Community Water System · PWS AK2260032
Twin Hills Water System
Operator location Twin Hills, Alaska - smaller served population (≤ 999) at 87 people served; 493 SDWIS violations on record from groundwater sources.
- 87
- People served (this PWS)
- 493
- EPA violations (this PWS)
- 57
- Health-based (this PWS)
- Untested
- UCMR5 (this PWS)
Twin Hills Water System standing, high SDWIS violation third
87 people served (SDWIS) - smaller served population (≤ 999). Corpus terciles use 29,740 systems serving 500+ (the sitemap cohort). Health-based share 12% is middle-third health share (≤ 23%).
The verdict
Twin Hills Water System sits in the upper third of the sitemap cohort by violation count (493), so the tables below sample a dense compliance trail rather than a near-clean ledger. Population served is smaller (87; smaller served population (≤ 999)), so each violation row represents a compact service footprint. Health-based share is 12% (middle-third health share (≤ 23%)). No UCMR5 PFAS test appears for this system in this extract.
- 493
- Total EPA violations on record
- 12%
- Health-based (MCL / treatment failure)
- 87
- People served by this PWS (SDWIS)
- N/A
- PFAS compounds detected (UCMR5)
Population ordinals match the sitemap cohort (systems serving 500+, population_served DESC). See methodology · corpus placement.
System Details
- System Type
- Community
- Owner Type
- Native American
- Connections
- 28
- County
- Dillingham Census Area
- School/Daycare
- No
- MCL Violations
- 9
- Monitoring Violations
- 291
- Treatment Tech Violations
- 48
Violation History
Contaminant violations recorded by EPA.
| Contaminant | Category | Count | Latest |
|---|---|---|---|
| Coliform (TCR) | MR | 88 | 2013 |
| Groundwater Rule | TT | 48 | 2020 |
| Nitrate | MR | 20 | 2024 |
| Revised Total Coliform Rule | MON | 12 | 2024 |
| Lead and Copper Rule | MR | 9 | 2021 |
| Coliform (TCR) | MCL | 9 | 2006 |
| Consumer Confidence Rule | Other | 5 | 2021 |
| Mercury | MR | 4 | 1999 |
| p-Dichlorobenzene | MR | 4 | 2004 |
| 1,1,1-Trichloroethane | MR | 4 | 2004 |
| Carbon tetrachloride | MR | 4 | 2004 |
| Trichloroethylene | MR | 4 | 2004 |
| Benzene | MR | 4 | 2004 |
| 1,1-Dichloroethylene | MR | 4 | 2004 |
| 1,2-Dichloroethane | MR | 4 | 2004 |
| HEXACHLOROBENZENE | MR | 3 | 2025 |
| Vinyl chloride | MR | 3 | 2004 |
| Heptachlor epoxide | MR | 3 | 2025 |
| 2,4-D | MR | 3 | 2025 |
| Carbofuran | MR | 3 | 2025 |
| Simazine | MR | 3 | 2025 |
| Heptachlor | MR | 3 | 2025 |
| BHC-GAMMA | MR | 3 | 2025 |
| Atrazine | MR | 3 | 2025 |
| 2,4,5-TP | MR | 3 | 2025 |
| Benzo(a)pyrene | MR | 3 | 2025 |
| ETHYLENE DIBROMIDE | MR | 3 | 2025 |
| Endrin | MR | 3 | 2025 |
| Endothall | MR | 3 | 2025 |
| Di(2-ethylhexyl) phthalate | MR | 3 | 2025 |
Violation Count vs. the National Corpus
Twin Hills Water System has 493 recorded EPA violations, 95% of the 29,740 public water systems serving 500+ people nationwide carry fewer, and 5% carry more. 12% of this system's own violations are health-based (57 of 493), and it ranks unranked by population served among that same cohort.
EPA violations vs. the national water-system corpus
Public water systems serving 500+ people (EPA SDWIS)
493 Higher than most more violations than 95% 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
Population served record for Twin Hills Water System
EPA SDWIS lists 87 people served and 28 connections for this PWS, confirm the service-area footprint on the federal report before comparing to municipal census totals.
Sources: EPA SDWIS
Nationwide peers
493 violations · 87 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.
What to do with Twin Hills Water System
Use this system's EPA-reported record as a starting filter, not a final verdict.
- See how every tracked system in Alaska compares on the same EPA violation measures. Alaska 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.