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ONTARIO CITY

PWS ID: OH7003512 · ONTARIO, Ohio 44906

ONTARIO CITY serves 6,656 people in ONTARIO, Ohio using Groundwater water sources. It has 67 recorded EPA violations, including 0 health-based violations. PFAS "forever chemicals" were detected in UCMR5 testing (1 compound found).

Water Quality Snapshot: ONTARIO CITY

ONTARIO CITY is a local-owned community water system that delivers drinking water to 6,656 residents in ONTARIO, Ohio (Richland County) through 2,684 service connections. Its water is drawn from groundwater sources. EPA's Safe Drinking Water Information System records 67 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 64 monitoring and reporting violations are on file. The most recent violation on record dates to 2018.

The most frequently cited contaminant at this system is Asbestos, recorded in 4 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 14.3 ppt. PFAS are persistent synthetic chemicals linked to health effects at very low exposure levels.

Across Ohio, EPA tracks 4,181 public water systems serving 11,085,226 people, with 288,388 cumulative violations and 52,412 health-based violations on record. About 90% of systems in the state carry at least one violation, and state-wide the average per system is 69 violations. ONTARIO CITY's 67 violations sit below the Ohio average. Statewide, 204 of 346 UCMR5-tested systems have reported PFAS detections (59%). 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
6,656
Total Violations
67
Health-Based Violations
0
Water Source
Groundwater

System Details

System Type
Community
Owner Type
Local
Connections
2,684
County
Richland
School/Daycare
No
MCL Violations
0
Monitoring Violations
64
Treatment Tech Violations
0

Violation History

Contaminant violations recorded by EPA.

Contaminant Category Count Latest
Asbestos MR 4 1995
Arsenic MR 4 1995
Barium MR 4 1995
Cadmium MR 4 1995
Chromium MR 4 1995
Fluoride MR 4 1995
Mercury MR 4 1995
Nickel MR 4 1995
Selenium MR 4 1995
Thallium, Total MR 4 1995
Coliform (TCR) MR 4 1998
Nitrate MR 4 1999
Beryllium, Total MR 4 1995
CYANIDE MR 4 1995
Antimony, Total MR 4 1995
Gross Alpha, Excl. Radon and U MR 4 1995
Consumer Confidence Rule Other 3 2018

PFAS Testing Results (UCMR5)

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

Contaminant Date Result MRL Status
PFHpA 5/9/2023 <0.003 µg/L 0.003 µg/L Not Detected
PFHxS 5/9/2023 <0.003 µg/L 0.003 µg/L Not Detected
9Cl-PF3ONS 5/9/2023 <0.002 µg/L 0.002 µg/L Not Detected
11Cl-PF3OUdS 5/9/2023 <0.005 µg/L 0.005 µg/L Not Detected
PFUnA 5/9/2023 <0.002 µg/L 0.002 µg/L Not Detected
PFHxA 5/9/2023 <0.003 µg/L 0.003 µg/L Not Detected
PFDoA 5/9/2023 <0.003 µg/L 0.003 µg/L Not Detected
HFPO-DA 5/9/2023 <0.005 µg/L 0.005 µg/L Not Detected
PFBA 5/9/2023 <0.005 µg/L 0.005 µg/L Not Detected
6:2 FTS 5/9/2023 <0.005 µg/L 0.005 µg/L Not Detected
4:2 FTS 5/9/2023 <0.003 µg/L 0.003 µg/L Not Detected
PFNA 5/9/2023 <0.004 µg/L 0.004 µg/L Not Detected
8:2 FTS 5/9/2023 <0.005 µg/L 0.005 µg/L Not Detected
PFBS 5/9/2023 <0.003 µg/L 0.003 µg/L Not Detected
PFOS 5/9/2023 <0.004 µg/L 0.004 µg/L Not Detected
PFOA 5/9/2023 <0.004 µg/L 0.004 µg/L Not Detected
PFDA 5/9/2023 <0.003 µg/L 0.003 µg/L Not Detected
PFMPA 5/9/2023 <0.004 µg/L 0.004 µg/L Not Detected
PFPeA 5/9/2023 <0.003 µg/L 0.003 µg/L Not Detected
PFMBA 5/9/2023 <0.003 µg/L 0.003 µg/L Not Detected
PFEESA 5/9/2023 <0.003 µg/L 0.003 µg/L Not Detected
NFDHA 5/9/2023 <0.02 µg/L 0.02 µg/L Not Detected
PFPeS 5/9/2023 <0.004 µg/L 0.004 µg/L Not Detected
PFHpS 5/9/2023 <0.003 µg/L 0.003 µg/L Not Detected
NMeFOSAA 5/9/2023 <0.006 µg/L 0.006 µg/L Not Detected
NEtFOSAA 5/9/2023 <0.005 µg/L 0.005 µg/L Not Detected
PFTrDA 5/9/2023 <0.007 µg/L 0.007 µg/L Not Detected
PFTA 5/9/2023 <0.008 µg/L 0.008 µg/L Not Detected
lithium 5/9/2023 14.3000 µg/L 9 µg/L Detected
ADONA 5/9/2023 <0.003 µg/L 0.003 µg/L Not Detected
6:2 FTS 12/18/2023 <0.005 µg/L 0.005 µg/L Not Detected
NMeFOSAA 12/18/2023 <0.006 µg/L 0.006 µg/L Not Detected
PFUnA 12/18/2023 <0.002 µg/L 0.002 µg/L Not Detected
ADONA 12/18/2023 <0.003 µg/L 0.003 µg/L Not Detected
PFBS 12/18/2023 <0.003 µg/L 0.003 µg/L Not Detected
PFHpA 12/18/2023 <0.003 µg/L 0.003 µg/L Not Detected
PFHxS 12/18/2023 <0.003 µg/L 0.003 µg/L Not Detected
PFOA 12/18/2023 <0.004 µg/L 0.004 µg/L Not Detected
PFOS 12/18/2023 <0.004 µg/L 0.004 µg/L Not Detected
NEtFOSAA 12/18/2023 <0.005 µg/L 0.005 µg/L Not Detected
PFTrDA 12/18/2023 <0.007 µg/L 0.007 µg/L Not Detected
PFTA 12/18/2023 <0.008 µg/L 0.008 µg/L Not Detected
PFHxA 12/18/2023 <0.003 µg/L 0.003 µg/L Not Detected
PFPeA 12/18/2023 <0.003 µg/L 0.003 µg/L Not Detected
HFPO-DA 12/18/2023 <0.005 µg/L 0.005 µg/L Not Detected
PFNA 12/18/2023 <0.004 µg/L 0.004 µg/L Not Detected
PFMPA 12/18/2023 <0.004 µg/L 0.004 µg/L Not Detected
PFDoA 12/18/2023 <0.003 µg/L 0.003 µg/L Not Detected
9Cl-PF3ONS 12/18/2023 <0.002 µg/L 0.002 µg/L Not Detected
PFBA 12/18/2023 <0.005 µg/L 0.005 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 ONTARIO CITY.

