Community Water System · PWS NN0403047
Lukachukai NTUA
Operator location Ft Defiance, Navajo Nation - 23% of 80 violations are health-based (upper-third health share (> 23%)); groundwater source; 1,659 served per SDWIS.
- 1,659
- People served (this PWS)
- 80
- EPA violations (this PWS)
- 18
- Health-based (this PWS)
- Untested
- UCMR5 (this PWS)
Lukachukai NTUA standing, high SDWIS violation third
23% of 80 recorded violations are health-based - upper-third health share (> 23%). Corpus terciles use 29,740 systems serving 500+ (the sitemap cohort). Health-based share 23% is upper-third health share (> 23%). Population rank #15,069 of 29,740 among systems serving 500+.
The verdict
Lukachukai NTUA sits in the upper third of the sitemap cohort by violation count (80), so the tables below sample a dense compliance trail rather than a near-clean ledger. Population served is mid-pack at 1,659 (mid served population (≤ 3,309)). Health-based share is 23% - most of this ledger is MCL or treatment-technique exceedance. No UCMR5 PFAS test appears for this system in this extract.
- #15,069 of 29,740
- Population · /systems
- #19 of 82
- Population · NN
- 80
- Total EPA violations on record
- 23%
- 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
- 485
- School/Daycare
- No
- MCL Violations
- 18
- Monitoring Violations
- 39
- Treatment Tech Violations
- 0
Violation History
Contaminant violations recorded by EPA.
| Contaminant | Category | Count | Latest |
|---|---|---|---|
| Arsenic | MCL | 18 | 2012 |
| Coliform (TCR) | MR | 6 | 2012 |
| TTHM | MR | 3 | 2020 |
| Arsenic | MR | 3 | 2012 |
| Total Haloacetic Acids (HAA5) | MR | 3 | 2020 |
| Stage 2 Disinfectants and Disinfection Byproducts Rule | MR | 2 | 2013 |
| Revised Total Coliform Rule | Other | 2 | 2016 |
| Nitrite | MR | 1 | 2010 |
| cis-1,2-Dichloroethylene | MR | 1 | 2005 |
| Xylenes, Total | MR | 1 | 2005 |
| DICHLOROMETHANE | MR | 1 | 2005 |
| o-Dichlorobenzene | MR | 1 | 2005 |
| 1,1-Dichloroethylene | MR | 1 | 2005 |
| 1,1,1-Trichloroethane | MR | 1 | 2005 |
| 1,2-Dichloropropane | MR | 1 | 2005 |
| Trichloroethylene | MR | 1 | 2005 |
| 1,1,2-Trichloroethane | MR | 1 | 2005 |
| Tetrachloroethylene | MR | 1 | 2005 |
| Benzene | MR | 1 | 2005 |
| Toluene | MR | 1 | 2005 |
| 1,2-Dichloroethane | MR | 1 | 2005 |
| 1,2,4-Trichlorobenzene | MR | 1 | 2005 |
| Carbon tetrachloride | MR | 1 | 2005 |
| CHLOROBENZENE | MR | 1 | 2005 |
| Ethylbenzene | MR | 1 | 2005 |
| trans-1,2-Dichloroethylene | MR | 1 | 2005 |
| p-Dichlorobenzene | MR | 1 | 2005 |
| Vinyl chloride | MR | 1 | 2005 |
| Styrene | MR | 1 | 2005 |
Violation Count vs. the National Corpus
Lukachukai NTUA has 80 recorded EPA violations, 68% of the 29,740 public water systems serving 500+ people nationwide carry fewer, and 31% carry more. 23% of this system's own violations are health-based (18 of 80), and it ranks #15,069 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)
80 Around the middle fewer violations than 31% 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 Lukachukai NTUA
18 health-based rows in the tables above map to MCL or treatment-technique exceedances, verify each contaminant code on the federal SDWIS report for NN0403047.
Sources: EPA SDWIS
Nationwide peers
80 violations · 1,659 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 Lukachukai 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.