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Tap water quality report

Hilo

EPA monitoring tested this supplier for 114 contaminants and detected 12. A detection doesn't automatically mean the water is unsafe — the level and EPA source for each is below.

114
contaminants tested
12
detected
39,477
people served
168
health-based violations
Hawaii rankingsLead in HawaiiPFAS in Hawaii
Water source
Ground water
Ownership
Local government
Counties served
Hawaii

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.

168
health-based violations
168
violations on file
0
still open
ViolationTypeStatusPeriod
TT Health-based Resolved 2009-01-01 → 2009-01-31
TT Health-based Resolved 2009-01-01 → 2009-01-31
TT Health-based Resolved 2009-01-01 → 2009-01-31
TT Health-based Resolved 2000-01-01
TT Health-based Resolved 2000-01-01
TT Health-based Resolved 2000-01-01
TT Health-based Resolved 2000-01-01
TT Health-based Resolved 2000-01-01
TT Health-based Resolved 2000-01-01
TT Health-based Resolved 2000-01-01

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
416.5 µg/L 4.2%
of the EPA limit 10000 µg/L
worst single sample: 420 µg/L
68/70 SYR4 2012–2019
Nitrate-Nitrite
413.5 µg/L 4.1%
of the EPA limit 10000 µg/L
worst single sample: 420 µg/L
34/35 SYR4 2012–2019
Copper
158.5 µg/L 12%
of the EPA limit 1300 µg/L
worst single sample: 207 µg/L
27/111 SYR4 2013–2019
Lead
0.0 mg/L 0%
of the EPA limit 0.0150 mg/L
 12/12 LCR 2022
Fluoride
237.5 µg/L 5.9%
of the EPA limit 4000 µg/L
worst single sample: 240 µg/L
6/35 SYR4 2012–2019
Bromodichloromethane
0.5200 µg/L
No EPA limit set
 1/17 SYR4 2012–2019
Bromoform
0.5700 µg/L
No EPA limit set
 1/17 SYR4 2012–2019
Chromium
1.3 µg/L 1.3%
of the EPA limit 100 µg/L
 1/9 SYR4 2014–2017
Dibromochloromethane
0.8100 µg/L
No EPA limit set
 1/17 SYR4 2012–2019
TTHM
1.9 µg/L 2.4%
of the EPA limit 80 µg/L
 1/17 SYR4 2012–2019
Total Haloacetic Acids (HAA5)
1.1 µg/L 1.8%
of the EPA limit 60 µg/L
 1/15 SYR4 2012–2019
Trichloroacetic Acid
1.1 µg/L
No EPA limit set
 1/15 SYR4 2012–2019
102 contaminants tested, none detected
1,1,1-Trichloroethane1,1,2-Trichloroethane1,1-Dichloroethylene1,2,4-Trichlorobenzene1,2-DIBROMO-3-CHLOROPROPANE1,2-Dichloroethane1,2-Dichloropropane11Cl-PF3OUdS2,3,7,8-TCDD2,4,5-TP2,4-D4:2 Fts6:2 Fts8:2 Fts9Cl-PF3ONSAdonaAntimony, TotalArsenicAsbestosAtrazineBhc-GammaBariumBenzeneBenzo(A)PyreneBeryllium, TotalChlorobenzeneCyanideCadmiumCarbofuranCarbon TetrachlorideChlordaneChloroformCombined Radium (-226 And -228)Combined UraniumDichloromethaneDalaponDi(2-ethylhexyl) AdipateDi(2-ethylhexyl) PhthalateDibromoacetic AcidDichloroacetic AcidDinosebDiquatEthylene DibromideEndothallEndrinEthylbenzeneGlyphosateGross Alpha, Excl. Radon And UGross Beta Particle ActivityHexachlorobenzeneHfpo-DaHeptachlorHeptachlor EpoxideHexachlorocyclopentadieneLassoLeadMercuryMethoxychlorMonobromoacetic AcidMonochloroacetic AcidNetfosaaNfdhaNmefosaaNitriteOxamylPfbaPFBSPfdaPfdoaPfeesaPfhpaPfhpsPfhxaPFHXSPfmbaPfmpaPFNAPFOAPFOSPfpeaPfpesPftaPftrdaPfunaPentachlorophenolPicloramSeleniumSimazineStyreneTetrachloroethyleneThallium, TotalTolueneTotal Polychlorinated Biphenyls (PCB)ToxapheneTrichloroethyleneVinyl ChlorideXylenes, Totalcis-1,2-DichloroethyleneLithiumO-DichlorobenzeneP-Dichlorobenzenetrans-1,2-Dichloroethylene

Utility contact

Contact
OKAMOTO, KEITH K.
Phone
808-961-8050

Frequently asked questions about Hilo

Is Hilo tap water safe to drink?

EPA monitoring detected 12 contaminants in Hilo'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 Hilo's water?

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

How many people does Hilo serve?

Hilo reports serving 39,477 people in Hawaii, per its EPA record.

Has Hilo had any water quality violations?

The EPA has 168 violations on file for Hilo, of which 168 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.