WaterVerge

Is Marion, OH Tap Water Safe to Drink?

Graded B- — but Copper, Strontium and 2 more were detected above EPA limits. Here's what's in the water and how to remove it. What to do next ↓

67K residents served 3 water systems PWSID: OH5100414
Overall Score
74.8 / 100
Violations
17 active
Last Updated
May 2026
Source
Surface water
#363 of 511 in Ohio Top 62% nationally
Private
High data confidence
Reviewed by WaterVerge Editorial Team · Last updated May 2026
B-GRADE
Water Quality Grade
74.8/100
waterverge.com
B- 74.8/100

Marion, OH — Water Quality Report

Marion's drinking water received a grade of B- (74.8 out of 100), indicating fair water quality. The city's 3 water systems serve approximately 67,152 residents using surface water.

Lead levels were measured at 0.0 ppb (90th percentile), well within EPA limits. UCMR 5 testing detected 1 PFAS compound in the water supply.

The system has 52 violations on record, including 9 health-based violations. 17 remain unresolved.

Data last updated: May 2026 · Source: EPA SDWIS, UCMR 5
Analysis

What to know about Marion's water

Marion ranks #363 out of 511 cities in Ohio for water quality, placing it below average in the state.

The city draws from surface water sources, which are more susceptible to seasonal runoff and agricultural contamination, requiring extensive multi-barrier treatment including coagulation, filtration, and disinfection.

PFAS compounds were detected in testing, though levels remain within current EPA limits. Residents seeking extra precaution may consider an activated carbon or reverse osmosis filter.

Hexavalent chromium (chromium-6) was detected at 0.28 µg/L in UCMR 3 testing. While below California's 10 µg/L limit and with no federal MCL set, residents sensitive to this contaminant may consider reverse osmosis filtration.

Quality Breakdown

Water quality score

See methodology →
74.8 out of 100 Grade B-
A: 90-100
B: 74-89
C: 60-73
F: <50
How is this calculated?
Violations
35.2/45
B
Historical violation record including health-based and monitoring violations.
Lead & Copper
16/20
B
Lead at 0.0 ppb (90th percentile).
Contaminants
14.6/20
C
1 PFAS compound detected.
Compliance
5/10
D
Monitoring and reporting compliance with EPA regulations.
Source Risk
4/5
B
Water source: Surface water.
Water Safety

Is Marion, OH water safe to drink?

Concerns Identified

Marion's drinking water has significant quality concerns based on EPA testing data. With a grade of B- (74.8/100), the system has issues across multiple categories. A water filter is recommended for all residents. The city's 3 water systems serve approximately 67,152 residents using surface water (rivers, lakes, or reservoirs).

17
Active Violations
0.0 ppb
Lead (90th %ile)
1 compound
PFAS Detected
2 events
Disaster History

Recent water quality updates for Marion

A timeline of significant water quality events, violations, and data updates.

PFAS
1 PFAS "forever chemical" compound detected

Detected at levels within current EPA limits. PFAS persist indefinitely in the environment.

Update
Water quality data updated

Latest EPA compliance and testing data incorporated into Marion's water quality assessment. Grade: B- (74.8/100).

Violation
1 drinking water violation recorded

Contaminants: Consumer Confidence Rule.

Violation
1 drinking water violation recorded

Contaminants: Consumer Confidence Rule.

Violation
1 drinking water violation recorded

Contaminants: Consumer Confidence Rule.

Disaster
HURRICANE KATRINA EVACUATION

Federal disaster declaration (FEMA DR-3250). Hurricane event — may have impacted local water infrastructure.

Key contaminant findings

Based on the most recent EPA sampling data for Marion's water supply.

Lead Within Limits
Detected: 0.0 ppb Limit: 15 ppb (EPA Action Level)

Well within EPA limits.

Copper Exceeds Limit
Detected: 23.00 mg/L Limit: 1.3 mg/L (EPA Action Level)

Exceeds EPA action level. Copper can leach from household plumbing — flush taps for 30 seconds before drinking.

PFAS (1 compound) Elevated
Detected: Highest: lithium at 19.4000 µg/L Limit: 0.004 µg/L (EPA MCL)

Detected but within current EPA limits. PFAS do not break down in the environment and can accumulate in the body over time. An activated carbon filter can reduce exposure.

Violation history

Marion's water system has 52 total violations on record, including 9 health-based violations. 17 remain unresolved. 3 violations were issued in the last 5 years.

