Maui County Water Quality
Hawaii
According to EPA SDWIS, Maui County, Hawaii hosts 31 community water systems covering about 154,649 people. The same extract lists 7 health-based violation records across 6 systems. Counts are historical EPA registry rows, not a current compliance or drinkability score.
Maui County, Hawaii hosts 31 EPA-regulated community water systems delivering drinking water to approximately 154,649 people. Each system is catalogued in the EPA Safe Drinking Water Information System (SDWIS) under the Safe Drinking Water Act, which mandates monitoring for dozens of regulated contaminants, public notification when standards are exceeded, and the issuance of an annual Consumer Confidence Report.
PlainEnviro's health-based SDWIS extract shows 7 violation records across these active community systems, with 6 systems carrying at least one record. The extract excludes monitoring and reporting violations. The county contains 10 incorporated places where these systems deliver service.
A historical health-based registry row does not establish water delivered today or describe current compliance. For current conditions, request the utility's most recent Consumer Confidence Report or contact the Hawaii drinking water program. Figures shown here reflect only the health-based subset fetched from federal EPA SDWIS.
What water systems serve Maui County?
| System Name | Pop. Served | Violations | Status |
|---|---|---|---|
| WAILUKU | 74,511 | 0 | Clean |
| MAKAWAO | 29,868 | 1 | Health |
| LAHAINA | 20,065 | 1 | Health |
| UPPER KULA | 7,686 | 0 | Clean |
| KAPALUA | 4,200 | 0 | Clean |
| KAUNAKAKAI | 3,702 | 0 | Clean |
| LOWER KULA | 3,522 | 1 | Health |
| HOOLEHUA | 2,400 | 0 | Clean |
| HANA | 1,284 | 0 | Clean |
| HALEAKALA NATIONAL PARK | 1,200 | 0 | Clean |
| UALAPUE | 1,119 | 0 | Clean |
| MAUNALOA-KALUAKOI | 1,000 | 1 | Health |
| HANA WATER SYSTEMS - SOUTH | 816 | 0 | Clean |
| MAHANALUA NUI SUBDIVISON | 606 | 0 | Clean |
| KAWELA PLANTATION | 553 | 0 | Clean |
| KUALAPUU | 500 | 0 | Clean |
| KALAE | 360 | 0 | Clean |
| KEANAE | 270 | 0 | Clean |
| HANA WATER SYSTEMS - NORTH | 160 | 0 | Clean |
| KAHAKULOA WATER CO. | 150 | 1 | Health |
| NAHIKU | 107 | 0 | Clean |
| OLOWALU | 100 | 0 | Clean |
| MAUNAOLU PLANTATION | 100 | 0 | Clean |
| KIPU | 80 | 0 | Clean |
| KULA NANI | 80 | 0 | Clean |
| WEST KUIAHA MEADOWS | 60 | 0 | Clean |
| HONOKOHAU | 42 | 0 | Clean |
| BALDWIN RANCH ESTATES | 32 | 0 | Clean |
| VILLA ROSE | 30 | 2 | Health |
| MAUI HIGHLANDS | 26 | 0 | Clean |
| HAIKU TOWN WATER ASSOCIATION, INC. | 20 | 0 | Clean |
How does Maui County compare in Hawaii?
Of the 5 Hawaii counties with at least one community water system on file, Maui County ranks #2 by number of systems (31).
Either side of it: Hawaii County (36), Honolulu County (20), Kauai County (16)
What are Maui County's health-based records for?
Maui County's health-based violation records carry 4 distinct EPA codes: some name a substance, others the drinking-water rule that was breached. Counts are records on file in the EPA SDWIS extract, not current test results, and a historical record does not establish present water quality.
| Contaminant | Records | Systems |
|---|---|---|
| Surface Water Treatment Rule | 3 | 3 |
| Lead and Copper Rule Revisions | 2 | 1 |
| Tthm | 1 | 1 |
| Lead and Copper Rule | 1 | 1 |
About This Data
Water system data comes from the EPA's Safe Drinking Water Information System (SDWIS). PlainEnviro's violation fetch is restricted upstream to records EPA flags as health-based and then joined to active community water systems. Monitoring and reporting violations are not included.
Figures here are the current EPA SDWIS extract joined to the 31 community water systems whose service area falls in Maui County, ranked against the 5 Hawaii counties with at least one system on file. Data current as of 2026-08-10. Editorial standards, methodology, report an error.
A health-based violation row in this extract is a historical EPA registry entry. It does not describe water delivered today or current compliance status. Many records are later resolved, and public water systems notify customers when required. For current conditions, contact your local water utility or the state drinking water program.
Read our methodology - how this data is sourced, computed, and verified.