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Community Water System · PWS IL0130010

Calhoun County RWD

Hardin, Illinois 62047 - drinking water served from groundwater sources to 4,675 people, tracked in EPA SDWIS and UCMR5.

4,675
People served
30
EPA violations
6
Health-based
No PFAS
UCMR5 result

The verdict

EPA records 30 drinking-water violations at Calhoun County RWD, 20% of them health-based - below the Illinois per-system average.

30
Total EPA violations on record
20%
Health-based (MCL / treatment failure)
4,675
People served by this system
0
PFAS compounds detected (UCMR5)

Water Quality Snapshot: Calhoun County RWD

Calhoun County RWD is a local-owned community water system that delivers drinking water to 4,675 residents in Hardin, Illinois (Calhoun County) through 1,771 service connections. Its water is drawn from groundwater sources. EPA's Safe Drinking Water Information System records 30 total violations for this system , of which 6 (20%) are health-based, meaning a contaminant exceeded an EPA Maximum Contaminant Level or a required treatment technique failed. A further 22 monitoring and reporting violations are on file. The most recent violation on record dates to 2020.

The most frequently cited contaminant at this system is Chlorine, recorded in 10 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 Illinois, EPA tracks 5,117 public water systems serving 12,576,876 people, with 355,322 cumulative violations and 52,932 health-based violations on record. About 81% of systems in the state carry at least one violation, and state-wide the average per system is 69.4 violations. Statewide, 199 of 487 UCMR5-tested systems have reported PFAS detections (40.9%).

Calhoun County RWD's 30 violations sit below the Illinois 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
4,675
Total Violations
30
Health-Based Violations
6
Water Source
Groundwater

System Details

System Type
Community
Owner Type
Local
Connections
1,771
County
Calhoun
School/Daycare
No
MCL Violations
6
Monitoring Violations
22
Treatment Tech Violations
0

Violation History

Contaminant violations recorded by EPA.

Contaminant Category Count Latest
Chlorine MR 10 2008
Coliform (TCR) MR 9 2007
TTHM MCL 6 2020
Nitrate MR 3 2002
Public Notice Other 2 2020

PFAS Testing Results (UCMR5)

Results from EPA's Fifth Unregulated Contaminant Monitoring Rule. 0 of 58 samples detected PFAS.

Contaminant Date Result MRL Status
8:2 FTS 6/18/2025 <5.00 ppt 5.00 ppt Not Detected
4:2 FTS 6/18/2025 <3.00 ppt 3.00 ppt Not Detected
6:2 FTS 6/18/2025 <5.00 ppt 5.00 ppt Not Detected
PFMPA 6/18/2025 <4.00 ppt 4.00 ppt Not Detected
PFPeA 6/18/2025 <3.00 ppt 3.00 ppt Not Detected
PFMBA 6/18/2025 <3.00 ppt 3.00 ppt Not Detected
PFEESA 6/18/2025 <3.00 ppt 3.00 ppt Not Detected
NFDHA 6/18/2025 <20.00 ppt 20.00 ppt Not Detected
PFPeS 6/18/2025 <4.00 ppt 4.00 ppt Not Detected
PFHpS 6/18/2025 <3.00 ppt 3.00 ppt Not Detected
PFTA 6/18/2025 <8.00 ppt 8.00 ppt Not Detected
PFTrDA 6/18/2025 <7.00 ppt 7.00 ppt Not Detected
PFBA 6/18/2025 <5.00 ppt 5.00 ppt Not Detected
NMeFOSAA 6/18/2025 <6.00 ppt 6.00 ppt Not Detected
PFNA 6/18/2025 <4.00 ppt 4.00 ppt Not Detected
NEtFOSAA 6/18/2025 <5.00 ppt 5.00 ppt Not Detected
PFBS 6/18/2025 <3.00 ppt 3.00 ppt Not Detected
PFOA 6/18/2025 <4.00 ppt 4.00 ppt Not Detected
HFPO-DA 6/18/2025 <5.00 ppt 5.00 ppt Not Detected
PFHpA 6/18/2025 <3.00 ppt 3.00 ppt Not Detected
PFHxS 6/18/2025 <3.00 ppt 3.00 ppt Not Detected
PFOS 6/18/2025 <4.00 ppt 4.00 ppt Not Detected
PFDA 6/18/2025 <3.00 ppt 3.00 ppt Not Detected
PFDoA 6/18/2025 <3.00 ppt 3.00 ppt Not Detected
PFHxA 6/18/2025 <3.00 ppt 3.00 ppt Not Detected
PFUnA 6/18/2025 <2.00 ppt 2.00 ppt Not Detected
11Cl-PF3OUdS 6/18/2025 <5.00 ppt 5.00 ppt Not Detected
9Cl-PF3ONS 6/18/2025 <2.00 ppt 2.00 ppt Not Detected
ADONA 6/18/2025 <3.00 ppt 3.00 ppt Not Detected
PFEESA 11/3/2025 <3.00 ppt 3.00 ppt Not Detected
8:2 FTS 11/3/2025 <5.00 ppt 5.00 ppt Not Detected
ADONA 11/3/2025 <3.00 ppt 3.00 ppt Not Detected
HFPO-DA 11/3/2025 <5.00 ppt 5.00 ppt Not Detected
PFBA 11/3/2025 <5.00 ppt 5.00 ppt Not Detected
6:2 FTS 11/3/2025 <5.00 ppt 5.00 ppt Not Detected
4:2 FTS 11/3/2025 <3.00 ppt 3.00 ppt Not Detected
9Cl-PF3ONS 11/3/2025 <2.00 ppt 2.00 ppt Not Detected
PFMPA 11/3/2025 <4.00 ppt 4.00 ppt Not Detected
NEtFOSAA 11/3/2025 <5.00 ppt 5.00 ppt Not Detected
11Cl-PF3OUdS 11/3/2025 <5.00 ppt 5.00 ppt Not Detected
PFHpS 11/3/2025 <3.00 ppt 3.00 ppt Not Detected
PFMBA 11/3/2025 <3.00 ppt 3.00 ppt Not Detected
NFDHA 11/3/2025 <20.00 ppt 20.00 ppt Not Detected
PFPeS 11/3/2025 <4.00 ppt 4.00 ppt Not Detected
PFPeA 11/3/2025 <3.00 ppt 3.00 ppt Not Detected
PFHpA 11/3/2025 <3.00 ppt 3.00 ppt Not Detected
PFTA 11/3/2025 <8.00 ppt 8.00 ppt Not Detected
PFUnA 11/3/2025 <2.00 ppt 2.00 ppt Not Detected
NMeFOSAA 11/3/2025 <6.00 ppt 6.00 ppt Not Detected
PFHxS 11/3/2025 <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 Calhoun County RWD.

