Wailuku Water Quality
Hawaii
According to EPA SDWIS, Wailuku, Hawaii is served by 18 community water systems covering about 142,982 people. The same extract lists 6 health-based violation records, most recently coded 5200 in 2024. Counts are historical EPA registry rows, not a current compliance or drinkability score.
Drinking water in Wailuku, Hawaii is delivered through 18 EPA-regulated community water systems serving an estimated 142,982 people. Each system is tracked in the EPA Safe Drinking Water Information System (SDWIS) under the Safe Drinking Water Act, which requires testing for regulated contaminants, consumer notification of violations, and publication of an annual Consumer Confidence Report.
PlainEnviro's health-based SDWIS extract shows 6 violation records across the 18 active community systems shown here. Monitoring and reporting records are not present in the extract. The records carry 3 distinct EPA contaminant codes: LEAD AND COPPER RULE REVISIONS, Surface Water Treatment Rule, Lead and Copper Rule.
A past EPA health-based registry row does not describe water delivered today or current compliance status; utilities notify customers and remediate under state primacy oversight when required. For current water-quality status and treatment practices, review your local utility's most recent Consumer Confidence Report or contact the Hawaii drinking water program. All records above reflect federal EPA SDWIS data and are not independently verified against state databases.
Community Water Systems
| 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 |
| KAUNAKAKAI | 3,702 | 0 | Clean |
| LOWER KULA | 3,522 | 1 | Health |
| HANA | 1,284 | 0 | Clean |
| UALAPUE | 1,119 | 0 | Clean |
| KALAE | 360 | 0 | Clean |
| KEANAE | 270 | 0 | Clean |
| KAHAKULOA WATER CO. | 150 | 1 | Health |
| NAHIKU | 107 | 0 | Clean |
| MAUNAOLU PLANTATION | 100 | 0 | Clean |
| KULA NANI | 80 | 0 | Clean |
| WEST KUIAHA MEADOWS | 60 | 0 | Clean |
| HONOKOHAU | 42 | 0 | Clean |
| VILLA ROSE | 30 | 2 | Health |
| MAUI HIGHLANDS | 26 | 0 | Clean |
Does this city have health-based water violations?
These health-based records can represent Maximum Contaminant Level (MCL), Treatment Technique (TT), or Maximum Residual Disinfectant Level (MRDL) categories. A historical record does not establish that water is currently unsafe.
| Water system | Contaminant | Begin Date |
|---|---|---|
| VILLA ROSE | LEAD AND COPPER RULE REVISIONS | 2024-10-17 |
| VILLA ROSE | LEAD AND COPPER RULE REVISIONS | 2024-10-17 |
| MAKAWAO | Surface Water Treatment Rule | 2020-05-01 |
| KAHAKULOA WATER CO. | Lead and Copper Rule | 2009-01-01 |
| LOWER KULA | Surface Water Treatment Rule | 1997-01-01 |
| LAHAINA | Surface Water Treatment Rule | 1997-01-01 |
Frequently Asked Questions
What does EPA SDWIS list for drinking water in Wailuku, Hawaii? ▼
How many water violations does Wailuku have in this EPA extract? ▼
What contaminants were found in Wailuku water? ▼
How many water systems serve Wailuku? ▼
Where does Wailuku get its drinking water? ▼
How does Wailuku compare in Hawaii?
Of the 33 Hawaii places with at least one community water system on file, Wailuku ranks #2 by number of systems (18).
About This Data
Figures here are the current EPA SDWIS extract joined to the 18 community water systems whose service area lists Wailuku, ranked against the 33 Hawaii places with at least one system on file. Data current as of 2026-08-10.
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.
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.
TRI facility data comes from the EPA Toxic Release Inventory. Facilities shown are those that self-report to the TRI program. PlainEnviro presents this data without advocacy framing.
Read our methodology - how this data is sourced, computed, and verified.