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ONAWA MUNICIPAL WATER PLANT

PWS ID: IA6739095 · ONAWA, Iowa 51040

ONAWA MUNICIPAL WATER PLANT serves 2,906 people in ONAWA, Iowa using Groundwater water sources. It has 3 recorded EPA violations, including 0 health-based violations. PFAS "forever chemicals" were detected in UCMR5 testing (1 compound found).

Water Quality Snapshot: ONAWA MUNICIPAL WATER PLANT

ONAWA MUNICIPAL WATER PLANT is a local-owned community water system that delivers drinking water to 2,906 residents in ONAWA, Iowa (Monona County) through 1,350 service connections. Its water is drawn from groundwater sources. EPA's Safe Drinking Water Information System records 3 total violations for this system , of which 0 (0%) are health-based — meaning a contaminant exceeded an EPA Maximum Contaminant Level or a required treatment technique failed. A further 2 monitoring and reporting violations are on file. The most recent violation on record dates to 1988.

The most frequently cited contaminant at this system is Nitrate, recorded in 2 violations (MR). Under EPA's UCMR5 PFAS monitoring program, 1 PFAS compound was detected in samples collected from this system, with a maximum reported concentration of 60 ppt. PFAS are persistent synthetic chemicals linked to health effects at very low exposure levels.

Across Iowa, EPA tracks 1,795 public water systems serving 3,114,444 people, with 138,271 cumulative violations and 27,946 health-based violations on record. About 95% of systems in the state carry at least one violation, and state-wide the average per system is 77 violations. ONAWA MUNICIPAL WATER PLANT's 3 violations sit below the Iowa average. Statewide, 127 of 152 UCMR5-tested systems have reported PFAS detections (83.6%). All figures above are sourced directly from EPA SDWIS and UCMR5 public data releases and are updated as EPA publishes new reporting cycles.

PFAS Detected

1 PFAS "forever chemicals" detected in testing under EPA's UCMR5 monitoring program.

Population Served
2,906
Total Violations
3
Health-Based Violations
0
Water Source
Groundwater

System Details

System Type
Community
Owner Type
Local
Connections
1,350
County
Monona
School/Daycare
No
MCL Violations
0
Monitoring Violations
2
Treatment Tech Violations
0

Violation History

Contaminant violations recorded by EPA.

Contaminant Category Count Latest
Nitrate MR 2 1988

PFAS Testing Results (UCMR5)

Results from EPA's Fifth Unregulated Contaminant Monitoring Rule. 2 of 60 samples detected PFAS.