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 IL0130010 on SDWIS

Source: EPA SDWIS Federal Reports Search

State Regulator

Illinois Drinking Water Authority

Illinois EPA, Bureau of Water is the primacy agency that licenses and inspects Calhoun County RWD under EPA-delegated authority.

Open IL regulator portal

Source: Illinois EPA, Bureau of Water

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
2020 TTHM MCL 6 SDWIS / IL0130010 / 2950
2020 Public Notice Other 2 SDWIS / IL0130010 / 7500
2008 Chlorine MR 10 SDWIS / IL0130010 / 0999
2007 Coliform (TCR) MR 9 SDWIS / IL0130010 / 3100
2002 Nitrate MR 3 SDWIS / IL0130010 / 1040

How Calhoun County RWD Compares

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

Metric Calhoun County RWD Illinois avg Federal benchmark
Total violations 30 69.4 SDWA compliance, any non-zero count is a recorded breach
Health-based violations 6 10.3 Indicates a contaminant exceeded a federal MCL
PFAS detection None 40.9% EPA final rule (2024): PFOA/PFOS MCL = 4.0 ppt
Population served 4,675 2,458 Sizing context for compliance burden

Sources: EPA SDWIS and EPA National Primary Drinking Water Regulations (40 CFR Part 141). State averages computed across 5,117 regulated public water systems in Illinois.

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 Calhoun County RWD water safe to drink?
Calhoun County RWD (PWS ID: IL0130010) has 30 recorded violations in the EPA SDWIS database. No PFAS contamination was detected in UCMR5 testing. This system serves 4,675 people using Groundwater sources.
How many people does Calhoun County RWD serve?
Calhoun County RWD serves 4,675 people in Hardin, Illinois. It is a Local-owned system using Groundwater water sources with 1,771 service connections.
What type of violations does Calhoun County RWD have?
Calhoun County RWD has 30 total violations: 6 health-based violations (MCL exceedances or treatment failures), 22 monitoring/reporting violations, and 0 treatment technique violations. Health-based violations indicate contaminant levels exceeded EPA safe limits.
Has PFAS been detected in Calhoun County RWD water?
No. Calhoun County RWD was tested for PFAS under the EPA's UCMR5 monitoring program and no PFAS contamination was detected.
What water source does Calhoun County RWD use?
Calhoun County RWD uses Groundwater 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.