OtherMONMRTTMCL
Most recent violations:
Dec 2022 Consumer Confidence Rule Open
Jul 2022 Consumer Confidence Rule Open
Jan 2022 Consumer Confidence Rule Open
Oct 2020 Consumer Confidence Rule Open
Jan 2020 Consumer Confidence Rule Open

Flood & environmental risk

Marion County has experienced 2 federally declared disasters since 1987. Flooding and severe storms can overwhelm water treatment plants, cause sewage overflows, and introduce agricultural runoff, bacteria, and sediment into drinking water supplies. Local water sources include Olentangy River At Claridon.

HURRICANE KATRINA EVACUATION
Hurricane FEMA DR-3250
SEVERE STORMS & FLOODING
Flood FEMA DR-796

Where does Marion's water come from?

Marion's drinking water comes from surface water (rivers, lakes, or reservoirs), supplied by 3 water systems serving approximately 67,152 people. Surface water sources are more susceptible to contamination from runoff, industrial discharge, and algal blooms, requiring extensive treatment. Nearby water bodies include Olentangy River At Claridon (river).

What Marion residents can do

Install a water filter

Recommended: Activated carbon or reverse osmosis filter. This addresses the specific contaminants found in Marion's water.

Request your utility's CCR

Your water utility is required to publish an annual Consumer Confidence Report (CCR) with detailed testing results. Ask for the latest copy or check your utility's website.

Data: EPA SDWIS, UCMR 5 (PFAS), FEMA, NOAA. Last updated May 2026.

Contaminant Alerts

Top contaminants to know

View all ↓
Lead (90th percentile)
Inorganic / Heavy Metal
Safe
0.0 ppb
EPA Action Level: 15 ppb · 0% of limit
Safe Level
Copper (90th percentile)
Inorganic
Over Limit
23.00 mg/L
EPA Action Level: 1.3 mg/L · +20% over limit
Exceeds Limit
lithium
PFAS / Forever Chemical
Near MCL
19.4000 µg/L
EPA MCL: 0.004 µg/L · +20% over limit
Detected
HAA5 (Disinfection Byproducts)
Disinfection Byproduct
Safe
27.5 µg/L
EPA MCL: 60 µg/L · 46% of limit
Within LimitUCMR 4 DataHAA6Br: 7.2 µg/LHAA9: 34.3 µg/L
Chromium-6 (Hexavalent Chromium)
Inorganic
Detected
0.28 µg/L
CA MCL (no federal MCL): 10 µg/L · 3% of limit
DetectedUCMR 3 Data
Strontium
Inorganic
Over HRL
11000.0 µg/L
EPA Health Ref Level: 1,500 µg/L · +20% over limit
Over HRLUCMR 3 Data
1,4-Dioxane
Organic
Over HA
1.50 µg/L
EPA Health Advisory: 0.35 µg/L · +20% over limit
Over Health AdvisoryUCMR 3 Data
Manganese
Inorganic
Detected
6.9 µg/L
EPA Secondary MCL: 50 µg/L · 14% of limit
DetectedUCMR 4 Data
Vanadium
Inorganic
Detected
0.91 µg/L
EPA Short-term HA: 21 µg/L · 4% of limit
DetectedUCMR 3 Data
Chlorate
Disinfection Byproduct
Over HA
270.0 µg/L
EPA Lifetime HA: 210 µg/L · +20% over limit
Over Health AdvisoryUCMR 3 Data
Molybdenum
Inorganic
Detected
16.00 µg/L
EPA Lifetime HA: 40 µg/L · 40% of limit
DetectedUCMR 3 Data
Lithium
Inorganic
Detected
19.4 µg/L
State screening level: 60 µg/L · 32% of limit
DetectedNo federal MCLUCMR 5 Data (2023–2025)
PFAS Testing

Forever chemicals overview

National PFAS report →
30
Compounds tested
1
Detected
0
Exceed EPA MCL
Compliance Record

