States › Ohio

Ohio Tap Water Quality 2026

EPA drinking water data for 1,048 cities across Ohio — covering lead levels, violation history, and compliance status.

Systems tracked: 654 Cities covered: 1,048 Updated: 2026 Q2
B

Ohio earns a B for overall water quality

1048 communities across 88 counties and 654 water systems. 97.9% have no open violations.

Median lead where detected: 2.00 ppb
43.1% of systems report lead as not detected — a state filing convention, not a water quality measure
PFAS tested at 59.0% of communities; 120 above the federal limit
Lead reported for 100.0% of communities
97.9% of communities have no open violations
Water Systems
654
Active community systems
Median Lead Level
2 ppb
13% of EPA action level
Fully Compliant
97.9%
of systems — no active violations
How we grade states Grades are based on actual EPA enforcement data — MCL violations and lead levels measured against the 15 ppb federal action level. We do not use MCLG-based detections, which are aspirational zero-tolerance goals that would make nearly every state look dangerous. Read our full methodology →

Best & Worst Cities in Ohio

✓ Cleanest Water
Brady Lake
Portage County
4.0 ppb B
Medway
Clark County
2.5 ppb B
Rendville
Perry County
0.0 ppb A
Holiday Valley
Clark County
0.0 ppb A
Hamilton
Butler County
2.0 ppb A
Beavercreek
Greene County
0.0 ppb A
⚠ Needs Attention
Rock Creek
Ashtabula County
0.6 ppb F
McDonald
Trumbull County
0.0 ppb F
Hilltop
Trumbull County
0.0 ppb F
Devola
Washington County
6.7 ppb D
The Village of Indian Hill
Hamilton County
1.7 ppb D
Madeira
Hamilton County
1.7 ppb D

Water Quality by County

88 of 88
Sort:
CountySystemsLead LevelViolationsGrade
Hamilton County 86 2.1 ppb 0 C
Cuyahoga County 57 1.7 ppb 0 B
Franklin County 29 1.2 ppb 0 B
Stark County 27 2.8 ppb 0 B
Summit County 27 2.7 ppb 0 B
Trumbull County 26 3.7 ppb 0 B
Montgomery County 22 2.0 ppb 0 B
Licking County 20 1.6 ppb 0 A
Clermont County 20 2.1 ppb 0 C
Belmont County 19 4.8 ppb 0 B

About Ohio Drinking Water

Ohio is served by 654 community water systems covering 1048 communities across 88 counties. 97.9% have no open violation on record.

Lead was detected in 596 communities, with a median of 2.00 ppb — 13% of the federal action level. A further 452 reported none detected. That share is a state reporting convention rather than a measure of water quality, so it is stated separately rather than averaged in.

PFAS has been tested at 59.0% of communities here, and 120 are above the limits EPA set in 2024. Coverage matters: states that test more find more, so this figure is not comparable with a state that has tested less.

Frequently Asked Questions

Is Ohio tap water safe to drink? ▼
97.9% of communities have no open violation on record. 120 have PFAS above the federal limit set in 2024, which is the main open concern.
Does Ohio have a lead problem? ▼
2 water systems report a 90th-percentile lead result at or above the 15 ppb action level. The action level is a treatment trigger, not a legal maximum, and 452 communities report no detection at all.
How complete is the data for Ohio? ▼
Lead results are reported for 100.0% of communities and PFAS for 59.0%. Where a figure is missing it is shown as not reported rather than assumed safe.
How does Ohio compare with other states? ▼
We do not rank states against each other. Lead reporting completeness ranges from under 20% to 100% depending on the state, so a national ranking would compare filing practice rather than water quality.