Public water system · HI0000371

Active

Poamoho

At a glance

Poamoho (PWSID HI0000371) is an active community water system in Honolulu County, Hawaii. It reports serving 25 people through 15 service connections. Its primary water source is groundwater, and EPA lists it as privately owned. EPA's records list 8 violations for this system; 4 are health-based, and the most recent began in July 2015.

Dataset updated October 2026 . Source: EPA SDWIS/ECHO public records.

Population served

Service connections

Primary source

Groundwater

System type

CWS

Community water system

System record

PWSIDHI0000371

System typeCommunity water system

Activity statusActive

Population served25

Service connections15

Primary water sourceGroundwater

Owner typePrivate

Primacy agencyHI state drinking water program

City servedWahiawa

StateHawaii

ZIP—

CountyHonolulu County

How does Poamoho compare with other water systems in Honolulu County?

By EPA's size categories, Poamoho is a very small system (500 people or fewer). Honolulu County has 38 active public water systems. Its population served is well below the county average of 29,687 people per system, and accounts for less than 0.1% of the 1,128,119 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 Poamoho 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 Poamoho?

EPA lists Poamoho as privately owned. 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. 16 of the 38 active systems in Honolulu County (42%) are also privately owned.

Does Poamoho have drinking water violations?

EPA's records list 8 violations for this system; 4 are health-based, and the most recent began in July 2015. The violations listed here began between August 2011 and July 2015. By type: 4 contaminant level above the legal limit and 4 monitoring and reporting. The contaminant or rule involved most often is Total coliform bacteria (TCR) (5 of them). EPA lists 8 as resolved. 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.

Began	Violation	Contaminant or rule	Health-based	Status
2015-07-01	Contaminant level above the legal limitMaximum Contaminant Level Violation, Acute (TCR) · code 21	Total coliform bacteria (TCR)code 3100	Yes	Resolved
2015-07-01	Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22	Total coliform bacteria (TCR)code 3100	Yes	Resolved
2015-07-01	Monitoring and reportingMonitoring, Repeat Minor (TCR) · code 26	Total coliform bacteria (TCR)code 3100	No	Resolved
2015-01-01	Monitoring and reportingMonitoring and Reporting (DBP) · code 27	Haloacetic acids (HAA5)code 2456	No	Resolved
2015-01-01	Monitoring and reportingMonitoring and Reporting (DBP) · code 27	Total trihalomethanes (TTHM)code 2950	No	Resolved
2014-05-01	Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22	Total coliform bacteria (TCR)code 3100	Yes	Resolved
2012-01-01	Monitoring and reportingFollow-up Or Routine LCR Tap M/R · code 52	Lead and Copper Rulecode 5000	No	Resolved
2011-08-01	Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22	Total coliform bacteria (TCR)code 3100	Yes	Resolved

All 8 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.

Poamoho: frequently asked questions

Who runs Poamoho?

Poamoho (PWSID HI0000371) is a community water system privately owned. It is regulated by the HI state drinking water program.

How many people does Poamoho serve?

Poamoho reports serving 25 people through 15 service connections in Honolulu County, Hawaii.

Where does Poamoho 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 Poamoho have any drinking water violations?

EPA's records list 8 violations for this system; 4 are health-based, and the most recent began in July 2015. 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 Poamoho'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 8 violations for this system; 4 are health-based, and the most recent began in July 2015. For current results, consult the system's annual water quality report, EPA ECHO, or the HI state drinking water program.

Where can I find Poamoho's water quality report?

As a community water system, Poamoho 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 Honolulu County

Water system	County	Population served	Type	Source
Hnl-Windward-Pearl Harbor	Honolulu	631,389	Community	Groundwater
Waipahu-Ewa-Waianae	Honolulu	217,479	Community	Groundwater
Joint Base Pearl Harbor-Hickam	Honolulu	65,230	Community	Groundwater
Mililani	Honolulu	50,573	Community	Groundwater
Schofield Barracks	Honolulu	37,920	Community	Groundwater
Wahiawa	Honolulu	23,348	Community	Groundwater

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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, “Poamoho, PWSID HI0000371, Hawaii”, https://aquacensus.com/water-systems/hawaii/poamoho-hi0000371 (data as of October 1, 2026).