Community Water System · PWS NN0403055
Teec Nos Pos NTUA
Operator location Ft Defiance, Navajo Nation - smaller served population (≤ 999) at 752 people served; 64 SDWIS violations on record from surface water sources.
- 752
- People served (this PWS) Smaller third of systems
- 64
- EPA violations (this PWS) Middle third of systems
- 4
- Health-based (this PWS) Middle third by health-based share
- Untested
- UCMR5 (this PWS) No UCMR5 result
Teec Nos Pos NTUA standing, mid SDWIS violation third
752 people served (SDWIS) - smaller served population (≤ 999). Corpus terciles use 29,740 systems serving 500+ (the sitemap cohort). Health-based share 6% is middle-third health share (≤ 23%). Population rank #23,291 of 29,740 among systems serving 500+.
The verdict
Teec Nos Pos NTUA lands in the middle third by violation volume (64), large enough for peer comparisons without matching the fleet's heaviest ledgers. Population served is smaller (752; smaller served population (≤ 999)), so each violation row represents a compact service footprint. Health-based share is 6% (middle-third health share (≤ 23%)). No UCMR5 PFAS test appears for this system in this extract.
- #23,291 of 29,740
- Population · /systems
- #65 of 82
- Population · NN
- 64
- Total EPA violations on record
- 6%
- 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
- Native American
- Connections
- 220
- School/Daycare
- No
- MCL Violations
- 4
- Monitoring Violations
- 44
- Treatment Tech Violations
- 0
Violation History
Contaminant violations recorded by EPA.
| Contaminant | Category | Count | Latest |
|---|---|---|---|
| Coliform (TCR) | MR | 5 | 2012 |
| Fluoride | MR | 4 | 2011 |
| Combined Radium (-226 and -228) | MCL | 3 | 2013 |
| Stage 2 Disinfectants and Disinfection Byproducts Rule | MR | 3 | 2013 |
| Revised Total Coliform Rule | Other | 2 | 2016 |
| Combined Uranium | MCL | 1 | 2010 |
| Arsenic | MR | 1 | 2008 |
| Nitrite | MR | 1 | 2010 |
| Selenium | MR | 1 | 2008 |
| Thallium, Total | MR | 1 | 2008 |
| 1,2,4-Trichlorobenzene | MR | 1 | 2005 |
| cis-1,2-Dichloroethylene | MR | 1 | 2005 |
| Xylenes, Total | MR | 1 | 2005 |
| DICHLOROMETHANE | MR | 1 | 2005 |
| o-Dichlorobenzene | MR | 1 | 2005 |
| p-Dichlorobenzene | MR | 1 | 2005 |
| Vinyl chloride | MR | 1 | 2005 |
| 1,1-Dichloroethylene | MR | 1 | 2005 |
| trans-1,2-Dichloroethylene | MR | 1 | 2005 |
| 1,2-Dichloroethane | MR | 1 | 2005 |
| Carbon tetrachloride | MR | 1 | 2005 |
| Trichloroethylene | MR | 1 | 2005 |
| Tetrachloroethylene | MR | 1 | 2005 |
| Toluene | MR | 1 | 2005 |
| CHLOROBENZENE | MR | 1 | 2005 |
| 1,2-Dichloropropane | MR | 1 | 2005 |
| Benzene | MR | 1 | 2005 |
| 1,1,2-Trichloroethane | MR | 1 | 2005 |
| 1,1,1-Trichloroethane | MR | 1 | 2005 |
| Antimony, Total | MR | 1 | 2008 |
Violation Count vs. the National Corpus
Teec Nos Pos NTUA has 64 recorded EPA violations, 63% of the 29,740 public water systems serving 500+ people nationwide carry fewer, and 37% carry more. 6% of this system's own violations are health-based (4 of 64), and it ranks #23,291 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)
64 Around the middle fewer violations than 37% 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
Teec Nos Pos NTUA 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
Population served record for Teec Nos Pos NTUA
EPA SDWIS lists 752 people served and 220 connections for this PWS, confirm the service-area footprint on the federal report before comparing to municipal census totals.
Sources: EPA SDWIS
Nationwide peers
64 violations · 752 served: nearest cross-state SDWIS matches.
Cross-state systems near this violation count
Nearest cross-state community systems (500+ served) by total SDWIS violations on record.
Cross-state systems with smaller service footprints
Nearest cross-state systems by EPA SDWIS population_served (same 500+ sitemap gate).
What to do with Teec Nos Pos 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.
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.