WaterVerge

Is Hoolehua, HI Tap Water Safe to Drink?

Graded A, with 2 unresolved violations on record. See what was cited — and what it means for your tap. What to do next ↓

2K residents served 1 water system PWSID: HI0000230
Overall Score
93.2 / 100
Violations
2 active
Last Updated
May 2026
Source
Groundwater
#30 of 66 in Hawaii Top 6% nationally
State
Moderate data confidence
Reviewed by WaterVerge Editorial Team · Last updated May 2026
AGRADE
Water Quality Grade
93.2/100
waterverge.com
A 93.2/100

Hoolehua, HI — Water Quality Report

Hoolehua's drinking water received a grade of A (93.2 out of 100), indicating excellent water quality. The city's 1 water system serves approximately 2,400 residents using groundwater.

Lead levels were measured at 0.0 ppb (90th percentile), well within EPA limits. This system has not yet been tested for PFAS under the EPA UCMR 5 program.

The system has 13 violations on record, including 0 health-based violations. 2 remain unresolved.

Data last updated: May 2026 · Source: EPA SDWIS, UCMR 5
Analysis

What to know about Hoolehua's water

Hoolehua ranks #30 out of 66 cities in Hawaii for water quality, placing it mid-range in the state.

Hoolehua relies on groundwater, which is generally less vulnerable to surface contamination but can be affected by naturally occurring minerals like arsenic and nitrate, as well as agricultural and industrial runoff.

As a small community water system, Hoolehua may have fewer resources for advanced treatment technologies and infrastructure upgrades compared to larger utilities.

Quality Breakdown

Water quality score

See methodology →
93.2 out of 100 Grade A
A: 90-100
B: 74-89
C: 60-73
F: <50
How is this calculated?
Violations
43.2/45
A
Historical violation record including health-based and monitoring violations.
Lead & Copper
20/20
A
Lead at 0.0 ppb (90th percentile).
Contaminants
17/20
B
PFAS + legacy contaminant analysis.
Compliance
8/10
B
Monitoring and reporting compliance with EPA regulations.
Source Risk
5/5
A
Water source: Groundwater.
Water Safety

Is Hoolehua, HI water safe to drink?

Use Caution

Hoolehua's tap water meets most EPA standards but has areas that warrant attention. With a grade of A (93.2/100), some contaminant levels or compliance issues suggest that residents may benefit from additional filtration. The city's 1 water system serves approximately 2,400 residents using groundwater (wells).

2
Active Violations
0.0 ppb
Lead (90th %ile)
9 events
Disaster History

Recent water quality updates for Hoolehua

A timeline of significant water quality events, violations, and data updates.

Update
Water quality data updated

Latest EPA compliance and testing data incorporated into Hoolehua's water quality assessment. Grade: A (93.2/100).

Disaster
SEVERE STORMS, FLOODING, AND LANDSLIDES

Federal disaster declaration (FEMA DR-4604). Flood event — may have impacted local water infrastructure.

Disaster
HURRICANE DOUGLAS

Federal disaster declaration (FEMA DR-3529). Hurricane event — may have impacted local water infrastructure.

Violation
2 drinking water violations recorded

Contaminants: TTHM, Total Haloacetic Acids (HAA5).

Violation
3 drinking water violations recorded

Contaminants: TTHM, Lead and Copper Rule, Total Haloacetic Acids (HAA5).

Violation
1 drinking water violation recorded

Contaminants: Coliform (TCR).

Key contaminant findings

Based on the most recent EPA sampling data for Hoolehua's water supply.

Lead Within Limits
Detected: 0.0 ppb Limit: 15 ppb (EPA Action Level)

Well within EPA limits.

Violation history

Hoolehua's water system has 13 total violations on record, including 0 health-based violations. 2 remain unresolved.

