Water Quality in Honolulu, HI: No Violations — Grade A
Grade A · Score 85/100 · 5 water systems · Updated 2026-05-03
Honolulu's water meets all EPA standards with no health-based violations.
Data: EPA Safe Drinking Water Information System (SDWIS) Last verified: 2026-05-03
Across all available EPA tracking data for Honolulu, HI, the record has remained clean — 5 public water systems on file, zero violations recorded, and no enforcement proceedings initiated at any point in the federal dataset.
Water Quality Map: Honolulu, HI
Each dot represents a ZIP code. Color indicates water quality grade. Tap a dot for details.
Water Quality by ZIP Code in Honolulu
Water quality varies across Honolulu's 41 ZIP codes. Check your specific ZIP for detailed contaminant data.
| ZIP Code | Grade | Score | Violations | Health | |
|---|---|---|---|---|---|
| 96821 | B | 72 | 0 | 0 | View report → |
| 96815 | B | 77 | 0 | 0 | View report → |
| 96816 | B | 77 | 0 | 0 | View report → |
| 96819 | B | 77 | 0 | 0 | View report → |
| 96822 | B | 77 | 0 | 0 | View report → |
| 96825 | B | 77 | 0 | 0 | View report → |
| 96826 | B | 77 | 0 | 0 | View report → |
| 96813 | B | 82 | 0 | 0 | View report → |
| 96817 | B | 82 | 0 | 0 | View report → |
| 96801 | A | 87 | 0 | 0 | View report → |
| 96803 | A | 87 | 0 | 0 | View report → |
| 96804 | A | 87 | 0 | 0 | View report → |
| 96810 | A | 87 | 0 | 0 | View report → |
| 96811 | A | 87 | 0 | 0 | View report → |
| 96814 | A | 87 | 0 | 0 | View report → |
Water Quality Overview
Honolulu, Hawaii receives a water quality grade of A with an overall score of 85 out of 100, based on EPA compliance data from the Safe Drinking Water Information System (SDWIS).
No EPA violations have been recorded for the 5 water systems serving Honolulu. This is a positive indicator, though it does not guarantee the absence of all contaminants — some substances (like PFAS) are not yet fully regulated.
What Grade A Means
A grade of A indicates excellent compliance with EPA drinking water standards. Honolulu's water systems have maintained strong performance in both contaminant monitoring and regulatory compliance.
Lead Levels
Lead testing data for Honolulu is currently being collected. The EPA requires all community water systems to test for lead under the Lead and Copper Rule.
With 75% of homes built before 1986, Honolulu has a higher-than-average risk of lead from older plumbing. Lead solder was banned in 1986, and homes built before this date may have lead in pipes, solder joints, or fixtures.
Water Systems Serving Honolulu
Honolulu is served by 5 community water systems regulated under the Safe Drinking Water Act. These systems collectively serve approximately 934,305 people across 41 ZIP codes.
Each water system is identified by a Public Water System ID (PWSID) and is required to:
- Test for over 90 regulated contaminants on a regular schedule
- Report results to the EPA and state regulators
- Issue an annual Consumer Confidence Report (CCR) to all customers
- Take corrective action when violations occur
The EPA has taken 123 enforcement actions against water systems serving Honolulu. Enforcement actions range from informal compliance assistance to formal orders and penalties.
How to Check Your Water in Honolulu
Enter your ZIP code on ZipCheckup to see your specific water system data, including contaminant levels, violation history, and safety scores
Request your CCR — your water utility must provide an annual Consumer Confidence Report with detailed test results for all monitored contaminants
Get a home test — certified kits cost $20–$50 and test for lead, bacteria, and common contaminants. Professional lab tests ($150–$400) cover a broader panel
Consider filtration — NSF-certified filters can remove specific contaminants. Reverse osmosis removes the broadest range; activated carbon is effective for chlorine and many organics
Check for advisories — monitor your local utility website and local news for boil water advisories or system alerts
EPA Enforcement History
The EPA and state regulators have taken 3 enforcement actions against water systems serving Honolulu. Recent actions:
| Date | Action Type |
|---|---|
| 2024-12-07 | State Informal Action |
| 2024-12-07 | State Order Extension |
| 2024-12-06 | State Informal Action |
Enforcement actions range from informal compliance assistance to formal orders and penalties. The most recent action was on 2024-12-07.
