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Tap water quality report

Mililani

EPA monitoring tested this supplier for 114 contaminants and detected 10. A detection doesn't automatically mean the water is unsafe — the level and EPA source for each is below.

114
contaminants tested
10
detected
50,573
people served
0
health-based violations
Hawaii rankingsLead in HawaiiPFAS in Hawaii
Water source
Ground water
Ownership
Local government
Counties served
Honolulu

Compliance record

Formal violations the EPA has on file for this supplier. A health-based violation means a contaminant limit or a required treatment was breached; the rest are monitoring or reporting failures — still violations, but not a measured health risk.

0
health-based violations
42
violations on file
0
still open
ViolationTypeStatusPeriod
MR Monitoring Archived 2000-04-01 → 2000-04-30
MR Monitoring Archived 2000-04-01 → 2000-04-30
MR Monitoring Archived 2000-04-01 → 2000-04-30
MR Monitoring Archived 2000-01-01 → 2000-03-31
MR Monitoring Archived 2000-01-01 → 2000-03-31
MR Monitoring Archived 2000-01-01 → 2000-03-31
MR Monitoring Archived 1999-10-01 → 1999-12-31
MR Monitoring Archived 1999-10-01 → 1999-12-31
MR Monitoring Archived 1999-10-01 → 1999-12-31
MR Monitoring Archived 1999-07-01 → 1999-09-30

Other contaminants detected

Each bar shows the measured level as a share of the EPA limit: green is well under, amber is close to it, red is over. For lead and copper the limit applies to exactly the 90th-percentile figure shown, so red there means a real exceedance. For everything else the limit applies to a running annual average while the figure is the 95th percentile of this system's samples — over 100% is worth reading, but is not by itself a violation. Where a single sample came in higher than that percentile, it is noted under the bar. Formal violations are listed separately.
ContaminantLevel vs EPA limitDetection rateSourcePeriod
Nitrate
2200 µg/L 22%
of the EPA limit 10000 µg/L
worst single sample: 2600 µg/L
58/58 SYR4 2012–2019
Nitrate-Nitrite
2200 µg/L 22%
of the EPA limit 10000 µg/L
worst single sample: 2600 µg/L
26/26 SYR4 2012–2019
Fluoride
101 µg/L 2.5%
of the EPA limit 4000 µg/L
worst single sample: 110 µg/L
19/29 SYR4 2012–2019
Lead
0.0 mg/L 0%
of the EPA limit 0.0150 mg/L
 9/9 LCR 2018
Chromium
2.055 µg/L 2.1%
of the EPA limit 100 µg/L
worst single sample: 2.3 µg/L
8/10 SYR4 2013–2019
1,2-DIBROMO-3-CHLOROPROPANE
0.2770 µg/L 139%
of the EPA limit, at the 95th percentile of samples — 0.2000 µg/L
worst single sample: 0.2800 µg/L
7/69 SYR4 2012–2019
Copper
12.25 µg/L 0.9%
of the EPA limit 1300 µg/L
worst single sample: 13 µg/L
6/10 SYR4 2013–2019
Barium
3.38 µg/L 0.2%
of the EPA limit 2000 µg/L
worst single sample: 3.5 µg/L
4/10 SYR4 2013–2019
Combined Radium (-226 And -228)
1.1 pCi/L 22%
of the EPA limit 5 pCi/L
 1/9 SYR4 2013–2019
Gross Alpha, Excl. Radon And U
1.2 pCi/L 8%
of the EPA limit 15 pCi/L
 1/8 SYR4 2013–2019
104 contaminants tested, none detected
1,1,1-Trichloroethane1,1,2-Trichloroethane1,1-Dichloroethylene1,2,4-Trichlorobenzene1,2-Dichloroethane1,2-Dichloropropane11Cl-PF3OUdS2,3,7,8-TCDD2,4,5-TP2,4-D4:2 Fts6:2 Fts8:2 Fts9Cl-PF3ONSAdonaAntimony, TotalArsenicAsbestosAtrazineBhc-GammaBenzeneBenzo(A)PyreneBeryllium, TotalBromodichloromethaneBromoformChlorobenzeneCyanideCadmiumCarbofuranCarbon TetrachlorideChlordaneChloroformCombined UraniumDichloromethaneDalaponDi(2-ethylhexyl) AdipateDi(2-ethylhexyl) PhthalateDibromoacetic AcidDibromochloromethaneDichloroacetic AcidDinosebDiquatEthylene DibromideEndothallEndrinEthylbenzeneGlyphosateGross Beta Particle ActivityHexachlorobenzeneHfpo-DaHeptachlorHeptachlor EpoxideHexachlorocyclopentadieneLassoLeadMercuryMethoxychlorMonobromoacetic AcidMonochloroacetic AcidNetfosaaNfdhaNmefosaaNitriteOxamylPfbaPFBSPfdaPfdoaPfeesaPfhpaPfhpsPfhxaPFHXSPfmbaPfmpaPFNAPFOAPFOSPfpeaPfpesPftaPftrdaPfunaPentachlorophenolPicloramSeleniumSimazineStyreneTTHMTetrachloroethyleneThallium, TotalTolueneTotal Haloacetic Acids (HAA5)Total Polychlorinated Biphenyls (PCB)ToxapheneTrichloroacetic AcidTrichloroethyleneVinyl ChlorideXylenes, Totalcis-1,2-DichloroethyleneLithiumO-DichlorobenzeneP-Dichlorobenzenetrans-1,2-Dichloroethylene

Utility contact

Contact
KAWATA, ERWIN
Phone
808-748-5080
Email
[email protected]

Frequently asked questions about Mililani

Is Mililani tap water safe to drink?

EPA monitoring detected 10 contaminants in Mililani's water. A detection isn't the same as a violation — most levels are within federal limits. See each level and source above, and the utility's annual Consumer Confidence Report for its official compliance status.

What contaminants were detected in Mililani's water?

EPA monitoring detected Nitrate, Nitrate-Nitrite, Fluoride, Lead, Chromium, and others. The full list with the level and data source for each is above.

How many people does Mililani serve?

Mililani reports serving 50,573 people in Hawaii, per its EPA record.

Has Mililani had any water quality violations?

The EPA has 42 violations on file for Mililani, of which 0 are health-based (a contaminant limit or required treatment was breached) and 0 remain open. The rest are monitoring or reporting failures.

Where does this data come from?

Every figure is official EPA drinking-water monitoring — the Lead & Copper Rule, the UCMR-5 nationwide testing program, and the EPA Six-Year Review — not our own testing. Each number is labelled with its source and period.