Community Water System · PWS AK2120216
Thorne Bay, City Of
Operator location Thorne Bay, Alaska - 41% of 794 violations are health-based (upper-third health share (> 23%)); surface water source; 470 served per SDWIS.
- 470
- People served (this PWS)
- 794
- EPA violations (this PWS)
- 324
- Health-based (this PWS)
- Untested
- UCMR5 (this PWS)
Thorne Bay, City Of standing, high SDWIS violation third
41% of 794 recorded violations are health-based - upper-third health share (> 23%). Corpus terciles use 29,740 systems serving 500+ (the sitemap cohort). Health-based share 41% is upper-third health share (> 23%).
The verdict
Thorne Bay, City Of sits in the upper third of the sitemap cohort by violation count (794), so the tables below sample a dense compliance trail rather than a near-clean ledger. Population served is smaller (470; smaller served population (≤ 999)), so each violation row represents a compact service footprint. Health-based share is 41% - most of this ledger is MCL or treatment-technique exceedance. No UCMR5 PFAS test appears for this system in this extract.
- 794
- Total EPA violations on record
- 41%
- Health-based (MCL / treatment failure)
- 470
- 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
- 251
- School/Daycare
- No
- MCL Violations
- 294
- Monitoring Violations
- 304
- Treatment Tech Violations
- 30
Violation History
Contaminant violations recorded by EPA.
| Contaminant | Category | Count | Latest |
|---|---|---|---|
| TTHM | MCL | 148 | 2020 |
| Total Haloacetic Acids (HAA5) | MCL | 146 | 2021 |
| Interim Enhanced Surface Water Treatment Rule | MR | 77 | 2025 |
| Surface Water Treatment Rule | MR | 23 | 2025 |
| Surface Water Treatment Rule | TT | 22 | 2011 |
| Total Haloacetic Acids (HAA5) | MR | 15 | 2025 |
| TTHM | MR | 15 | 2025 |
| Lead and Copper Rule | MR | 10 | 2025 |
| Interim Enhanced Surface Water Treatment Rule | TT | 8 | 2012 |
| Nitrate | MR | 6 | 2024 |
| Coliform (TCR) | MR | 5 | 2015 |
| Chlorine | MR | 5 | 2015 |
| p-Dichlorobenzene | MR | 5 | 2023 |
| 1,1-Dichloroethylene | MR | 5 | 2023 |
| trans-1,2-Dichloroethylene | MR | 5 | 2023 |
| 1,2-Dichloroethane | MR | 5 | 2023 |
| 1,1,1-Trichloroethane | MR | 5 | 2023 |
| Tetrachloroethylene | MR | 5 | 2023 |
| CHLOROBENZENE | MR | 5 | 2023 |
| Benzene | MR | 5 | 2023 |
| Toluene | MR | 5 | 2023 |
| cis-1,2-Dichloroethylene | MR | 5 | 2023 |
| Consumer Confidence Rule | Other | 5 | 2018 |
| 1,2,4-Trichlorobenzene | MR | 5 | 2023 |
| Xylenes, Total | MR | 5 | 2023 |
| DICHLOROMETHANE | MR | 5 | 2023 |
| Vinyl chloride | MR | 5 | 2023 |
| 1,2-Dichloropropane | MR | 5 | 2023 |
| Trichloroethylene | MR | 5 | 2023 |
| 1,1,2-Trichloroethane | MR | 5 | 2023 |
Violation Count vs. the National Corpus
Thorne Bay, City Of has 794 recorded EPA violations, 98% of the 29,740 public water systems serving 500+ people nationwide carry fewer, and 2% carry more. 41% of this system's own violations are health-based (324 of 794), 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)
794 Higher than most more violations than 98% 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
Health-based violations on Thorne Bay, City Of
324 health-based rows in the tables above map to MCL or treatment-technique exceedances, verify each contaminant code on the federal SDWIS report for AK2120216.
Sources: EPA SDWIS
Nationwide peers
794 violations · 470 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 Thorne Bay, City Of
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.