Honolulu vs. Nearby Hawaii Cities
How Honolulu's water quality compares to similar cities in Hawaii:
| City | Grade | Violations | Systems | Population |
|---|---|---|---|---|
| Honolulu | A | 0 | 5 | 934,305 |
| J B P H H | C | 0 | 2 | 631,833 |
| Fort Shafter | C | 0 | 1 | 631,389 |
| Waimanalo | C | 0 | 1 | 631,389 |
Water Quality by ZIP Code in Honolulu
Water quality varies across Honolulu's ZIP codes. The table below shows the worst-scoring and best-scoring areas:
| ZIP Code | Score | Grade | Violations | Health-Based |
|---|---|---|---|---|
| 96821 | 72 | B | 0 | 0 |
| 96815 | 77 | B | 0 | 0 |
| 96816 | 77 | B | 0 | 0 |
| 96819 | 77 | B | 0 | 0 |
| 96822 | 77 | B | 0 | 0 |
| 96825 | 77 | B | 0 | 0 |
| 96826 | 77 | B | 0 | 0 |
| 96813 | 82 | B | 0 | 0 |
| 96817 | 82 | B | 0 | 0 |
| 96801 | 87 | A | 0 | 0 |
| 96850 | 88 | A | 0 | 0 |
| 96849 | 88 | A | 0 | 0 |
| 96848 | 88 | A | 0 | 0 |
| 96847 | 88 | A | 0 | 0 |
| 96846 | 88 | A | 0 | 0 |
Common Questions About Honolulu Water
These are the most common questions residents search for about water quality in Honolulu, Hawaii:
Is Honolulu water hard or soft? Water hardness varies by source. Honolulu's 5 water systems use multiple sources. Check your ZIP code report for specific hardness data.
Can I drink Honolulu tap water? Honolulu's water receives a grade of A (85/100). No health-based violations have been recorded, but home testing is always recommended.
What is the best water filter for Honolulu? A NSF/ANSI 53-certified filter for lead removal is a good general choice. See our Water Filter Matcher for personalized recommendations.
Honolulu vs. Hawaii Average
Understanding how Honolulu compares to the broader Hawaii average helps contextualize your local water quality. Factors like water source, treatment methods, and infrastructure age all contribute to differences between cities in the same state.
To see how individual neighborhoods compare, check the ZIP code reports below — water quality can vary significantly even within Honolulu.
ZIP Codes in Honolulu
Honolulu spans 41 ZIP codes. Each ZIP code has its own water quality profile based on the specific water system serving that area. Check each ZIP code for detailed contaminant data, violation history, and system information.
Data Sources
- Water quality: EPA Safe Drinking Water Information System (SDWIS)
- Lead/copper: EPA Lead and Copper Rule sampling data
- Radon: EPA Map of Radon Zones
- Enforcement: EPA ECHO database
- Filter recommendations: NSF/ANSI certified products
Updated daily.
Frequently Asked Questions
Your Water is Safe — Here's How to Keep It That Way
Grade A is excellent news. Here's what proactive homeowners do to maintain water quality:
Annual Water Testing
EPA recommends annual testing even with clean water. Home test kits: $20-$50. Catches changes before they become problems.
Maintenance Filtration
A basic carbon filter removes chlorine taste and catches emerging contaminants like PFAS that aren't yet fully regulated.
Plumbing Check
Even safe city water picks up lead from home pipes. If your home was built before 1986, a one-time pipe inspection is recommended.