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Hawaii Tap Water Quality 2026

EPA drinking water data for 141 cities across Hawaii — covering lead levels, violation history, and compliance status.

Systems tracked: 55 Cities covered: 141 Updated: 2026 Q2
A

Hawaii earns an A for overall water quality

141 communities across 4 counties and 55 water systems. 100.0% have no open violations.

Median lead where detected: 0.94 ppb
87.2% of systems report lead as not detected — a state filing convention, not a water quality measure
PFAS tested at 78.0% of communities; 0 above the federal limit
Lead reported for 100.0% of communities
100.0% of communities have no open violations
Water Systems
55
Active community systems
Median Lead Level
0.94 ppb
6% of EPA action level
Fully Compliant
100%
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 Hawaii

✓ Cleanest Water
Kawela Bay
Honolulu County
0.0 ppb A
Urban Honolulu
Honolulu County
0.0 ppb A
East Honolulu
Honolulu County
0.0 ppb A
Pearl City
Honolulu County
0.0 ppb A
Waipahu
Honolulu County
0.0 ppb A
Hilo
Hawaii County
0.0 ppb A
⚠ Needs Attention
Keokea
Maui County
3.7 ppb C
Olinda
Maui County
3.7 ppb C
Kula
Maui County
1.7 ppb B
Honomu
Hawaii County
0.0 ppb B
Honalo
Hawaii County
0.0 ppb B
Kailua
Hawaii County
0.0 ppb B

Water Quality by County

4 of 4
Sort:
CountySystemsLead LevelViolationsGrade
Honolulu County 49 No data 0 A
Hawaii County 41 9.0 ppb 0 A
Maui County 28 0.9 ppb 0 A
Kauai County 23 No data 0 A

About Hawaii Drinking Water

Hawaii is served by 55 community water systems covering 141 communities across 4 counties. 100.0% have no open violation on record.

Lead was detected in 18 communities, with a median of 0.94 ppb — 6% of the federal action level. A further 123 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 78.0% of communities here, and 0 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 Hawaii tap water safe to drink? ▼
100.0% of communities have no open violation on record. No community has PFAS above the federal limit on record.
Does Hawaii have a lead problem? ▼
0 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 123 communities report no detection at all.
How complete is the data for Hawaii? ▼
Lead results are reported for 100.0% of communities and PFAS for 78.0%. Where a figure is missing it is shown as not reported rather than assumed safe.
How does Hawaii 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.