Community Water System · PWS NN0403015
Oak Springs NTUA (south of Hunters Point)
Operator location Ft Defiance, Navajo Nation - smaller served population (≤ 999) at 390 people served; 44 SDWIS violations on record from groundwater sources.
- 390
- People served (this PWS)
- 44
- EPA violations (this PWS)
- 3
- Health-based (this PWS)
- Untested
- UCMR5 (this PWS)
Oak Springs NTUA (south of Hunters Point) standing, mid SDWIS violation third
390 people served (SDWIS) - smaller served population (≤ 999). Corpus terciles use 29,740 systems serving 500+ (the sitemap cohort). Health-based share 7% is middle-third health share (≤ 23%).
The verdict
Oak Springs NTUA (south of Hunters Point) lands in the middle third by violation volume (44), large enough for peer comparisons without matching the fleet's heaviest ledgers. Population served is smaller (390; smaller served population (≤ 999)), so each violation row represents a compact service footprint. Health-based share is 7% (middle-third health share (≤ 23%)). No UCMR5 PFAS test appears for this system in this extract.
- 44
- Total EPA violations on record
- 7%
- Health-based (MCL / treatment failure)
- 390
- 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
- 114
- School/Daycare
- No
- MCL Violations
- 3
- Monitoring Violations
- 32
- Treatment Tech Violations
- 0
Violation History
Contaminant violations recorded by EPA.
| Contaminant | Category | Count | Latest |
|---|---|---|---|
| Coliform (TCR) | MR | 6 | 2015 |
| Stage 2 Disinfectants and Disinfection Byproducts Rule | MR | 3 | 2013 |
| Coliform (TCR) | MCL | 3 | 2015 |
| Revised Total Coliform Rule | Other | 2 | 2016 |
| Xylenes, Total | MR | 1 | 2005 |
| o-Dichlorobenzene | MR | 1 | 2005 |
| Vinyl chloride | MR | 1 | 2005 |
| trans-1,2-Dichloroethylene | MR | 1 | 2005 |
| 1,2-Dichloroethane | MR | 1 | 2005 |
| Carbon tetrachloride | MR | 1 | 2005 |
| 1,2-Dichloropropane | MR | 1 | 2005 |
| 1,1,2-Trichloroethane | MR | 1 | 2005 |
| CHLOROBENZENE | MR | 1 | 2005 |
| Benzene | MR | 1 | 2005 |
| Styrene | MR | 1 | 2005 |
| Gross Alpha, Excl. Radon and U | MR | 1 | 2004 |
| 1,1-Dichloroethylene | MR | 1 | 2005 |
| 1,2,4-Trichlorobenzene | MR | 1 | 2005 |
| 1,1,1-Trichloroethane | MR | 1 | 2005 |
| Toluene | MR | 1 | 2005 |
| p-Dichlorobenzene | MR | 1 | 2005 |
| Trichloroethylene | MR | 1 | 2005 |
| Nitrite | MR | 1 | 2010 |
| cis-1,2-Dichloroethylene | MR | 1 | 2005 |
| Tetrachloroethylene | MR | 1 | 2005 |
| Ethylbenzene | MR | 1 | 2005 |
| DICHLOROMETHANE | MR | 1 | 2005 |
Violation Count vs. the National Corpus
Oak Springs NTUA (south of Hunters Point) has 44 recorded EPA violations, 53% of the 29,740 public water systems serving 500+ people nationwide carry fewer, and 46% carry more. 7% of this system's own violations are health-based (3 of 44), 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)
44 Around the middle fewer violations than 46% 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 Oak Springs NTUA (south of Hunters Point)
EPA SDWIS lists 390 people served and 114 connections for this PWS, confirm the service-area footprint on the federal report before comparing to municipal census totals.
Sources: EPA SDWIS
Nationwide peers
44 violations · 390 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.
What to do with Oak Springs 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.