Community Water System · PWS NN4903071
Todahaidekani NTUA
Operator location Ft Defiance, Navajo Nation - smaller served population (≤ 999) at 301 people served; 140 SDWIS violations on record from surface water sources.
- 301
- People served (this PWS)
- 140
- EPA violations (this PWS)
- 31
- Health-based (this PWS)
- Untested
- UCMR5 (this PWS)
Todahaidekani NTUA standing, high SDWIS violation third
301 people served (SDWIS) - smaller served population (≤ 999). Corpus terciles use 29,740 systems serving 500+ (the sitemap cohort). Health-based share 22% is middle-third health share (≤ 23%).
The verdict
Todahaidekani NTUA 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 smaller (301; smaller served population (≤ 999)), so each violation row represents a compact service footprint. Health-based share is 22% (middle-third health share (≤ 23%)). No UCMR5 PFAS test appears for this system in this extract.
- 140
- Total EPA violations on record
- 22%
- Health-based (MCL / treatment failure)
- 301
- 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
- 88
- School/Daycare
- No
- MCL Violations
- 31
- Monitoring Violations
- 82
- Treatment Tech Violations
- 0
Violation History
Contaminant violations recorded by EPA.
| Contaminant | Category | Count | Latest |
|---|---|---|---|
| Arsenic | MCL | 31 | 2020 |
| Public Notice | Other | 8 | 2020 |
| Coliform (TCR) | MR | 6 | 2012 |
| Arsenic | MR | 3 | 2022 |
| Stage 2 Disinfectants and Disinfection Byproducts Rule | MR | 3 | 2013 |
| Glyphosate | MR | 2 | 2008 |
| Gross Alpha, Excl. Radon and U | MR | 2 | 2005 |
| Revised Total Coliform Rule | Other | 2 | 2016 |
| Endothall | MR | 2 | 2008 |
| 2,3,7,8-TCDD | MR | 2 | 2008 |
| Total Polychlorinated Biphenyls (PCB) | MR | 2 | 2008 |
| Diquat | MR | 2 | 2008 |
| Fluoride | MR | 1 | 2008 |
| Nitrite | MR | 1 | 2010 |
| Selenium | MR | 1 | 2008 |
| Antimony, Total | MR | 1 | 2008 |
| Beryllium, Total | MR | 1 | 2008 |
| Endrin | MR | 1 | 2008 |
| Dalapon | MR | 1 | 2008 |
| Di(2-ethylhexyl) adipate | MR | 1 | 2008 |
| Simazine | MR | 1 | 2008 |
| Di(2-ethylhexyl) phthalate | MR | 1 | 2008 |
| Picloram | MR | 1 | 2008 |
| Hexachlorocyclopentadiene | MR | 1 | 2008 |
| Atrazine | MR | 1 | 2008 |
| LASSO | MR | 1 | 2008 |
| Heptachlor epoxide | MR | 1 | 2008 |
| 2,4-D | MR | 1 | 2008 |
| HEXACHLOROBENZENE | MR | 1 | 2008 |
| Pentachlorophenol | MR | 1 | 2008 |
Violation Count vs. the National Corpus
Todahaidekani NTUA 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 unranked 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
Population served record for Todahaidekani NTUA
EPA SDWIS lists 301 people served and 88 connections for this PWS, confirm the service-area footprint on the federal report before comparing to municipal census totals.
Sources: EPA SDWIS
Nationwide peers
140 violations · 301 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 Todahaidekani 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.