MROther
Most recent violations:
Jan 2020 TTHM Resolved
Jan 2020 Total Haloacetic Acids (HAA5) Resolved
Jan 2016 TTHM Resolved
Jan 2016 Lead and Copper Rule Open
Jan 2016 Total Haloacetic Acids (HAA5) Resolved

Flood & environmental risk

Maui County has experienced 9 federally declared disasters since 1968. Flooding and severe storms can overwhelm water treatment plants, cause sewage overflows, and introduce agricultural runoff, bacteria, and sediment into drinking water supplies. Local water sources include Waikolu Str Blw Pipe Nr Kalaupapa, Molokai, Waihanau Stream Nr Kalaupapa, Molokai, Kaunakakai Gulch At Altitude 75 Feet, Molokai, Ef Kawela Gulch Nr Kamalo, Molokai, Kawela Gulch Near Moku, Molokai.

SEVERE STORMS, FLOODING, AND LANDSLIDES
Flood FEMA DR-4604
HURRICANE DOUGLAS
Hurricane FEMA DR-3529
HURRICANE LANE
Hurricane FEMA DR-4395

Where does Hoolehua's water come from?

Hoolehua's drinking water comes from groundwater (wells), supplied by 1 water system serving approximately 2,400 people. Groundwater is generally less susceptible to surface contamination but can contain naturally occurring contaminants like arsenic, radon, and nitrate. Nearby water bodies include Waikolu Str Blw Pipe Nr Kalaupapa, Molokai (river), Waihanau Stream Nr Kalaupapa, Molokai (river), Kaunakakai Gulch At Altitude 75 Feet, Molokai (river), Ef Kawela Gulch Nr Kamalo, Molokai (river), Kawela Gulch Near Moku, Molokai (river).

What Hoolehua residents can do

Request your utility's CCR

Your water utility is required to publish an annual Consumer Confidence Report (CCR) with detailed testing results. Ask for the latest copy or check your utility's website.

Monitor alerts during storms

Hoolehua's area has a history of flooding. After severe weather, watch for boil water advisories from your local utility.

Data: EPA SDWIS, UCMR 5 (PFAS), FEMA, NOAA. Last updated May 2026.

Contaminant Alerts

Top contaminants to know

View all ↓
Lead (90th percentile)
Inorganic / Heavy Metal
Safe
0.0 ppb
EPA Action Level: 15 ppb · 0% of limit
Safe Level
Compliance Record

Violation summary

13
Total violations
0
Health-based
2
Active / unresolved
Jan 2020
Most recent violation
Compliance Record

Violations & advisories

13 Total
2 Active
0 Health-based
11 Resolved
2 SNC
Violations by category
Total Coliform Rule
6
Stage 2 Disinfectants and Disinfection Byproducts Rule
4
Lead and Copper Rule
1
Miscellaneous Other Rules
1
Jan 2016 Active
Lead and Copper Rule
Monitoring & Reporting
Monitoring & Reporting 0
Active
Compliance Violation
Monitoring 0
Jan 2020 Resolved
TTHM
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2020
Jan 2020 Resolved
Total Haloacetic Acids (HAA5)
Monitoring & Reporting
Monitoring & Reporting Resolved Dec 2020
Jan 2016 Resolved
TTHM
Monitoring & Reporting
SNC Monitoring & Reporting Resolved Dec 2016
Jan 2016 Resolved
Total Haloacetic Acids (HAA5)
Monitoring & Reporting
SNC Monitoring & Reporting Resolved Dec 2016
Feb 2010 Resolved
Coliform (TCR)
Monitoring & Reporting
Monitoring & Reporting Resolved Feb 2010
May 1988 Resolved
Coliform (Pre-TCR)
Other Violation Resolved May 1988
Jan 1987 Resolved
Coliform (Pre-TCR)
Other Violation Resolved Jan 1987
Apr 1983 Resolved
Coliform (Pre-TCR)
Other Violation Resolved May 1983
Sep 1982 Resolved
Coliform (Pre-TCR)
Other Violation Resolved Dec 1982
Jun 1981 Resolved
Coliform (Pre-TCR)
Other Violation Resolved Jul 1981
Jun 1981 Resolved
Miscellaneous Other Rules
Other Violation Resolved Sep 1981
Environmental Risk

Flood & disaster history

9
Declared disasters
May 2021
Most recent
Hurricane
Most common type

Maui County has experienced 9 federally declared disasters since 1968. Flooding and severe weather can compromise water treatment infrastructure and introduce contaminants into drinking water supplies.