Violation summary

52
Total violations
9
Health-based
17
Active / unresolved
Dec 2022
Most recent violation
Compliance Record

Violations & advisories

52 Total
17 Active
9 Health-based
35 Resolved
4 SNC
Violations by category
Synthetic Organic Chemicals
16
Consumer Confidence Rule
10
Stage 2 Disinfectants and Disinfection Byproducts Rule
7
Surface Water Treatment Rule
6
Stage 1 Disinfectants and Disinfection Byproducts Rule
2
Dec 2022 Active
Consumer Confidence Rule
Other Violation 0
Jul 2022 Active
Consumer Confidence Rule
Other Violation 0
Jan 2022 Active
Consumer Confidence Rule
Other Violation 0
Oct 2020 Active
Consumer Confidence Rule
Other Violation 0
Jan 2020 Active
Consumer Confidence Rule
Other Violation 0
Dec 2019 Active
Consumer Confidence Rule
Other Violation 0
Nov 2019 Active
Public Notice
Other Violation 0
Sep 2018 Active
Consumer Confidence Rule
Other Violation 0
Oct 2017 Active
Groundwater Rule
Treatment Technique
Health-Based Health 0
Jan 2010 Active
Stage 2 Disinfectants and Disinfection Byproducts Rule
Monitoring & Reporting
Monitoring & Reporting 0
Dec 2009 Active
Lead and Copper Rule
Monitoring & Reporting
Monitoring & Reporting 0
Jul 2004 Active
Consumer Confidence Rule
Other Violation 0
Jul 2003 Active
Consumer Confidence Rule
Other Violation 0
Jul 2002 Active
Consumer Confidence Rule
Other Violation 0
Active
Compliance Violation
Monitoring 0
Active
Compliance Violation
Monitoring 0
Active
Compliance Violation
Monitoring 0
Nov 2019 Resolved
Revised Total Coliform Rule
Monitoring
Monitoring Resolved Nov 2019
Jan 2019 Resolved
TTHM
Monitoring & Reporting
SNC Monitoring & Reporting Resolved Dec 2019
Jan 2019 Resolved
Total Haloacetic Acids (HAA5)
Monitoring & Reporting
SNC Monitoring & Reporting Resolved Dec 2019
Showing 20 of 52 violations
Industrial pollution

Top industrial polluters within 10 miles of Marion

Industrial polluters nearby

Reported releases to surface water by facilities near Marion, ranked by pounds discharged annually.

Total reported releases to surface water: 8 lbs

FacilityTop chemicalTo surface water (lbs/yr)Distance
HILDRETH MANUFACTURING LLC
Primary Metals · NA
MARION, OH43302
Copper82.2 mi
NUCOR STEEL MARION INC
Primary Metals · NUCOR CORP
MARION, OH43302
Zinc compounds02.0 mi
ARCELORMITTAL TUBULAR PRODUCTS USA LLC
Primary Metals · ARCELORMITTAL NORTH AMERICA HOLDINGS LLC
MARION, OH43302
1.2 mi
OHIO GALVANIZING CORP
Fabricated Metals · NA
MARION, OH43302
0.9 mi
NACHURS ALPINE SOLUTIONS
Chemicals · WILBUR-ELLIS CO LLC
MARION, OH43302
0.8 mi

Source: EPA Toxic Release Inventory (TRI) 2023

Site context

Superfund sites within 10 miles of Marion

Superfund sites nearby

Federally tracked hazardous-waste sites on the EPA National Priorities List. Proximity does not necessarily indicate tap-water contamination — the connection depends on hydrology and treatment.

Source: EPA Superfund National Priorities List

Environmental Risk

Flood & disaster history

2
Declared disasters
Sep 2005
Most recent
Hurricane
Most common type

Marion County has experienced 2 federally declared disasters since 1987. Flooding and severe weather can compromise water treatment infrastructure and introduce contaminants into drinking water supplies.

Sep 2005
HURRICANE KATRINA EVACUATION
Hurricane FEMA #3250
Jul 1987
SEVERE STORMS & FLOODING
Flood FEMA #796

Recommended water filters

Based on contaminants detected in Marion's water supply, we recommend the following filter types.

🧪
For PFAS
Reverse Osmosis or Activated Carbon Block
1 PFAS compound detected
🔧
For Copper
Reverse Osmosis or KDF Filter
Copper exceeds the EPA action level of 1.3 mg/L

Full contaminants report

Contaminant Detected Level EPA Limit Unit Category Status
Lead (90th percentile) 0.0 15 ppb Inorganic Safe
Copper (90th percentile) 23.00 1.3 mg/L Inorganic Over Limit
11Cl-PF3OUdS ND HI µg/L PFAS Not Detected
4:2 FTS ND HI µg/L PFAS Not Detected
6:2 FTS ND HI µg/L PFAS Not Detected
8:2 FTS ND HI µg/L PFAS Not Detected
9Cl-PF3ONS ND HI µg/L PFAS Not Detected
ADONA ND HI µg/L PFAS Not Detected
HFPO-DA ND 0.01 µg/L PFAS Not Detected
lithium 19.400 HI µg/L PFAS Detected
NEtFOSAA ND HI µg/L PFAS Not Detected
NFDHA ND HI µg/L PFAS Not Detected
NMeFOSAA ND HI µg/L PFAS Not Detected
PFBA ND HI µg/L PFAS Not Detected
PFBS ND HI µg/L PFAS Not Detected
PFDA ND HI µg/L PFAS Not Detected
PFDoA ND HI µg/L PFAS Not Detected
PFEESA ND HI µg/L PFAS Not Detected
PFHpA ND HI µg/L PFAS Not Detected
PFHpS ND HI µg/L PFAS Not Detected
PFHxA ND HI µg/L PFAS Not Detected
PFHxS ND HI µg/L PFAS Not Detected
PFMBA ND HI µg/L PFAS Not Detected
PFMPA ND HI µg/L PFAS Not Detected
PFNA ND HI µg/L PFAS Not Detected
PFOA ND 0.004 µg/L PFAS Not Detected
PFOS ND 0.004 µg/L PFAS Not Detected
PFPeA ND HI µg/L PFAS Not Detected
PFPeS ND HI µg/L PFAS Not Detected
PFTA ND HI µg/L PFAS Not Detected
PFTrDA ND HI µg/L PFAS Not Detected
PFUnA ND HI µg/L PFAS Not Detected
Data source: EPA SDWIS, UCMR 5, local utility CCR.

