PlainWater

Community Water System · PWS CO0111100

Antonito Town Of

Antonito, Colorado 81120 - drinking water served from surface water sources to 981 people, tracked in EPA SDWIS and UCMR5.

981
People served
574
EPA violations
55
Health-based
No PFAS
UCMR5 result

The verdict

EPA records 574 drinking-water violations at Antonito Town Of, 10% of them health-based - above the Colorado per-system average.

574
Total EPA violations on record
10%
Health-based (MCL / treatment failure)
981
People served by this system
0
PFAS compounds detected (UCMR5)

Water Quality Snapshot: Antonito Town Of

Antonito Town Of is a local-owned community water system that delivers drinking water to 981 residents in Antonito, Colorado (Conejos County) through 435 service connections. Its water is drawn from surface water sources. EPA's Safe Drinking Water Information System records 574 total violations for this system , of which 55 (10%) are health-based, meaning a contaminant exceeded an EPA Maximum Contaminant Level or a required treatment technique failed. A further 487 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 Coliform (TCR), recorded in 40 violations (MR). This system was sampled under EPA's UCMR5 PFAS monitoring program and no PFAS compounds were detected above the minimum reporting level.

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%).

Antonito Town Of's 574 violations sit above 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
981
Total Violations
574
Health-Based Violations
55
Water Source
Surface Water

System Details

System Type
Community
Owner Type
Local
Connections
435
County
Conejos
School/Daycare
No
MCL Violations
4
Monitoring Violations
487
Treatment Tech Violations
51

Violation History

Contaminant violations recorded by EPA.

Contaminant Category Count Latest
Coliform (TCR) MR 40 2013
Chlorine MR 38 2025
Lead and Copper Rule MR 30 2020
Surface Water Treatment Rule MR 28 2025
Total Haloacetic Acids (HAA5) MR 26 2020
TTHM MR 26 2020
Public Notice Other 23 2022
Surface Water Treatment Rule TT 21 2018
Revised Total Coliform Rule MON 16 2025
CARBON, TOTAL MR 14 2024
Stage 1 Disinfectants and Disinfection Byproducts Rule TT 12 2018
Nitrate MR 11 2012
Groundwater Rule TT 9 2018
Xylenes, Total MR 6 2020
DICHLOROMETHANE MR 6 2020
o-Dichlorobenzene MR 6 2020
Vinyl chloride MR 6 2020
1,1,1-Trichloroethane MR 6 2020
Carbon tetrachloride MR 6 2020
1,2-Dichloropropane MR 6 2020
Trichloroethylene MR 6 2020
1,1,2-Trichloroethane MR 6 2020
Benzene MR 6 2020
Interim Enhanced Surface Water Treatment Rule MR 6 2022
p-Dichlorobenzene MR 6 2020
1,1-Dichloroethylene MR 6 2020
trans-1,2-Dichloroethylene MR 6 2020
1,2-Dichloroethane MR 6 2020
CHLOROBENZENE MR 6 2020
Ethylbenzene MR 6 2020

PFAS Testing Results (UCMR5)

Results from EPA's Fifth Unregulated Contaminant Monitoring Rule. 0 of 116 samples detected PFAS.

