States › Oklahoma

Oklahoma Tap Water Quality 2026

EPA drinking water data for 798 cities across Oklahoma — covering lead levels, violation history, and compliance status.

Systems tracked: 566 Cities covered: 798 Updated: 2026 Q2
B

Oklahoma earns a B for overall water quality

798 communities across 77 counties and 566 water systems. 98.6% have no open violations.

Median lead where detected: 2.00 ppb
42.9% of systems report lead as not detected — a state filing convention, not a water quality measure
PFAS tested at 25.1% of communities; 10 above the federal limit
Lead reported for 100.0% of communities
98.6% of communities have no open violations
Water Systems
566
Active community systems
Median Lead Level
2 ppb
13% of EPA action level
Fully Compliant
98.6%
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 Oklahoma

✓ Cleanest Water
Oklahoma City
Oklahoma County
0.0 ppb A
Tulsa
Tulsa County
1.2 ppb A
Edmond
Oklahoma County
0.8 ppb A
Lawton
Comanche County
2.0 ppb A
Midwest City
Oklahoma County
1.2 ppb A
Owasso
Tulsa County
0.0 ppb A
⚠ Needs Attention
East Duke
Jackson County
0.0 ppb D
Peoria
Ottawa County
0.0 ppb D
Earlsboro
Pottawatomie County
4.0 ppb D
Johnson
Pottawatomie County
4.0 ppb D
Leonard
Tulsa County
1.0 ppb D
Fair Oaks
Wagoner County
1.0 ppb D

Water Quality by County

77 of 77
Sort:
CountySystemsLead LevelViolationsGrade
Sequoyah County 30 2.8 ppb 0 B
Adair County 27 4.1 ppb 0 B
Cherokee County 27 1.0 ppb 0 B
Mayes County 26 2.0 ppb 0 B
Pittsburg County 23 2.9 ppb 0 B
Delaware County 23 1.8 ppb 0 B
Le Flore County 20 1.1 ppb 0 B
Oklahoma County 20 1.6 ppb 0 B
Bryan County 19 0.6 ppb 0 B
Osage County 19 2.3 ppb 0 B

About Oklahoma Drinking Water

Oklahoma is served by 566 community water systems covering 798 communities across 77 counties. 98.6% have no open violation on record.

Lead was detected in 456 communities, with a median of 2.00 ppb — 13% of the federal action level. A further 342 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 25.1% of communities here, and 10 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 Oklahoma tap water safe to drink? ▼
98.6% of communities have no open violation on record. 10 have PFAS above the federal limit set in 2024, which is the main open concern.
Does Oklahoma have a lead problem? ▼
5 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 342 communities report no detection at all.
How complete is the data for Oklahoma? ▼
Lead results are reported for 100.0% of communities and PFAS for 25.1%. Where a figure is missing it is shown as not reported rather than assumed safe.
How does Oklahoma 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.