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Community Water System · PWS ID7190013

Challis City Of

Challis, Idaho 83226 - drinking water served from surface water sources to 900 people, tracked in EPA SDWIS and UCMR5.

900
People served
191
EPA violations
3
Health-based
Untested
UCMR5 result

The verdict

EPA records 191 drinking-water violations at Challis City Of, 2% of them health-based - above the Idaho per-system average.

191
Total EPA violations on record
2%
Health-based (MCL / treatment failure)
900
People served by this system
N/A
PFAS compounds detected (UCMR5)

Water Quality Snapshot: Challis City Of

Challis City Of is a local-owned community water system that delivers drinking water to 900 residents in Challis, Idaho (Custer County) through 566 service connections. Its water is drawn from surface water sources. EPA's Safe Drinking Water Information System records 191 total violations for this system , of which 3 (2%) are health-based, meaning a contaminant exceeded an EPA Maximum Contaminant Level or a required treatment technique failed. A further 182 monitoring and reporting violations are on file. The most recent violation on record dates to 2024.

The most frequently cited contaminant at this system is CARBON, TOTAL, recorded in 17 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 Idaho, EPA tracks 2,005 public water systems serving 1,743,912 people, with 104,850 cumulative violations and 19,965 health-based violations on record. About 96% of systems in the state carry at least one violation, and state-wide the average per system is 52.3 violations. Statewide, 40 of 60 UCMR5-tested systems have reported PFAS detections (66.7%).

Challis City Of's 191 violations sit above the Idaho 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
900
Total Violations
191
Health-Based Violations
3
Water Source
Surface Water

System Details

System Type
Community
Owner Type
Local
Connections
566
County
Custer
School/Daycare
No
MCL Violations
3
Monitoring Violations
182
Treatment Tech Violations
0

Violation History

Contaminant violations recorded by EPA.

Contaminant Category Count Latest
CARBON, TOTAL MR 17 2024
Nitrate MR 13 2019
Revised Total Coliform Rule MON 12 2024
Coliform (TCR) MR 10 2010
Surface Water Treatment Rule MR 6 2023
Arsenic MR 5 2017
Lead and Copper Rule MR 4 2020
Chromium MR 3 2011
Nickel MR 3 2011
Beryllium, Total MR 3 2011
Selenium MR 3 2011
Fluoride MR 3 2011
1,2,4-Trichlorobenzene MR 3 2019
cis-1,2-Dichloroethylene MR 3 2019
Xylenes, Total MR 3 2019
p-Dichlorobenzene MR 3 2019
Vinyl chloride MR 3 2019
1,1-Dichloroethylene MR 3 2019
1,2-Dichloroethane MR 3 2019
1,1,1-Trichloroethane MR 3 2019
Carbon tetrachloride MR 3 2019
1,2-Dichloropropane MR 3 2019
Trichloroethylene MR 3 2019
Tetrachloroethylene MR 3 2019
CHLOROBENZENE MR 3 2019
Toluene MR 3 2019
Ethylbenzene MR 3 2019
Styrene MR 3 2019
Gross Alpha, Excl. Radon and U MR 3 2017
Interim Enhanced Surface Water Treatment Rule MR 3 2022

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 Challis City 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 ID7190013 on SDWIS

Source: EPA SDWIS Federal Reports Search

State Regulator

Idaho Drinking Water Authority

Idaho's primacy agency administers the Safe Drinking Water Act locally. Search EPA SDWIS for the current state contact, or use the state's public health or environment department portal.

Find ID regulator via EPA SDWIS

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
2024 CARBON, TOTAL MR 17 SDWIS / ID7190013 / 2920
2024 Revised Total Coliform Rule MON 12 SDWIS / ID7190013 / 8000
2023 Surface Water Treatment Rule MR 6 SDWIS / ID7190013 / 0200
2023 Chlorine MR 3 SDWIS / ID7190013 / 0999
2022 Interim Enhanced Surface Water Treatment Rule MR 3 SDWIS / ID7190013 / 0300
2020 Lead and Copper Rule MR 4 SDWIS / ID7190013 / 5000
2019 Nitrate MR 13 SDWIS / ID7190013 / 1040
2019 1,2,4-Trichlorobenzene MR 3 SDWIS / ID7190013 / 2378
2019 cis-1,2-Dichloroethylene MR 3 SDWIS / ID7190013 / 2380
2019 Xylenes, Total MR 3 SDWIS / ID7190013 / 2955
2019 p-Dichlorobenzene MR 3 SDWIS / ID7190013 / 2969
2019 Vinyl chloride MR 3 SDWIS / ID7190013 / 2976
2019 1,1-Dichloroethylene MR 3 SDWIS / ID7190013 / 2977
2019 1,2-Dichloroethane MR 3 SDWIS / ID7190013 / 2980
2019 1,1,1-Trichloroethane MR 3 SDWIS / ID7190013 / 2981

How Challis City Of Compares

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

Metric Challis City Of Idaho avg Federal benchmark
Total violations 191 52.3 SDWA compliance, any non-zero count is a recorded breach
Health-based violations 3 10 Indicates a contaminant exceeded a federal MCL
PFAS detection None 66.7% EPA final rule (2024): PFOA/PFOS MCL = 4.0 ppt
Population served 900 870 Sizing context for compliance burden

Sources: EPA SDWIS and EPA National Primary Drinking Water Regulations (40 CFR Part 141). State averages computed across 2,005 regulated public water systems in Idaho.

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 Challis City Of water safe to drink? ▼
Challis City Of (PWS ID: ID7190013) has 191 recorded violations in the EPA SDWIS database. No PFAS contamination was detected in UCMR5 testing. This system serves 900 people using Surface Water sources.
How many people does Challis City Of serve? ▼
Challis City Of serves 900 people in Challis, Idaho. It is a Local-owned system using Surface Water water sources with 566 service connections.
What type of violations does Challis City Of have? ▼
Challis City Of has 191 total violations: 3 health-based violations (MCL exceedances or treatment failures), 182 monitoring/reporting violations, and 0 treatment technique violations. Health-based violations indicate contaminant levels exceeded EPA safe limits.
Has PFAS been detected in Challis City Of water? ▼
No PFAS testing data is available for Challis City Of under the EPA's UCMR5 monitoring program.
What water source does Challis City Of use? ▼
Challis City 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. 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.