Contaminant Date Result MRL Status
PFEESA 9/12/2024 <3.00 ppt 3.00 ppt Not Detected
PFUnA 9/12/2024 <2.00 ppt 2.00 ppt Not Detected
11Cl-PF3OUdS 9/12/2024 <5.00 ppt 5.00 ppt Not Detected
9Cl-PF3ONS 9/12/2024 <2.00 ppt 2.00 ppt Not Detected
ADONA 9/12/2024 <3.00 ppt 3.00 ppt Not Detected
HFPO-DA 9/12/2024 <5.00 ppt 5.00 ppt Not Detected
PFTrDA 9/12/2024 <7.00 ppt 7.00 ppt Not Detected
PFPeS 9/12/2024 <4.00 ppt 4.00 ppt Not Detected
PFMBA 9/12/2024 <3.00 ppt 3.00 ppt Not Detected
NFDHA 9/12/2024 <20.00 ppt 20.00 ppt Not Detected
PFHxA 9/12/2024 <3.00 ppt 3.00 ppt Not Detected
PFPeA 9/12/2024 <3.00 ppt 3.00 ppt Not Detected
PFHpS 9/12/2024 <3.00 ppt 3.00 ppt Not Detected
PFBA 9/12/2024 <5.00 ppt 5.00 ppt Not Detected
PFDoA 9/12/2024 <3.00 ppt 3.00 ppt Not Detected
PFDA 9/12/2024 <3.00 ppt 3.00 ppt Not Detected
PFOA 9/12/2024 <4.00 ppt 4.00 ppt Not Detected
PFOS 9/12/2024 <4.00 ppt 4.00 ppt Not Detected
PFNA 9/12/2024 <4.00 ppt 4.00 ppt Not Detected
PFHxS 9/12/2024 <3.00 ppt 3.00 ppt Not Detected
PFBS 9/12/2024 <3.00 ppt 3.00 ppt Not Detected
PFMPA 9/12/2024 <4.00 ppt 4.00 ppt Not Detected
8:2 FTS 9/12/2024 <5.00 ppt 5.00 ppt Not Detected
4:2 FTS 9/12/2024 <3.00 ppt 3.00 ppt Not Detected
6:2 FTS 9/12/2024 <5.00 ppt 5.00 ppt Not Detected
PFTA 9/12/2024 <8.00 ppt 8.00 ppt Not Detected
PFHpA 9/12/2024 <3.00 ppt 3.00 ppt Not Detected
NEtFOSAA 9/12/2024 <5.00 ppt 5.00 ppt Not Detected
NMeFOSAA 9/12/2024 <6.00 ppt 6.00 ppt Not Detected
4:2 FTS 5/7/2024 <3.00 ppt 3.00 ppt Not Detected
6:2 FTS 5/7/2024 <5.00 ppt 5.00 ppt Not Detected
PFBA 5/7/2024 <5.00 ppt 5.00 ppt Not Detected
HFPO-DA 5/7/2024 <5.00 ppt 5.00 ppt Not Detected
ADONA 5/7/2024 <3.00 ppt 3.00 ppt Not Detected
9Cl-PF3ONS 5/7/2024 <2.00 ppt 2.00 ppt Not Detected
8:2 FTS 5/7/2024 <5.00 ppt 5.00 ppt Not Detected
PFUnA 5/7/2024 <2.00 ppt 2.00 ppt Not Detected
PFDA 5/7/2024 <3.00 ppt 3.00 ppt Not Detected
PFHxA 5/7/2024 <3.00 ppt 3.00 ppt Not Detected
PFDoA 5/7/2024 <3.00 ppt 3.00 ppt Not Detected
PFNA 5/7/2024 <4.00 ppt 4.00 ppt Not Detected
NMeFOSAA 5/7/2024 <6.00 ppt 6.00 ppt Not Detected
PFTrDA 5/7/2024 <7.00 ppt 7.00 ppt Not Detected
PFTA 5/7/2024 <8.00 ppt 8.00 ppt Not Detected
11Cl-PF3OUdS 5/7/2024 <5.00 ppt 5.00 ppt Not Detected
PFOA 5/7/2024 <4.00 ppt 4.00 ppt Not Detected
NEtFOSAA 5/7/2024 <5.00 ppt 5.00 ppt Not Detected
PFMPA 5/7/2024 <4.00 ppt 4.00 ppt Not Detected
PFOS 5/7/2024 <4.00 ppt 4.00 ppt Not Detected
PFHxS 5/7/2024 <3.00 ppt 3.00 ppt Not Detected

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 Antonito Town Of.

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 CO0111100 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 Antonito Town Of 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 Chlorine MR 38 SDWIS / CO0111100 / 0999
2025 Surface Water Treatment Rule MR 28 SDWIS / CO0111100 / 0200
2025 Revised Total Coliform Rule MON 16 SDWIS / CO0111100 / 8000
2024 CARBON, TOTAL MR 14 SDWIS / CO0111100 / 2920
2022 Public Notice Other 23 SDWIS / CO0111100 / 7500
2022 Interim Enhanced Surface Water Treatment Rule MR 6 SDWIS / CO0111100 / 0300
2020 Lead and Copper Rule MR 30 SDWIS / CO0111100 / 5000
2020 Total Haloacetic Acids (HAA5) MR 26 SDWIS / CO0111100 / 2456
2020 TTHM MR 26 SDWIS / CO0111100 / 2950
2020 Xylenes, Total MR 6 SDWIS / CO0111100 / 2955
2020 DICHLOROMETHANE MR 6 SDWIS / CO0111100 / 2964
2020 o-Dichlorobenzene MR 6 SDWIS / CO0111100 / 2968
2020 Vinyl chloride MR 6 SDWIS / CO0111100 / 2976
2020 1,1,1-Trichloroethane MR 6 SDWIS / CO0111100 / 2981
2020 Carbon tetrachloride MR 6 SDWIS / CO0111100 / 2982

How Antonito Town Of Compares

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

Metric Antonito Town Of Colorado avg Federal benchmark
Total violations 574 108.9 SDWA compliance, any non-zero count is a recorded breach
Health-based violations 55 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 981 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 Antonito Town Of water safe to drink?
Antonito Town Of (PWS ID: CO0111100) has 574 recorded violations in the EPA SDWIS database. No PFAS contamination was detected in UCMR5 testing. This system serves 981 people using Surface Water sources.
How many people does Antonito Town Of serve?
Antonito Town Of serves 981 people in Antonito, Colorado. It is a Local-owned system using Surface Water water sources with 435 service connections.
What type of violations does Antonito Town Of have?
Antonito Town Of has 574 total violations: 55 health-based violations (MCL exceedances or treatment failures), 487 monitoring/reporting violations, and 51 treatment technique violations. Health-based violations indicate contaminant levels exceeded EPA safe limits.
Has PFAS been detected in Antonito Town Of water?
No. Antonito Town Of was tested for PFAS under the EPA's UCMR5 monitoring program and no PFAS contamination was detected.
What water source does Antonito Town Of use?
Antonito Town Of uses Surface Water as its primary water source. It is classified as a Community Water System (CWS), serving residential populations year-round.
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. PFAS data from EPA UCMR5 monitoring program (2023-2025). This data is provided for informational purposes only.
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.