Is Papaikou, HI Tap Water Safe to Drink?
Graded A-, with 1 unresolved violation on record. See what was cited — and what it means for your tap. What to do next ↓
89.7/100
waterverge.com Papaikou, HI — Water Quality Report
Papaikou's drinking water received a grade of A- (89.7 out of 100), indicating good water quality. The city's 1 water system serves approximately 2,203 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 2 violations on record, including 0 health-based violations. 1 remains unresolved.
What to know about Papaikou's water
Papaikou ranks #46 out of 66 cities in Hawaii for water quality, placing it below average in the state.
Papaikou 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, Papaikou may have fewer resources for advanced treatment technologies and infrastructure upgrades compared to larger utilities.
Water quality score
See methodology →Is Papaikou, HI water safe to drink?
Papaikou's tap water meets most EPA standards but has areas that warrant attention. With a grade of A- (89.7/100), some contaminant levels or compliance issues suggest that residents may benefit from additional filtration. The city's 1 water system serves approximately 2,203 residents using groundwater (wells).
Recent water quality updates for Papaikou
A timeline of significant water quality events, violations, and data updates.
Latest EPA compliance and testing data incorporated into Papaikou's water quality assessment. Grade: A- (89.7/100).
Contaminants: Coliform (Pre-TCR).
Key contaminant findings
Based on the most recent EPA sampling data for Papaikou's water supply.
Well within EPA limits.
Violation history
Papaikou's water system has 2 total violations on record, including 0 health-based violations. 1 remain unresolved.
Where does Papaikou's water come from?
Papaikou's drinking water comes from groundwater (wells), supplied by 1 water system serving approximately 2,203 people. Groundwater is generally less susceptible to surface contamination but can contain naturally occurring contaminants like arsenic, radon, and nitrate. Nearby water bodies include Wailuku River At Piihonua (river), Honolii Stream Nr Papaikou (river).
What Papaikou residents can do
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.
Data: EPA SDWIS, UCMR 5 (PFAS), FEMA, NOAA. Last updated May 2026.
Top contaminants to know
View all ↓Violation summary
Violations & advisories
Top industrial polluters within 10 miles of Papaikou
Industrial polluters nearby
Reported releases to surface water by facilities near Papaikou, ranked by pounds discharged annually.
| Facility | Top chemical | To surface water (lbs/yr) | Distance |
|---|---|---|---|
HILL GENERATING STATION HILO, HI96720 | — | — | 6.4 mi |
ALOHA PETROLEUM LLC-HILO WEST TERMINAL HILO, HI96720 | — | — | 5.1 mi |
Source: EPA Toxic Release Inventory (TRI) 2023
Full contaminants report
| Contaminant | Detected Level | EPA Limit | Unit | Category | Status |
|---|---|---|---|---|---|
| Lead (90th percentile) LeadHeavy Metal A toxic heavy metal that can leach into drinking water from older pipes, solder, and fixtures. No amount of lead in water is considered safe. Health EffectsBrain and nervous system damage in children, kidney damage, high blood pressure, and reproductive problems in adults. EPA Limit15 ppb action level Common SourcesCorrosion of lead pipes, lead solder, brass faucets, and household plumbing. | 0.0 | 15 | ppb | Inorganic | Safe |
Lead level trend (90th percentile)
See how Papaikou compares by contaminant
Explore where Papaikou ranks among all Hawaii cities for specific contaminants.
Water source & infrastructure
Where Papaikou's water comes from
Papaikou'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 local government ownership and serves approximately 2,203 people through 1 water system.
Water bodies near Papaikou
Papaikou is located near 2 notable water bodies. These water bodies contribute to the regional watershed and may indirectly affect groundwater quality.
Water systems serving Papaikou
| System Name | PWSID | Population | Source |
|---|---|---|---|
| PAPAIKOU | HI0000107 | 2,203 | GW |
How Papaikou compares
Full Hawaii rankings →Papaikou's score of 89.7/100 is on par with the average of 92/100 among major Hawaii cities. It outscores 2 of 10 nearby cities. 8 of 10 nearby cities score higher.
Nearby cities
View Hawaii rankings →About Papaikou, HI
Wikipedia →Hilo is the largest settlement in and the county seat of Hawaiʻi County, Hawaii, United States, which encompasses the Island of Hawaiʻi, and is a census-designated place (CDP). The population was 44,186 according to the 2020 census. It is the fourth-largest settlement in the state of Hawaiʻi, the largest settlement in the state outside of Oahu, and the largest settlement in the state outside of the Greater Honolulu Area.
Learn more about your water
Guides and resources related to Papaikou's water quality findings.
Explore water quality across Hawaii
Frequently asked questions
Is Papaikou, HI tap water safe to drink?
Papaikou's water quality earned a grade of A- (89.7/100). The water generally meets EPA standards and is considered safe for consumption. The city ranks #46 out of 66 cities tested in Hawaii.
What contaminants are in Papaikou's water?
Lead was measured at 0.0 ppb (90th percentile). 2 violations are on record.
How is Papaikou'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 Papaikou?
Based on current data, basic filtration should suffice for additional peace of mind.
Where does Papaikou's water come from?
Papaikou's water is sourced from Groundwater. The city has 1 water system serving approximately 2,203 residents.
Is Papaikou's groundwater at risk of contamination?
Papaikou 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 2 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 Papaikou's water compare to other cities?
Papaikou ranks #46 out of 66 cities in Hawaii (better than 30% of state cities) and #2653 out of 15744 cities nationally (83th percentile). The grade of A- reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.
Does Papaikou's small water system affect quality?
Papaikou's system serves approximately 2,203 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 2 violations on record.