Community Water System · PWS HI0000231
Maunaloa-Kaluakoi
Operator location Maunaloa, Hawaii - upper-third violation load (> 74 violations) with 140 EPA violations; groundwater source; 1,000 served (PWS-level, not municipal population).
- 1,000
- People served (this PWS) Middle third of systems
- 140
- EPA violations (this PWS) Upper third of systems
- 31
- Health-based (this PWS) Middle third by health-based share
- Untested
- UCMR5 (this PWS) No UCMR5 result
Maunaloa-Kaluakoi standing, high SDWIS violation third
140 EPA SDWIS violations on record - upper-third violation load (> 74 violations). Corpus terciles use 29,740 systems serving 500+ (the sitemap cohort). Health-based share 22% is middle-third health share (≤ 23%). Population rank #19,546 of 29,740 among systems serving 500+.
The verdict
Maunaloa-Kaluakoi sits in the upper third of the sitemap cohort by violation count (140), so the tables below sample a dense compliance trail rather than a near-clean ledger. Population served is mid-pack at 1,000 (mid served population (≤ 3,309)). Health-based share is 22% (middle-third health share (≤ 23%)). No UCMR5 PFAS test appears for this system in this extract.
- #19,546 of 29,740
- Population · /systems
- #67 of 81
- Population · HI
- 140
- Total EPA violations on record
- 22%
- Health-based (MCL / treatment failure)
Population ordinals match the sitemap cohort (systems serving 500+, population_served DESC). See methodology · corpus placement.
Based on EPA SDWIS violation history and UCMR5 PFAS testing only, not water taste, odor, infrastructure age, or contaminants outside the federally tracked set.
System Details
- System Type
- Community
- Owner Type
- Private
- Connections
- 358
- County
- Maui
- School/Daycare
- No
- MCL Violations
- 10
- Monitoring Violations
- 18
- Treatment Tech Violations
- 21
Violation History
Contaminant violations recorded by EPA.
| Contaminant | Category | Count | Latest |
|---|---|---|---|
| Coliform (Pre-TCR) | Other | 25 | 1990 |
| Surface Water Treatment Rule | TT | 18 | 2007 |
| TTHM | MCL | 10 | 2016 |
| Surface Water Treatment Rule | MR | 6 | 1993 |
| Lead and Copper Rule | MR | 5 | 2022 |
| CARBON, TOTAL | TT | 3 | 2005 |
| CYANIDE | MR | 3 | 2008 |
| Coliform (TCR) | MR | 3 | 1998 |
| Gross Alpha, Excl. Radon and U | MR | 1 | 2000 |
Violation Count vs. the National Corpus
Maunaloa-Kaluakoi has 140 recorded EPA violations, 80% of the 29,740 public water systems serving 500+ people nationwide carry fewer, and 20% carry more. 22% of this system's own violations are health-based (31 of 140), and it ranks #19,546 of 29,740 by population served among that same cohort.
EPA violations vs. the national water-system corpus
Public water systems serving 500+ people (EPA SDWIS)
140 Higher than most more violations than 80% of 29,740 water systems
the national water-system corpus, bucketed by value
Each bar is a band; taller bars hold more water systems. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count and share, and where it sits relative to this entry.
Source EPA SDWIS · 2026-05-15
How many violations vs. how serious, among peer systems
Maunaloa-Kaluakoi plotted against 29 peer public water systems (500+ people served), by total violation count (x) and the share of those violations that are health-based (y). The crosshair sits at this sample's own median on each axis. A high violation count does not automatically mean a serious record: most monitoring and reporting violations are minor, not health-based.
Violation volume vs. health-based share
SDWIS compliance record for Maunaloa-Kaluakoi
140 violations on record for HI0000231; use EPA SDWIS to confirm return-to-compliance dates and monitoring categories.
Sources: EPA SDWIS
Nationwide peers
140 violations · 1,000 served: nearest cross-state SDWIS matches.
Cross-state systems with comparable violation load
Nearest cross-state community systems (500+ served) by total SDWIS violations on record.
Cross-state systems near this population served
Nearest cross-state systems by EPA SDWIS population_served (same 500+ sitemap gate).
What to do with Maunaloa-Kaluakoi
Use this system's EPA-reported record as a starting filter, not a final verdict.
- See how every tracked system in Hawaii compares on the same EPA violation measures. Hawaii systems
- Check whether PFAS was detected at this system under UCMR5 testing. PFAS guide
- Find and compare another public water system by name or PWSID. Search systems
EPA SDWIS and UCMR5 figures are informational only, not a substitute for a certified lab test of your own tap water.
Every figure on PlainWater is rendered directly from EPA SDWIS drinking-water data, no number is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error.