Contaminant Date Result MRL Status
PFEESA 9/9/2025 <0.003 µg/L 0.003 µg/L Not Detected
PFUnA 9/9/2025 <0.002 µg/L 0.002 µg/L Not Detected
11Cl-PF3OUdS 9/9/2025 <0.005 µg/L 0.005 µg/L Not Detected
9Cl-PF3ONS 9/9/2025 <0.002 µg/L 0.002 µg/L Not Detected
ADONA 9/9/2025 <0.003 µg/L 0.003 µg/L Not Detected
HFPO-DA 9/9/2025 <0.005 µg/L 0.005 µg/L Not Detected
PFPeS 9/9/2025 <0.004 µg/L 0.004 µg/L Not Detected
6:2 FTS 9/9/2025 <0.005 µg/L 0.005 µg/L Not Detected
8:2 FTS 9/9/2025 <0.005 µg/L 0.005 µg/L Not Detected
PFMPA 9/9/2025 <0.004 µg/L 0.004 µg/L Not Detected
PFHxA 9/9/2025 <0.003 µg/L 0.003 µg/L Not Detected
PFMBA 9/9/2025 <0.003 µg/L 0.003 µg/L Not Detected
PFBA 9/9/2025 <0.005 µg/L 0.005 µg/L Not Detected
PFHpS 9/9/2025 <0.003 µg/L 0.003 µg/L Not Detected
PFTA 9/9/2025 <0.008 µg/L 0.008 µg/L Not Detected
PFTrDA 9/9/2025 <0.007 µg/L 0.007 µg/L Not Detected
NEtFOSAA 9/9/2025 <0.005 µg/L 0.005 µg/L Not Detected
NMeFOSAA 9/9/2025 <0.006 µg/L 0.006 µg/L Not Detected
PFDA 9/9/2025 <0.003 µg/L 0.003 µg/L Not Detected
lithium 9/9/2025 60.0000 µg/L 9 µg/L Detected
PFPeA 9/9/2025 <0.003 µg/L 0.003 µg/L Not Detected
PFHpA 9/9/2025 <0.003 µg/L 0.003 µg/L Not Detected
NFDHA 9/9/2025 <0.02 µg/L 0.02 µg/L Not Detected
4:2 FTS 9/9/2025 <0.003 µg/L 0.003 µg/L Not Detected
PFBS 9/9/2025 <0.003 µg/L 0.003 µg/L Not Detected
PFHxS 9/9/2025 <0.003 µg/L 0.003 µg/L Not Detected
PFNA 9/9/2025 <0.004 µg/L 0.004 µg/L Not Detected
PFDoA 9/9/2025 <0.003 µg/L 0.003 µg/L Not Detected
PFOS 9/9/2025 <0.004 µg/L 0.004 µg/L Not Detected
PFOA 9/9/2025 <0.004 µg/L 0.004 µg/L Not Detected
11Cl-PF3OUdS 3/4/2025 <0.005 µg/L 0.005 µg/L Not Detected
PFUnA 3/4/2025 <0.002 µg/L 0.002 µg/L Not Detected
PFHxA 3/4/2025 <0.003 µg/L 0.003 µg/L Not Detected
9Cl-PF3ONS 3/4/2025 <0.002 µg/L 0.002 µg/L Not Detected
PFTrDA 3/4/2025 <0.007 µg/L 0.007 µg/L Not Detected
PFHpS 3/4/2025 <0.003 µg/L 0.003 µg/L Not Detected
ADONA 3/4/2025 <0.003 µg/L 0.003 µg/L Not Detected
PFTA 3/4/2025 <0.008 µg/L 0.008 µg/L Not Detected
PFPeA 3/4/2025 <0.003 µg/L 0.003 µg/L Not Detected
PFOA 3/4/2025 <0.004 µg/L 0.004 µg/L Not Detected
PFDoA 3/4/2025 <0.003 µg/L 0.003 µg/L Not Detected
HFPO-DA 3/4/2025 <0.005 µg/L 0.005 µg/L Not Detected
PFBA 3/4/2025 <0.005 µg/L 0.005 µg/L Not Detected
6:2 FTS 3/4/2025 <0.005 µg/L 0.005 µg/L Not Detected
4:2 FTS 3/4/2025 <0.003 µg/L 0.003 µg/L Not Detected
PFPeS 3/4/2025 <0.004 µg/L 0.004 µg/L Not Detected
PFMPA 3/4/2025 <0.004 µg/L 0.004 µg/L Not Detected
PFBS 3/4/2025 <0.003 µg/L 0.003 µg/L Not Detected
PFHpA 3/4/2025 <0.003 µg/L 0.003 µg/L Not Detected
PFHxS 3/4/2025 <0.003 µg/L 0.003 µg/L 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 ONAWA MUNICIPAL WATER PLANT.

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 IA6739095 on SDWIS

Source: EPA SDWIS Federal Reports Search

State Regulator

Iowa Drinking Water Authority

Iowa'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 IA 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
1988 Nitrate MR 2 SDWIS / IA6739095 / 1040

How ONAWA MUNICIPAL WATER PLANT Compares

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

Metric ONAWA MUNICIPAL WATER PLANT Iowa avg Federal benchmark
Total violations 3 77 SDWA compliance — any non-zero count is a recorded breach
Health-based violations 0 15.6 Indicates a contaminant exceeded a federal MCL
PFAS detection 1 compound 83.6% EPA final rule (2024): PFOA/PFOS MCL = 4.0 ppt
Population served 2,906 1,735 Sizing context for compliance burden

Sources: EPA SDWIS and EPA National Primary Drinking Water Regulations (40 CFR Part 141). State averages computed across 1,795 regulated public water systems in Iowa.

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
Nitrate (as N) 10 mg/L Acute health risk for infants

Frequently Asked Questions

Is ONAWA MUNICIPAL WATER PLANT water safe to drink? ▼
ONAWA MUNICIPAL WATER PLANT (PWS ID: IA6739095) has 3 recorded violations in the EPA SDWIS database. PFAS contamination has been detected in UCMR5 testing, with 1 PFAS compound found. This system serves 2,906 people using Groundwater sources.
How many people does ONAWA MUNICIPAL WATER PLANT serve? ▼
ONAWA MUNICIPAL WATER PLANT serves 2,906 people in ONAWA, Iowa. It is a Local-owned system using Groundwater water sources with 1,350 service connections.
What type of violations does ONAWA MUNICIPAL WATER PLANT have? ▼
ONAWA MUNICIPAL WATER PLANT has 3 total violations: 0 health-based violations (MCL exceedances or treatment failures), 2 monitoring/reporting violations, and 0 treatment technique violations. Health-based violations indicate contaminant levels exceeded EPA safe limits.
Has PFAS been detected in ONAWA MUNICIPAL WATER PLANT water? ▼
Yes. UCMR5 testing detected 1 PFAS compound in ONAWA MUNICIPAL WATER PLANT's water supply: lithium. PFAS are persistent "forever chemicals" that do not break down in the environment.
What water source does ONAWA MUNICIPAL WATER PLANT use? ▼
ONAWA MUNICIPAL WATER PLANT 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.

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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.

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

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Data sourced from $official public datasets. See our methodology for details. Retrieved and formatted by Kiznis Studio Editorial