Hawaii Water Quality Report
66 cities tested · Average grade: A · 1.5M people served
Live Water Alerts for Hawaii →Latest water news in Hawaii
Recent reporting on Hawaii drinking water — boil-water advisories, regulatory action, and infrastructure events.
Hawaii water quality overview
Hawaii's drinking water quality is excellent overall, with an average score of 91.6 out of 100 across 66 cities tested. The median score is 92.6, serving a total population of 1,501,217 residents. 100% of cities earned an A or B grade, indicating broadly strong water quality infrastructure across the state. PFAS "forever chemicals" were detected in 2 of 66 cities tested (3%). All detected levels remain within current EPA limits. The state relies on a mix of water sources: 60 cities use groundwater while 6 draw from surface water such as rivers, lakes, and reservoirs.
Issues to watch in Hawaii
Explore contaminants in Hawaii
More contaminants tested in Hawaii
Top industrial water polluters in Hawaii
Industrial polluters nearby
The 10 facilities reporting the most pounds released to surface water in Hawaii, 2023.
Total reported releases to surface water: 512,764 lbs
| Facility | Top chemical | To surface water (lbs/yr) |
|---|---|---|
JOINT BASE PEARL HARBOR-HICKAM HAWAII JBPHH, HI96860 | Nitrate compounds (water dissociable; reportable only when in aqueous solution) | 390,000 |
US MARINE CORPS BASE HAWAII KANEOHE BAY MCBH KANEOHE BAY, HI96863 | Nitrate compounds (water dissociable; reportable only when in aqueous solution) | 122,728 |
HFFC AIRPORT FUEL FARM HONOLULU, HI96819 | Biphenyl | 30 |
HAWAIIAN ELECTRIC CO INC KAHE GENERATING STATION KAPOLEI, HI96707 | Lead And Lead Compounds | 4 |
HAWAIIAN ELECTRIC CO INC WAIAU GENERATING STATION PEARL CITY, HI96782 | Lead And Lead Compounds | 2 |
+ 1 more facility
Source: EPA Toxic Release Inventory (TRI) 2023
How Hawaii cities scored
Best Cities
Worst Cities
Water quality across Hawaii
Each dot is a city, colored by its water quality grade. Size reflects population served. Click any city to view its full water report.
66 cities in Hawaii
| # | City | Grade | Score | Population | Violations |
|---|---|---|---|---|---|
| 1 | Olaa-Mt.View | A+ | 100 | 6K | 0 |
| 2 | Haina | A+ | 100 | 5K | 0 |
| 3 | Kilauea (Dow) | A+ | 100 | 3K | 1 |
| 4 | Downtown Honolulu | A+ | 99.3 | 3K | 9 |
| 5 | Sunset Beach | A+ | 99 | 5K | 0 |
| 6 | Waiohinu-Naalehu | A+ | 98.5 | 3K | 0 |
| 7 | Mililani Bws | A+ | 97.5 | 51K | 14 |
| 8 | Kapalua (Dho) | A+ | 97.3 | 4K | 6 |
| 9 | Lalamilo | A+ | 97 | 2K | 1 |
| 10 | Paauilo | A+ | 97 | 716 | 0 |
| 11 | Mahanalua Nui | A+ | 97 | 606 | 0 |
| 12 | Kawela | A+ | 97 | 553 | 1 |
| 13 | Haena-Wainiha | A+ | 96.9 | 833 | 2 |
| 14 | Waikoloa (Dho) | A+ | 96.7 | 12K | 6 |
| 15 | Anahola | A+ | 96.2 | 3K | 6 |
| 16 | Kaunakakai | A+ | 96.1 | 4K | 12 |
| 17 | Mokuleia | A+ | 96.1 | 2K | 8 |
| 18 | Waipio | A+ | 95.8 | 12K | 0 |
| 19 | Pearl Harbor | A | 94.8 | 65K | 11 |
| 20 | Kekaha (Dow) | A | 94.5 | 6K | 9 |
