We found 68 public water systems in Honolulu county (ordered by population size).
| Name | Areas served | Population served | Contaminant count | Violation count |
|---|---|---|---|---|
| Hnl-windward-pearl Harbor | Honolulu-windward-pearlharbor | 630,266 | 511 | 42 |
| Waipahu-ewa-waianae | Waipahu-ewa-waianae | 210,683 | 190 | 5 |
| Joint Base Pearl Harbor-hickam | Pearl Harbor | 65,230 | 58 | 7 |
| Mililani | Mililani Bws | 50,420 | 34 | 14 |
| Board Of Water Supply | Pearl Harbor | 47,500 | 0 | 0 |
| Schofield Barracks | Schofield Barracks | 40,850 | 20 | 7 |
| Wahiawa | County of Honolulu | 23,257 | 28 | 0 |
| Marine Corps Base Hawaii | Kaneohe | 16,300 | 16 | 3 |
| Waipio Heights | Waipio | 11,870 | 28 | 0 |
| Waialua-haleiwa | Waialua-haleiwa | 9,867 | 18 | 0 |
| Fort Shafter | County of Honolulu | 7,268 | 0 | 5 |
| Aliamanu | Salt Lake | 6,630 | 0 | 4 |
| Nctams Eastpac | Wahiawa | 6,005 | 0 | 1 |
| Tripler Army Medical Cntr | Moanalua | 5,992 | 0 | 8 |
| Laie Water Company | Laie | 5,577 | 0 | 1 |
| Barbers Point | Waipahu-ewa-waianae | 5,256 | 0 | 2 |
| Waialee-sunset Beach | Sunset Beach | 4,928 | 0 | 0 |
| Punahou School | Manoa | 4,000 | 0 | 3 |
| Kamehameha Schools | Kapalama | 4,000 | 0 | 0 |
| The Queen's Medical Center | Downtown Honolulu | 3,400 | 0 | 9 |
| Waianae Rec | Waianae | 3,318 | 0 | 0 |
| Hawaii State Hospital | Kaneohe | 3,000 | 0 | 0 |
| Sheraton Hotels | County of Honolulu | 2,830 | 0 | 8 |
| Kahuku | Kahuku | 2,757 | 0 | 1 |
| Dillingham Airfield | Mokuleia | 1,800 | 0 | 8 |
| Radford Terrace | Radford Terrace | 1,500 | 0 | 0 |
| Dole Fresh Fruit | Canning Op, Honolulu | 1,200 | 0 | 0 |
| Ewa Villages | Ewa | 1,144 | 0 | 0 |
| Kahuku Housing Corporation | County of Honolulu | 1,000 | 0 | 0 |
| Visitor Center | Haleakala Np, Visitor Center | 1,000 | 0 | 0 |
| The Queen's Medical Center West Oahu | Kunia | 800 | 0 | 0 |
| Kunia Village | Wahiawa | 650 | 0 | 26 |
| Camp Stover | Wahiawa | 595 | 0 | 0 |
| Camp Erdman Ymca | County of Honolulu | 500 | 0 | 0 |
| Waiawa Correctional Facility | Waipahu | 444 | 0 | 82 |
| Hawaii Country Club | Nuuanu | 400 | 0 | 4 |
| Mass Transit Lines | County of Honolulu | 400 | 0 | 0 |
| Waimano Ridge | Pearlridge | 400 | 0 | 9 |
| Waialua Sugar Pump 2 | Waialua-haleiwa | 400 | 0 | 4 |
| Wheeler | Wheeler | 389 | 0 | 0 |
| National Park Service | Kapalaoa | 350 | 0 | 0 |
| Pacific Club | Honolulu | 300 | 0 | 0 |
| Makaha Valley | County of Honolulu | 300 | 0 | 0 |
| National Park Service | Hosmer | 300 | 0 | 0 |
| Waiahole | Kahana Valley | 300 | 0 | 1 |
| Kapalama | Kapalama | 258 | 0 | 0 |
| National Park Service | Holua | 250 | 0 | 0 |
| Waialua Sugar Pump 3 | Waialua | 240 | 0 | 0 |
| Oahu Sugar Waipahu | Waipahu | 212 | 0 | 0 |
| National Park Service | Paliku | 200 | 0 | 0 |
| Mokuleia Associates | County of Honolulu | 150 | 0 | 0 |
| Navmag Lualualei | Waianae | 114 | 0 | 0 |
| Kahuku | Kahuku | 100 | 0 | 0 |
| Fort Kamehameha | Fort Kam | 100 | 0 | 0 |
| Malaekahana | Kakuku, Malaekahana | 100 | 0 | 0 |
| Dillingham Ranch | Waialua-haleiwa | 100 | 0 | 0 |
| Mililani Memorial Park | Mililani Bws | 100 | 0 | 0 |
| Kahuku Air Base | Kahuku Air Base | 75 | 0 | 0 |
| C&h Sugar | County of Honolulu | 75 | 0 | 0 |
| Waialua Sugar Co. | County of Honolulu | 60 | 0 | 0 |
| Palehua Solar Observatory | Makakilo | 50 | 0 | 0 |
| Woodlands At Nuuanu | Honolulu | 48 | 0 | 0 |
| St Stephen's Diocesan Ctr | Kaneohe | 45 | 0 | 0 |
| Kipapa Acres C.p.r. | County of Honolulu | 43 | 0 | 0 |
| Kahana Valley State Park | Kahana | 42 | 0 | 0 |
| Poamoho | Wahiawa | 25 | 0 | 0 |
| Gerald Kremkow | Waikii Ranch | 25 | 0 | 0 |
| Navmag Waikele | Waikele | 10 | 0 | 0 |