0357500

Matterhorn Cg

Delta, Colorado 81416 - drinking water served from groundwater sources to 50 people, tracked in EPA SDWIS and UCMR5.

50
People served
89
EPA violations
28
Health-based
Untested
UCMR5 result

The verdict

EPA records 89 drinking-water violations at Matterhorn Cg, 31% of them health-based - below the Colorado per-system average.

89
Total EPA violations on record
31%
Health-based (MCL / treatment failure)
50
People served by this system
N/A
PFAS compounds detected (UCMR5)

Water Quality Snapshot: Matterhorn Cg

Matterhorn Cg is a federal-owned transient non-community water system that delivers drinking water to 50 residents in Delta, Colorado (San Miguel County) through 15 service connections. Its water is drawn from groundwater sources. EPA's Safe Drinking Water Information System records 89 total violations for this system , of which 28 (31%) are health-based, meaning a contaminant exceeded an EPA Maximum Contaminant Level or a required treatment technique failed. A further 58 monitoring and reporting violations are on file. The most recent violation on record dates to 2025.

The most frequently cited contaminant at this system is Surface Water Treatment Rule, recorded in 31 violations (MR). This system has not yet been sampled under EPA's UCMR5 PFAS monitoring program, so no PFAS detection data is available here.

Across Colorado, EPA tracks 2,193 public water systems serving 7,473,456 people, with 238,796 cumulative violations and 30,589 health-based violations on record. About 93% of systems in the state carry at least one violation, and state-wide the average per system is 108.9 violations. Statewide, 98 of 163 UCMR5-tested systems have reported PFAS detections (60.1%).

Matterhorn Cg's 89 violations sit below the Colorado average.

All figures above are sourced directly from EPA SDWIS and UCMR5 public data releases and are updated as EPA publishes new reporting cycles.

Population Served
50
Total Violations
89
Health-Based Violations
28
Water Source
Groundwater

System Details

System Type
Transient Non-Community
Owner Type
Federal
Connections
15
County
San Miguel
School/Daycare
No
MCL Violations
0
Monitoring Violations
58
Treatment Tech Violations
28

Violation History

Contaminant violations recorded by EPA.

Contaminant Category Count Latest
Surface Water Treatment Rule MR 31 2019
Surface Water Treatment Rule TT 28 2016
Interim Enhanced Surface Water Treatment Rule MR 24 2019
Coliform (TCR) MR 3 2004
Revised Total Coliform Rule RPT 3 2025

Verify This Water System

The figures above are aggregated from EPA's public databases. To verify the underlying records, or to file a complaint, request a Consumer Confidence Report, or check current monitoring status, go directly to the federal and state regulators that enforce the Safe Drinking Water Act for Matterhorn Cg.

Federal Source of Truth

EPA SDWIS, Federal Reports

EPA's Safe Drinking Water Information System (SDWIS) holds the federal compliance record for every regulated public water system. Open the system-level report by PWS ID:

View PWS ID CO0357500 on SDWIS

Source: EPA SDWIS Federal Reports Search

State Regulator

Colorado Drinking Water Authority

Colorado Department of Public Health and Environment, Water Quality Control is the primacy agency that licenses and inspects Matterhorn Cg under EPA-delegated authority.

Open CO regulator portal

Source: Colorado Department of Public Health and Environment, Water Quality Control

Violation Timeline

Each row links to the EPA SDWIS public record for verification. Cross-reference the contaminant code on EPA's federal report to see violation dates, return-to-compliance status, and enforcement actions.

Year (latest) Contaminant Category Count EPA Record
2025 Revised Total Coliform Rule RPT 3 SDWIS / CO0357500 / 8000
2019 Surface Water Treatment Rule MR 31 SDWIS / CO0357500 / 0200
2019 Interim Enhanced Surface Water Treatment Rule MR 24 SDWIS / CO0357500 / 0300
2016 Surface Water Treatment Rule TT 28 SDWIS / CO0357500 / 0200
2004 Coliform (TCR) MR 3 SDWIS / CO0357500 / 3100

How Matterhorn Cg Compares

Cross-reference this system's record against state averages and the federal MCL framework for context.

Metric Matterhorn Cg Colorado avg Federal benchmark
Total violations 89 108.9 SDWA compliance, any non-zero count is a recorded breach
Health-based violations 28 13.9 Indicates a contaminant exceeded a federal MCL
PFAS detection None 60.1% EPA final rule (2024): PFOA/PFOS MCL = 4.0 ppt
Population served 50 3,408 Sizing context for compliance burden

Sources: EPA SDWIS and EPA National Primary Drinking Water Regulations (40 CFR Part 141). State averages computed across 2,193 regulated public water systems in Colorado.

Federal MCL reference, Safe Drinking Water Act thresholds ▼
Contaminant Federal MCL / Action Level Note
Lead 0 mg/L (Action Level: 0.015 mg/L) Lead and Copper Rule treatment technique
Arsenic 0.010 mg/L (10 ppb) Health-based MCL since 2006
Total Coliform Treatment technique (RTCR) Indicator organism, monitoring trigger
PFOA / PFOS (PFAS) 4.0 ppt each (final 2024 rule) Compliance deadline 2029 (EPA proposed extending to 2031, not yet final as of May 2026)
Nitrate (as N) 10 mg/L Acute health risk for infants

Frequently Asked Questions

Is Matterhorn Cg water safe to drink? ▼
Matterhorn Cg (PWS ID: CO0357500) has 89 recorded violations in the EPA SDWIS database. No PFAS contamination was detected in UCMR5 testing. This system serves 50 people using Groundwater sources.
How many people does Matterhorn Cg serve? ▼
Matterhorn Cg serves 50 people in Delta, Colorado. It is a Federal-owned system using Groundwater water sources with 15 service connections.
What type of violations does Matterhorn Cg have? ▼
Matterhorn Cg has 89 total violations: 28 health-based violations (MCL exceedances or treatment failures), 58 monitoring/reporting violations, and 28 treatment technique violations. Health-based violations indicate contaminant levels exceeded EPA safe limits.
Has PFAS been detected in Matterhorn Cg water? ▼
No PFAS testing data is available for Matterhorn Cg under the EPA's UCMR5 monitoring program.
What water source does Matterhorn Cg use? ▼
Matterhorn Cg uses Groundwater as its primary water source. It is classified as a Transient Non-Community Water System, serving transient populations.
Where does this data come from? ▼
All data comes from the EPA Safe Drinking Water Information System (SDWIS) and the UCMR5 PFAS monitoring program. SDWIS tracks compliance for all public water systems regulated under the Safe Drinking Water Act.
Data Sources: EPA Safe Drinking Water Information System (SDWIS), Q4 2025. This data is provided for informational purposes only.

Read our methodology - how this data is sourced, computed, and verified.

Data sourced from EPA SDWIS and UCMR5 PFAS monitoring data. See our methodology for details. Retrieved and formatted by PlainWater Editorial

Every figure on PlainWater is rendered directly from EPA SDWIS drinking-water data, no number is typed in by an editor. This system's figures are rendered directly from EPA SDWIS data, no figure is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error.