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 OH7003512 on SDWIS

Source: EPA SDWIS Federal Reports Search

State Regulator

Ohio Drinking Water Authority

Ohio EPA — Division of Drinking and Ground Waters is the primacy agency that licenses and inspects ONTARIO CITY under EPA-delegated authority.

Open OH regulator portal

Source: Ohio EPA — Division of Drinking and Ground Waters

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
2018 Consumer Confidence Rule Other 3 SDWIS / OH7003512 / 7000
1999 Nitrate MR 4 SDWIS / OH7003512 / 1040
1998 Coliform (TCR) MR 4 SDWIS / OH7003512 / 3100
1995 Asbestos MR 4 SDWIS / OH7003512 / 1094
1995 Arsenic MR 4 SDWIS / OH7003512 / 1005
1995 Barium MR 4 SDWIS / OH7003512 / 1010
1995 Cadmium MR 4 SDWIS / OH7003512 / 1015
1995 Chromium MR 4 SDWIS / OH7003512 / 1020
1995 Fluoride MR 4 SDWIS / OH7003512 / 1025
1995 Mercury MR 4 SDWIS / OH7003512 / 1035
1995 Nickel MR 4 SDWIS / OH7003512 / 1036
1995 Selenium MR 4 SDWIS / OH7003512 / 1045
1995 Thallium, Total MR 4 SDWIS / OH7003512 / 1085
1995 Beryllium, Total MR 4 SDWIS / OH7003512 / 1075
1995 CYANIDE MR 4 SDWIS / OH7003512 / 1024

How ONTARIO CITY Compares

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

Metric ONTARIO CITY Ohio avg Federal benchmark
Total violations 67 69 SDWA compliance — any non-zero count is a recorded breach
Health-based violations 0 12.5 Indicates a contaminant exceeded a federal MCL
PFAS detection 1 compound 59% EPA final rule (2024): PFOA/PFOS MCL = 4.0 ppt
Population served 6,656 2,651 Sizing context for compliance burden

Sources: EPA SDWIS and EPA National Primary Drinking Water Regulations (40 CFR Part 141). State averages computed across 4,181 regulated public water systems in Ohio.

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 ONTARIO CITY water safe to drink? ▼
ONTARIO CITY (PWS ID: OH7003512) has 67 recorded violations in the EPA SDWIS database. PFAS contamination has been detected in UCMR5 testing, with 1 PFAS compound found. This system serves 6,656 people using Groundwater sources.
How many people does ONTARIO CITY serve? ▼
ONTARIO CITY serves 6,656 people in ONTARIO, Ohio. It is a Local-owned system using Groundwater water sources with 2,684 service connections.
What type of violations does ONTARIO CITY have? ▼
ONTARIO CITY has 67 total violations: 0 health-based violations (MCL exceedances or treatment failures), 64 monitoring/reporting violations, and 0 treatment technique violations. Health-based violations indicate contaminant levels exceeded EPA safe limits.
Has PFAS been detected in ONTARIO CITY water? ▼
Yes. UCMR5 testing detected 1 PFAS compound in ONTARIO CITY's water supply: lithium. PFAS are persistent "forever chemicals" that do not break down in the environment.
What water source does ONTARIO CITY use? ▼
ONTARIO CITY 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