| 21 | Ualapue | A | 94.3 | 1K | 9 |
| 22 | Keola Hana-Hotel Dho | A | 94.3 | 816 | 8 |
| 23 | Wahiawa | A | 94 | 8K | 37 |
| 24 | Moanalua | A | 94 | 6K | 9 |
| 25 | Kaumakani | A | 93.8 | 1K | 10 |
| 26 | Hana | A | 93.7 | 1K | 13 |
| 27 | Salt Lake | A | 93.5 | 6K | 6 |
| 28 | Lihue-Kapaa | A | 93.3 | 35K | 10 |
| 29 | Hawaiian Shores Dho | A | 93.2 | 5K | 4 |
| 30 | Hoolehua | A | 93.2 | 2K | 13 |
| 31 | Honomu | A | 93 | 645 | 0 |
| 32 | Waipahu-Ewa-Waianae | A | 92.8 | 223K | 9 |
| 33 | Princeville (Dho) | A | 92.7 | 7K | 2 |
| 34 | Laie | A | 92.6 | 6K | 2 |
| 35 | Kualapuu | A | 92.3 | 500 | 22 |
| 36 | Schofield Barracks | A | 91.8 | 45K | 15 |
| 37 | Hilo | A | 91.7 | 39K | 49 |
| 38 | Kaanapali (Dho) | A | 91.7 | 8K | 7 |
| 39 | Lanai | A | 91.5 | 3K | 46 |
| 40 | Wailuku | A | 91.4 | 75K | 19 |
| 41 | Honolulu-Windward-Pearlharbor | A | 91.1 | 631K | 44 |
| 42 | Hvnp (Dho) | A | 90.5 | 4K | 4 |
| 43 | Maunaloa, Molokai | A | 90.1 | 1K | 41 |
| 44 | South Kona | A- | 89.7 | 7K | 1 |
| 45 | Kapalama | A- | 89.7 | 4K | 1 |
| 46 | Papaikou | A- | 89.7 | 2K | 2 |
| 47 | Pahoa | A- | 89.7 | 2K | 2 |
| 48 | Hanalei (Dow) | A- | 89.7 | 674 | 2 |
| 49 | Pmrf Housing (Dho) | A- | 89.6 | 1K | 2 |
| 50 | Hanapepe-Eleele (Dow) | A- | 89.5 | 6K | 4 |
| 51 | Kalaheo | A- | 89 | 13K | 3 |
| 52 | Kaneohe | A- | 88.3 | 16K | 7 |
| 53 | North Kona | A- | 88.2 | 30K | 2 |
| 54 | Pahala | A- | 86.7 | 1K | 1 |
| 55 | Laupahoehoe | A- | 86.7 | 1K | 1 |
| 56 | Kahuku | A- | 85.9 | 3K | 1 |
| 57 | North Kohala | A- | 85.7 | 5K | 1 |
| 58 | Waialua-Haleiwa | B+ | 84.2 | 11K | 8 |
| 59 | Honolulu | B+ | 83.3 | 23K | 8 |
| 60 | Makawao | B+ | 83 | 31K | 101 |
| 61 | Kohala Joint Venture | B+ | 82.7 | 850 | 1 |
| 62 | Pepeekeo | B+ | 82.4 | 2K | 2 |
| 63 | South Kohala | B+ | 80.4 | 10K | 97 |
| 64 | Kona | B | 79.8 | 3K | 17 |
| 65 | Lahaina | B | 77.1 | 20K | 146 |
| 66 | Kula | B- | 74.5 | 12K | 139 |
Browse Hawaii by ZIP code
Look up water quality by ZIP code to find the systems serving your area.
View all Hawaii ZIP codes →Frequently asked questions about Hawaii's water
Is Hawaii's tap water safe to drink?
Hawaii's water quality varies by city. The statewide average grade is A (91.6/100). 100% of cities scored an A or B, while 0% received a D or F. Check your specific city for detailed results.
Which Hawaii cities have the best water quality?
The top-rated cities are Olaa-Mt.View (A+), Haina (A+), Kilauea (Dow) (A+). These cities scored highest based on violation history, lead levels, PFAS contamination, and regulatory compliance.
Which Hawaii cities have the worst water quality?
The lowest-rated cities are Kula (B-), Lahaina (B), Kona (B). We recommend residents in these areas consider water filtration and review their city's specific contaminant data.
How many Hawaii cities have PFAS in their water?
2 out of 66 cities tested positive for PFAS "forever chemicals" (3%). All detected levels are currently within EPA limits.