Community Water System · PWS NN4900220
Aneth NTUA
Operator location Ft Defiance, Navajo Nation - 38% of 196 violations are health-based (upper-third health share (> 23%)); groundwater source; 1,481 served per SDWIS.
- 1,481
- People served (this PWS)
- 196
- EPA violations (this PWS)
- 74
- Health-based (this PWS)
- Untested
- UCMR5 (this PWS)
Aneth NTUA standing, high SDWIS violation third
38% of 196 recorded violations are health-based - upper-third health share (> 23%). Corpus terciles use 29,740 systems serving 500+ (the sitemap cohort). Health-based share 38% is upper-third health share (> 23%). Population rank #16,131 of 29,740 among systems serving 500+.
The verdict
Aneth NTUA sits in the upper third of the sitemap cohort by violation count (196), so the tables below sample a dense compliance trail rather than a near-clean ledger. Population served is mid-pack at 1,481 (mid served population (≤ 3,309)). Health-based share is 38% - most of this ledger is MCL or treatment-technique exceedance. No UCMR5 PFAS test appears for this system in this extract.
- #16,131 of 29,740
- Population · /systems
- #25 of 82
- Population · NN
- 196
- Total EPA violations on record
- 38%
- Health-based (MCL / treatment failure)
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
- 433
- School/Daycare
- No
- MCL Violations
- 74
- Monitoring Violations
- 97
- Treatment Tech Violations
- 0
Violation History
Contaminant violations recorded by EPA.
| Contaminant | Category | Count | Latest |
|---|---|---|---|
| Arsenic | MCL | 72 | 2024 |
| Arsenic | MR | 28 | 2024 |
| Public Notice | Other | 11 | 2022 |
| Total Haloacetic Acids (HAA5) | MR | 3 | 2020 |
| Stage 2 Disinfectants and Disinfection Byproducts Rule | MR | 3 | 2013 |
| TTHM | MR | 3 | 2020 |
| Combined Uranium | MCL | 2 | 2010 |
| Coliform (TCR) | MR | 2 | 2012 |
| Revised Total Coliform Rule | Other | 2 | 2016 |
| Nitrite | MR | 1 | 2010 |
| BHC-GAMMA | MR | 1 | 2004 |
| Diquat | MR | 1 | 2004 |
| Endothall | MR | 1 | 2004 |
| Di(2-ethylhexyl) adipate | MR | 1 | 2004 |
| Simazine | MR | 1 | 2004 |
| Di(2-ethylhexyl) phthalate | MR | 1 | 2004 |
| Dinoseb | MR | 1 | 2004 |
| Aldicarb | MR | 1 | 2004 |
| Atrazine | MR | 1 | 2004 |
| LASSO | MR | 1 | 2004 |
| 2,3,7,8-TCDD | MR | 1 | 2004 |
| Heptachlor | MR | 1 | 2004 |
| 2,4-D | MR | 1 | 2004 |
| 2,4,5-TP | MR | 1 | 2004 |
| Benzo(a)pyrene | MR | 1 | 2004 |
| Pentachlorophenol | MR | 1 | 2004 |
| cis-1,2-Dichloroethylene | MR | 1 | 2005 |
| Xylenes, Total | MR | 1 | 2005 |
| o-Dichlorobenzene | MR | 1 | 2005 |
| 1,1-Dichloroethylene | MR | 1 | 2005 |
Violation Count vs. the National Corpus
Aneth NTUA has 196 recorded EPA violations, 85% of the 29,740 public water systems serving 500+ people nationwide carry fewer, and 15% carry more. 38% of this system's own violations are health-based (74 of 196), and it ranks #16,131 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)
196 Higher than most more violations than 85% 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 Aneth NTUA
74 health-based rows in the tables above map to MCL or treatment-technique exceedances, verify each contaminant code on the federal SDWIS report for NN4900220.
Sources: EPA SDWIS
Nationwide peers
196 violations · 1,481 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 Aneth NTUA
Use this system's EPA-reported record as a starting filter, not a final verdict.
- See how every tracked system in Navajo Nation compares on the same EPA violation measures. Navajo Nation 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.