Water Service Outages in Hawaii by City
Only 7% of Hawaii's 118 community water systems have had a health-based EPA violation since 2015, one of the lowest shares of any state.
Hawaii drinking water record
Busiest year: 2015 (5 violations). Counted by the year the violation period began. Source: EPA SDWIS.
- Community water systems: 118 active systems serve about 1,507,181 people. 76 of them (64%) serve 3,300 people or fewer; 109 draw mainly on groundwater and 9 on surface water.
- Health-based violations since 2015: 16, at 8 systems (7% of all systems). That share is the lowest of the 50 states.
- Most common problems: surface water treatment (6); contaminant averages over the limit (1). Source: EPA SDWIS
- Largest system: Hnl-Windward-Pearl Harbor, about 631,389 people, with 0 health-based violations since 2015. Source: EPA SDWIS
- Housing age: the median Hawaii home was built in 1980 (US 1980). Source: US Census Bureau, ACS 2020–2024 (table B25035)
| System | People served | Main source | Health violations since 2015 |
|---|---|---|---|
| Hnl-Windward-Pearl Harbor | 631,389 | Groundwater | 0 |
| Waipahu-Ewa-Waianae | 217,479 | Groundwater | 0 |
| Wailuku | 74,511 | Surface water | 0 |
| Joint Base Pearl Harbor-Hickam | 65,230 | Groundwater | 0 |
| Mililani | 50,573 | Groundwater | 0 |
| Hilo | 39,477 | Groundwater | 0 |
Source: EPA SDWIS.
Hawaii is 1st of 4 (1 = lowest share). Source: EPA SDWIS.
Checked September 2026.
Who to call in Hawaii, city by city
4 Hawaii cities on this site and the water utility for each. What to do while you wait is in our water service outage guide.
- Honolulu Honolulu Board of Water Supply
- Hilo Hawaii County Department of Water Supply
- Kailua Honolulu Board of Water Supply
- Kaneohe Honolulu Board of Water Supply
Frequently asked questions
Is there a water service outage in Hawaii right now?
Not on this site: no reports from Hawaii in the last 24 hours.
How many public water systems are in Hawaii?
EPA records list 118 active community water systems in Hawaii, serving about 1,507,181 people. 64% serve 3,300 people or fewer.
How common are drinking water violations in Hawaii?
Since 2015, 8 of 118 community water systems in Hawaii (7%) have had at least one health-based violation, 16 in total.
What is the largest water system in Hawaii?
Hnl-Windward-Pearl Harbor, which EPA records list as serving about 631,389 people.
Report counts are user-submitted; other figures name their official source. How our data works
Cities in Hawaii with Water Service Outages Information
Hilo
no reports in the last 24 hours · pop. 45,289
Hawaii County Department of Water Supply
Honolulu
no reports in the last 24 hours · pop. 347,397
Honolulu Board of Water Supply
Kailua
no reports in the last 24 hours · pop. 38,758
Honolulu Board of Water Supply
Kaneohe
no reports in the last 24 hours · pop. 35,871
Honolulu Board of Water Supply