Hawaii tap water quality

118 active community water systems.

Largest water systems

GradeSystemPeopleHealth violations (5y)
AHonolulu Board of Water Supply (Windward–Pearl Harbor)631,3890
AWaipahu-Ewa-Waianae217,4790
AWailuku74,5110
AJoint Base Pearl Harbor-Hickam65,2300
AMililani50,5730
AHilo39,4770
ASchofield Barracks37,9200
ALihue-Kapaa34,8540
AMakawao29,8680
ANorth Kona29,5810
AWahiawa23,3480
ALahaina20,0650
AMarine Corps Base Hawaii16,3000
AKalaheo-Koloa12,6600
AWaikoloa12,1000
AWaipio Heights11,5160
AWaialua-Haleiwa9,9960
ASouth Kohala9,6120
AKaanapali8,0000
AUpper Kula7,6860
AFort Shafter7,0670
APrinceville6,9110
ASouth Kona6,5120
ANctams Eastpac6,4700
AOlaa-Mountain View6,4670
AAliamanu6,4060
AKekaha-Waimea5,9980
AHanapepe-Eleele5,5920
ALaie Water Company5,5770
ATripler Army Medical Cntr5,5550
ABarbers Point5,2560
ANorth Kohala4,9330
AWaialee-Sunset Beach4,9160
AHaina4,5630
AHawaii Volcanoes Nat.park4,2010
AKapalua4,2000
AKamehameha Schools4,0000
AKaunakakai3,7020
AHawaiian Beaches3,5460
ALower Kula3,5220
AThe Queen's Medical Center3,4400
AKilauea3,4200
BLanai City3,2000
AWaiohinu-Naalehu2,9480
AKahuku2,7300
AAnahola2,4730
AHoolehua2,4000
APapaikou2,2030
AKaupulehu1,9450
ALalamilo1,8950

Most issues (systems serving 10,000+)

A

Makawao

Serves 29,868 people · Surface water · Full report →
No health-based violations in the last 5 years; 2 monitoring/reporting violations; PFAS tested (UCMR 5), none above federal limits; Latest lead 90th percentile on file is from 2019 (older than 5 years, not graded).
A

Marine Corps Base Hawaii

Serves 16,300 people · Groundwater · Full report →
No health-based violations in the last 5 years; 2 monitoring/reporting violations; PFAS tested (UCMR 5), none above federal limits; Lead 90th percentile below the action level (2021).
A

Joint Base Pearl Harbor-Hickam

Serves 65,230 people · Groundwater · Full report →
No health-based violations in the last 5 years; 1 monitoring/reporting violation; 1 not yet resolved; PFAS tested (UCMR 5), none above federal limits; Lead 90th percentile below the action level (2023).
A

North Kona

Serves 29,581 people · Groundwater · Full report →
No health-based violations in the last 5 years; 1 monitoring/reporting violation; 1 not yet resolved; PFAS tested (UCMR 5), none above federal limits; Lead 90th percentile below the action level (2021).
A

Honolulu Board of Water Supply (Windward–Pearl Harbor)

Serves 631,389 people · Groundwater · Full report →
No health-based violations in the last 5 years; PFAS tested (UCMR 5), none above federal limits; Latest lead 90th percentile on file is from 2018 (older than 5 years, not graded).
A

Waipahu-Ewa-Waianae

Serves 217,479 people · Groundwater · Full report →
No health-based violations in the last 5 years; PFAS tested (UCMR 5), none above federal limits; Latest lead 90th percentile on file is from 2018 (older than 5 years, not graded).
A

Wailuku

Serves 74,511 people · Surface water · Full report →
No health-based violations in the last 5 years; PFAS tested (UCMR 5), none above federal limits; Latest lead 90th percentile on file is from 2018 (older than 5 years, not graded).
A

Mililani

Serves 50,573 people · Groundwater · Full report →
No health-based violations in the last 5 years; PFAS tested (UCMR 5), none above federal limits; Latest lead 90th percentile on file is from 2018 (older than 5 years, not graded).
A