May 2021
SEVERE STORMS, FLOODING, AND LANDSLIDES
Flood FEMA #4604
Jul 2020
HURRICANE DOUGLAS
Hurricane FEMA #3529
Sep 2018
HURRICANE LANE
Hurricane FEMA #4395
Sep 2018
TROPICAL STORM OLIVIA
Hurricane FEMA #3404
Aug 2018
HURRICANE LANE
Hurricane FEMA #3399
Sep 1992
HURRICANE INIKI
Hurricane FEMA #961

Full contaminants report

Contaminant Detected Level EPA Limit Unit Category Status
Lead (90th percentile) 0.0 15 ppb Inorganic Safe
Data source: EPA SDWIS, UCMR 5, local utility CCR.

Lead level trend (90th percentile)

EPA action level: 15 ppb
Lead has decreased by 5.0 ppb from 2009 (5.0 ppb) to 2020 (0.0 ppb).
Infrastructure

Water source & infrastructure

Primary Source
Groundwater
Operator
State
Population Served
2,400
Water Systems
1
Water Source

Where Hoolehua's water comes from

Groundwater

Hoolehua's drinking water is drawn from underground aquifers through wells.

Groundwater is naturally filtered through rock and soil layers, generally requiring less treatment than surface water. However, it can contain naturally occurring contaminants like arsenic, radon, and minerals.

Agricultural activity, septic systems, and industrial operations near well fields can introduce nitrates, pesticides, and volatile organic compounds.

The system is operated by state ownership and serves approximately 2,400 people through 1 water system.

Local Hydrology

Water bodies near Hoolehua

Hoolehua is located near 5 notable water bodies. These water bodies contribute to the regional watershed and may indirectly affect groundwater quality.

Waikolu Str Blw Pipe Nr Kalaupapa, Molokai
river
Waihanau Stream Nr Kalaupapa, Molokai
river
Kaunakakai Gulch At Altitude 75 Feet, Molokai
river
Ef Kawela Gulch Nr Kamalo, Molokai
river
Kawela Gulch Near Moku, Molokai
river
Infrastructure

Water systems serving Hoolehua

System Name PWSID Population Source
HOOLEHUA HI0000230 2,400 GW
Regional Comparison

How Hoolehua compares

Full Hawaii rankings →

Hoolehua's score of 93.2/100 is on par with the average of 92/100 among major Hawaii cities. It outscores 7 of 10 nearby cities.

Hoolehua (this city)
93.2
Wailuku
91.4
Hawaii avg
92
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Frequently asked questions

Is Hoolehua, HI tap water safe to drink?

Hoolehua's water quality earned a grade of A (93.2/100). The water generally meets EPA standards and is considered safe for consumption. The city ranks #30 out of 66 cities tested in Hawaii.

What contaminants are in Hoolehua's water?

Lead was measured at 0.0 ppb (90th percentile). 13 violations are on record.

How is Hoolehua's water quality grade calculated?

The grade is based on four factors: violation history (40%), lead and copper levels (25%), PFAS contamination (25%), and regulatory compliance (10%). The score is also adjusted based on how complete the available data is. See our methodology page for full details.

Do I need a water filter in Hoolehua?

Based on current data, basic filtration should suffice for additional peace of mind.

Where does Hoolehua's water come from?

Hoolehua's water is sourced from Groundwater. The city has 1 water system serving approximately 2,400 residents.

Is Hoolehua's groundwater at risk of contamination?

Hoolehua uses groundwater, which can be affected by naturally occurring contaminants like arsenic, radon, and nitrate, as well as agricultural runoff and industrial activity. The system has 13 violations on record that may relate to groundwater quality. Groundwater systems are generally less susceptible to surface contamination but should be monitored for emerging contaminants like PFAS.

How does Hoolehua's water compare to other cities?

Hoolehua ranks #30 out of 66 cities in Hawaii (better than 55% of state cities) and #933 out of 15744 cities nationally (94th percentile). The grade of A reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.

Does Hoolehua's small water system affect quality?

Hoolehua's system serves approximately 2,400 residents. Small community water systems (under 3,300 people) may have fewer financial resources for infrastructure upgrades and advanced treatment technologies. However, they are held to the same EPA drinking water standards as larger systems. This system has 13 violations on record.