STATE / TERRITORY LEDGER
Hawaii drinking water system records
EPA’s September 2026 export lists 45 active community water systems in Hawaii, with 4 current-violation flags and 0 serious-violator flags among covered systems serving at least 2,500 people.
Source: EPA SDWIS system-search export · Active community systems · Snapshot 13 Sep 2026
Systems45active CWS · pop. 2,500+
Population served1,463,297reported total; may overlap
Current violation flag8.9%4 systems
Serious-violator flag0.0%0 systems
01 / LARGEST SYSTEMS
Hawaii community water systems
EPA’s covered Hawaii records include 45 active community systems reporting a combined population-served total of 1,463,297, which may overlap.
Population served is a system-reported service figure. It is not a count of unique state residents.
| Water system | Population served | Primary source | Current export status |
|---|---|---|---|
| Hnl-Windward-Pearl HarborHI0000331 | 631,389 | Ground water | No current violation flagged |
| Waipahu-Ewa-WaianaeHI0000335 | 217,479 | Ground water | No current violation flagged |
| WailukuHI0000212 | 74,511 | Surface water | No current violation flagged |
| Joint Base Pearl Harbor-HickamHI0000360 | 65,230 | Ground water | Other current violation flag |
| MililaniHI0000367 | 50,573 | Ground water | No current violation flagged |
| HiloHI0000101 | 39,477 | Ground water | No current violation flagged |
| Schofield BarracksHI0000345 | 37,920 | Ground water | No current violation flagged |
| Lihue-KapaaHI0000400 | 34,854 | Surface water | No current violation flagged |
| MakawaoHI0000213 | 29,868 | Surface water | No current violation flagged |
| North KonaHI0000131 | 29,581 | Ground water | Current monitoring/reporting flag |
| WahiawaHI0000333 | 23,348 | Ground water | No current violation flagged |
| LahainaHI0000214 | 20,065 | Surface water | No current violation flagged |
| Marine Corps Base HawaiiHI0000356 | 16,300 | Ground water purchased | No current violation flagged |
| Kalaheo-KoloaHI0000434 | 12,660 | Ground water | No current violation flagged |
| WaikoloaHI0000135 | 12,100 | Ground water | No current violation flagged |
| Waipio HeightsHI0000334 | 11,516 | Ground water | No current violation flagged |
| Waialua-HaleiwaHI0000332 | 9,996 | Ground water | No current violation flagged |
| South KohalaHI0000130 | 9,612 | Surface water | No current violation flagged |
| KaanapaliHI0000205 | 8,000 | Ground water | No current violation flagged |
| Upper KulaHI0000215 | 7,686 | Surface water | No current violation flagged |
| Fort ShafterHI0000341 | 7,067 | Ground water | No current violation flagged |
| PrincevilleHI0000428 | 6,911 | Ground water | No current violation flagged |
| South KonaHI0000132 | 6,512 | Ground water | No current violation flagged |
| Nctams EastpacHI0000357 | 6,470 | Ground water | No current violation flagged |
| Olaa-Mountain ViewHI0000112 | 6,467 | Ground water | No current violation flagged |
| AliamanuHI0000337 | 6,406 | Ground water purchased | Other current violation flag |
| Kekaha-WaimeaHI0000406 | 5,998 | Ground water | No current violation flagged |
| Hanapepe-EleeleHI0000404 | 5,592 | Ground water | No current violation flagged |
| Laie Water CompanyHI0000325 | 5,577 | Ground water | No current violation flagged |
| Tripler Army Medical CntrHI0000346 | 5,555 | Ground water | No current violation flagged |
| Barbers PointHI0000355 | 5,256 | Ground water | No current violation flagged |
| North KohalaHI0000129 | 4,933 | Ground water | No current violation flagged |
| Waialee-Sunset BeachHI0000366 | 4,916 | Ground water | No current violation flagged |
| HainaHI0000161 | 4,563 | Ground water | No current violation flagged |
| Hawaii Volcanoes Nat.ParkHI0000146 | 4,201 | Ground water | No current violation flagged |
| KapaluaHI0000204 | 4,200 | Ground water | No current violation flagged |
| Kamehameha SchoolsHI0000319 | 4,000 | Ground water | No current violation flagged |
| KaunakakaiHI0000234 | 3,702 | Ground water | No current violation flagged |
| Hawaiian BeachesHI0000117 | 3,546 | Ground water | No current violation flagged |
| Lower KulaHI0000247 | 3,522 | Surface water | No current violation flagged |
| The Queen'S Medical CenterHI0000312 | 3,440 | Ground water | No current violation flagged |
| KilaueaHI0000407 | 3,420 | Ground water | No current violation flagged |
| Lanai CityHI0000237 | 3,200 | Ground water | Current monitoring/reporting flag |
| Waiohinu-NaalehuHI0000108 | 2,948 | Ground water | No current violation flagged |
| KahukuHI0000365 | 2,730 | Ground water | No current violation flagged |
02 / CITY REPORTS
Hawaii city water-system reports
Hawaii has 15 city reports meeting the publication threshold for covered systems or reported population served.
03 / COUNTY REPORTS
Hawaii county water-system reports
Hawaii has 4 county reports meeting the publication threshold for covered systems or reported population served.