Hilo

Serves 39,477 people · Groundwater · Full report →
No health-based violations in the last 5 years; PFAS tested (UCMR 5), none above federal limits; Lead 90th percentile below the action level (2022).
A

Schofield Barracks

Serves 37,920 people · Groundwater · Full report →
No health-based violations in the last 5 years; PFAS tested (UCMR 5), none above federal limits; Lead 90th percentile below the action level (2022).
A

Lihue-Kapaa

Serves 34,854 people · Surface water · Full report →
No health-based violations in the last 5 years; PFAS tested (UCMR 5), none above federal limits; Lead 90th percentile below the action level (2021).
A

Wahiawa

Serves 23,348 people · Groundwater · Full report →
No health-based violations in the last 5 years; PFAS tested (UCMR 5), none above federal limits; Latest lead 90th percentile on file is from 2018 (older than 5 years, not graded).
A

Lahaina

Serves 20,065 people · Surface water · Full report →
No health-based violations in the last 5 years; PFAS tested (UCMR 5), none above federal limits; Latest lead 90th percentile on file is from 2018 (older than 5 years, not graded).
A

Kalaheo-Koloa

Serves 12,660 people · Groundwater · Full report →
No health-based violations in the last 5 years; PFAS tested (UCMR 5), none above federal limits; Lead 90th percentile below the action level (2021).
A

Waikoloa

Serves 12,100 people · Groundwater · Full report →
No health-based violations in the last 5 years; PFAS tested (UCMR 5), none above federal limits; Lead 90th percentile below the action level (2021).
A

Waipio Heights

Serves 11,516 people · Groundwater · Full report →
No health-based violations in the last 5 years; PFAS tested (UCMR 5), none above federal limits; Latest lead 90th percentile on file is from 2018 (older than 5 years, not graded).

Cities

AieaAnaholaAnahola Farm Lots (Dho)Downtown HonoluluEleeleEwa BeachHaena-WainihaHaikuHainaHakalau-WaileaHaleakalaHaleiwaHanaHanaleiHanalei (Dow)Hanapepe-Eleele (Dow)HauulaHawaii National ParkHawaiian Shores DhoHawiHiloHolualoaHonaunauHonokaaHonoluluHonolulu-Windward-PearlharborHonomuHoolehuaHvnp (Dho)JbphhKaaawaKaanapali (Dho)Kaeleku Ag Park HanaKahakuloa HomesteadKahana ValleyKahili Mountain ParkKahukuKahuku Air BaseKahuluiKailuaKailua KonaKailua MauiKalaheoKalapana (Dws)KalaupapaKamuelaKaneoheKapaaKapaauKapalamaKapalua (Dho)KapoleiKaumakaniKaunakakaiKawaihaeKawelaKeaauKealakekuaKealiaKealia (Dho)Keanae (Dws)KeauhouKekahaKekaha (Dow)Keola Hana-Hotel DhoKiheiKilaueaKilauea (Dow)Kohala Joint VentureKoloaKonaKualapuuKukuihaeleKulaKuniaKurtistownLahainaLaieLalamiloLanaiLanai CityLaupahoehoeLawaiLihueLihue-KapaaMahanalua NuiMakawaoMakenaMaunaloaMaunaloa, MolokaiMililaniMililani BwsMoanaluaMokuleiaMountain ViewNaalehuNahikuNinoleNiuliiNorth KohalaNorth KonaOcean ViewOlaa-Mt.viewOlowaluOokalaPaauiloPahalaPahoaPaiaPapaaloaPapaikouPearl CityPearl HarborPepeekeoPmrf Housing (Dho)PrincevillePrinceville (Dho)PukalaniPunaluu (Dho)PuunenePuuwaawaa Ranch DhoSalt LakeSchofield BarracksSouth KohalaSouth KonaSunset BeachTripler Army Medical CenterUalapueWahiawaWaialuaWaialua-HaleiwaWaianaeWaikii Ranch (Dho)WaikoloaWaikoloa (Dho)WailukuWaimanaloWaimeaWaiohinu-NaalehuWaipahuWaipahu-Ewa-WaianaeWaipio