Lead level trend (90th percentile)

EPA action level: 15 ppb
Lead has decreased by 9.6 ppb from 1992 (15.0 ppb) to 2025 (5.4 ppb).

Copper level (90th percentile)

Latest reading: 23.000 mg/L (2004)

EPA action level: 1.3 mg/L

Infrastructure

Water source & infrastructure

Primary Source
Surface Water
Operator
Private
Population Served
67,152
Water Systems
3
Source breakdown
Surface Water
2
Groundwater
1
Water Source

Where Marion's water comes from

Surface Water

Marion's drinking water comes primarily from surface water sources such as rivers, lakes, or reservoirs.

Surface water systems require multi-stage treatment including coagulation, sedimentation, filtration, and disinfection to meet EPA Safe Drinking Water Act standards.

These sources can be impacted by seasonal changes, stormwater runoff, upstream agriculture, and industrial discharge.

The system is operated by private ownership and serves approximately 67,152 people through 3 water systems.

Local Hydrology

Water bodies near Marion

Marion is located near 1 notable water body. As a surface water system, these water bodies may directly influence the city's drinking water supply.

Olentangy River At Claridon
river
Infrastructure

Water systems serving Marion

System Name PWSID Population Source
AQUA OHIO - MARION OH5100414 46,317 SW
AQUA OHIO - TIFFIN OH7400614 20,035 SW
AQUA OHIO - LA RUE VILLAGE OH5100312 800 GW
Regional Comparison

How Marion compares

Full Ohio rankings →

Marion's score of 74.8/100 is above the average of 58/100 among major Ohio cities. It outscores 6 of 10 nearby cities.

Marion (this city)
74.8
Columbus
35.5
Cleveland
85.5
Cincinnati
36.8
Toledo
78
Kent
38.2
Ohio avg
58
City Profile

About Marion, OH

Wikipedia →

Marion is a city in Marion County, Ohio, United States, and its county seat. It is located in north-central Ohio, approximately 50 miles (80 km) north of Columbus. The population was 35,999 at the 2020 census, down slightly from 36,837 at the 2010 census. It is the largest city in Marion County and the principal city of the Marion micropolitan area. It is also part of the larger Columbus–Marion–Zanesville, OH Combined Statistical Area.

Economic Profile
$44,879
Median Income
$98,423
Median Home Value
$842/mo
Median Rent
8.7%
Unemployment
Community
37.7
Median Age
1,070
People / sq mi
10.1%
College Educated
55.1%
Homeownership
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Frequently asked questions

Is Marion, OH tap water safe to drink?

Marion's water quality earned a grade of B- (74.8/100). Some concerns have been identified. Consider a water filter for an extra layer of protection. The city ranks #363 out of 511 cities tested in Ohio.

What contaminants are in Marion's water?

Lead was measured at 0.0 ppb (90th percentile). 1 PFAS compound was detected. 52 violations are on record.

How is Marion's water quality grade calculated?

The grade is based on four factors: violation history (40%), lead and copper levels (25%), PFAS contamination (25%), and regulatory compliance (10%). The score is also adjusted based on how complete the available data is. See our methodology page for full details.

Do I need a water filter in Marion?

PFAS compounds have been detected. A filter with activated carbon can help reduce exposure.

Where does Marion's water come from?

Marion's water is sourced from Surface water. The city has 3 water systems serving approximately 67,152 residents.

What health violations has Marion's water system had?

Marion has 9 health-based violations on record. The most recent violation was recorded in December 2022. Health-based violations mean the water exceeded EPA maximum contaminant levels (MCLs) for a regulated substance. 17 violations remain unresolved.

How does Marion's water compare to other cities?

Marion ranks #363 out of 511 cities in Ohio (better than 29% of state cities) and #9731 out of 15744 cities nationally (38th percentile). The grade of B- reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.