Public water system · HI0000220
ActiveNahiku
At a glance
Nahiku (PWSID HI0000220) is an active community water system in Maui County, Hawaii. It reports serving 107 people through 43 service connections. Its primary water source is groundwater, and EPA lists it as owned by a local government. EPA's records list 11 violations for this system; 1 is health-based, and the most recent began in January 2008.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
107
Service connections
43
Primary source
GW
Groundwater
System type
CWS
Community water system
System record
How does Nahiku compare with other water systems in Maui County?
By EPA's size categories, Nahiku is a very small system (500 people or fewer). Maui County has 39 active public water systems. Its population served is well below the county average of 4,338 people per system, and accounts for less than 0.1% of the 169,182 people reported by systems filed under the county. Across Hawaii, the 136 active systems average 11,181 people each. Nationally, the average active community water system reports serving 6,703 people, so Nahiku is well below that figure.
What does “community water system” mean?
A community water system serves at least 15 connections used by year-round residents, or regularly serves at least 25 year-round residents. Homes, apartments and mobile-home parks are served by these. Hawaii has 119 active community water systems, 88% of the state's 136 active systems. Groundwater means the system draws its water from wells or springs fed by underground aquifers. 112 Hawaii systems (82%) list groundwater as their primary source.
Who owns and regulates Nahiku?
EPA lists Nahiku as owned by a local government. The HI state drinking water program is its primacy agency, the regulator with primary enforcement responsibility for the system under the Safe Drinking Water Act. 12 of the 39 active systems in Maui County (31%) are also owned by a local government.
Does Nahiku have drinking water violations?
EPA's records list 11 violations for this system; 1 is health-based, and the most recent began in January 2008. The violations listed here began between June 1981 and January 2008. By type: 7 monitoring and reporting, 3 public notice, recordkeeping or other and 1 contaminant level above the legal limit. The contaminant or rule involved most often is Total coliform bacteria (pre-TCR) (3 of them). EPA lists 7 as resolved and 4 as archived. Resolved means at least one resolving action is on record: the system returned to compliance, the rule no longer applies, or no further action was needed. Archived means the violation was not marked resolved but is more than five years past the end of the noncompliance period, so it no longer counts toward current compliance status.
| Began | Violation | Contaminant or rule | Health-based | Status |
|---|---|---|---|---|
| 2008-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | 2,3,7,8-TCDD (dioxin)code 2063 | No | Resolved |
| 2008-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Diquatcode 2032 | No | Resolved |
| 2008-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Benzo(a)pyrenecode 2306 | No | Resolved |
| 2008-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Cyanidecode 1024 | No | Resolved |
| 2008-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Endothallcode 2033 | No | Resolved |
| 2008-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Di(2-ethylhexyl) adipatecode 2035 | No | Resolved |
| 2008-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Di(2-ethylhexyl) phthalatecode 2039 | No | Resolved |
| 1993-02-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | Archived |
| 1984-10-01 | Public notice, recordkeeping or otherNotification, Public · code 06 | Total coliform bacteria (pre-TCR)code 3000 | No | Archived |
| 1981-09-30 | Public notice, recordkeeping or otherNotification, Public · code 06 | Total coliform bacteria (pre-TCR)code 3000 | No | Archived |
| 1981-06-30 | Public notice, recordkeeping or otherNotification, Public · code 06 | Total coliform bacteria (pre-TCR)code 3000 | No | Archived |
All 11 violations in EPA's records, newest first.Labels and codes come from EPA's SDWIS reference tables. A monitoring or reporting violation means a required test or report was missed or late; it does not by itself mean a contaminant was found. "Health-based" marks violations of a legal limit or required treatment.
Nahiku: frequently asked questions
Who runs Nahiku?
Nahiku (PWSID HI0000220) is a community water system owned by a local government. It is regulated by the HI state drinking water program.
How many people does Nahiku serve?
Nahiku reports serving 107 people through 43 service connections in Maui County, Hawaii.
Where does Nahiku get its water?
EPA SDWIS lists this system's primary water source as groundwater. Groundwater means the system draws its water from wells or springs fed by underground aquifers.
Does Nahiku have any drinking water violations?
EPA's records list 11 violations for this system; 1 is health-based, and the most recent began in January 2008. A monitoring or reporting violation means a required test or report was missed or late; it does not by itself mean a contaminant was found.
Is Nahiku's water safe to drink?
AquaCensus shows EPA compliance records, not current water test results, so it cannot say whether the water is safe at a given moment. EPA's records list 11 violations for this system; 1 is health-based, and the most recent began in January 2008. For current results, consult the system's annual water quality report, EPA ECHO, or the HI state drinking water program.
Where can I find Nahiku's water quality report?
As a community water system, Nahiku must deliver an annual water quality report, called a Consumer Confidence Report, to its customers by July 1 each year, covering the previous calendar year. The system can provide a copy on request.
Other water systems in Maui County
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About this data
Source: U.S. EPA Safe Drinking Water Information System (SDWIS) and SDWA violation records, via EPA ECHO, as published October 1, 2026 — AquaCensus refreshes it quarterly. See the methodology for how records are matched, cleaned and scored.
Cite as: AquaCensus, “Nahiku, PWSID HI0000220, Hawaii”, https://aquacensus.com/water-systems/hawaii/nahiku-hi0000220 (data as of October 1, 2026).