Community Water System · PWS NN0400181
Tsehootsooi Middle School
Operator location Fort Defiance, Navajo Nation - smaller served population (≤ 999) at 875 people served; 309 SDWIS violations on record from groundwater sources.
- 875
- People served (this PWS)
- 309
- EPA violations (this PWS)
- 2
- Health-based (this PWS)
- Untested
- UCMR5 (this PWS)
Tsehootsooi Middle School standing, high SDWIS violation third
875 people served (SDWIS) - smaller served population (≤ 999). Corpus terciles use 29,740 systems serving 500+ (the sitemap cohort). Health-based share 1% is middle-third health share (≤ 23%). Population rank #21,479 of 29,740 among systems serving 500+.
The verdict
Tsehootsooi Middle School sits in the upper third of the sitemap cohort by violation count (309), so the tables below sample a dense compliance trail rather than a near-clean ledger. Population served is smaller (875; smaller served population (≤ 999)), so each violation row represents a compact service footprint. Health-based share is 1% (middle-third health share (≤ 23%)). No UCMR5 PFAS test appears for this system in this extract.
- #21,479 of 29,740
- Population · /systems
- #54 of 82
- Population · NN
- 309
- Total EPA violations on record
- 1%
- 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
- Local
- Connections
- 116
- School/Daycare
- Yes
- MCL Violations
- 2
- Monitoring Violations
- 205
- Treatment Tech Violations
- 0
Violation History
Contaminant violations recorded by EPA.
| Contaminant | Category | Count | Latest |
|---|---|---|---|
| Coliform (TCR) | MR | 69 | 2016 |
| Revised Total Coliform Rule | MON | 37 | 2025 |
| Consumer Confidence Rule | Other | 24 | 2024 |
| Revised Total Coliform Rule | RPT | 18 | 2025 |
| Total Haloacetic Acids (HAA5) | MR | 11 | 2020 |
| TTHM | MR | 11 | 2020 |
| Public Notice | Other | 9 | 2025 |
| Lead and Copper Rule | MR | 7 | 2024 |
| Stage 2 Disinfectants and Disinfection Byproducts Rule | MR | 3 | 2013 |
| Revised Total Coliform Rule | Other | 2 | 2016 |
| Coliform (TCR) | MCL | 2 | 2008 |
| CHLOROBENZENE | MR | 1 | 1996 |
| Methoxychlor | MR | 1 | 1996 |
| Styrene | MR | 1 | 1996 |
| Nitrate | MR | 1 | 1996 |
| LASSO | MR | 1 | 1996 |
| Toluene | MR | 1 | 1996 |
| 1,2-DIBROMO-3-CHLOROPROPANE | MR | 1 | 1996 |
| Hexachlorocyclopentadiene | MR | 1 | 1996 |
| ETHYLENE DIBROMIDE | MR | 1 | 1996 |
| Ethylbenzene | MR | 1 | 1996 |
| Endothall | MR | 1 | 1996 |
| Selenium | MR | 1 | 1996 |
| Chlordane | MR | 1 | 1996 |
| Vinyl chloride | MR | 1 | 1996 |
| Barium | MR | 1 | 1996 |
| Carbofuran | MR | 1 | 1996 |
| 1,1,2-Trichloroethane | MR | 1 | 1996 |
| 1,1-Dichloroethylene | MR | 1 | 1996 |
| Cadmium | MR | 1 | 1996 |
Violation Count vs. the National Corpus
Tsehootsooi Middle School has 309 recorded EPA violations, 91% of the 29,740 public water systems serving 500+ people nationwide carry fewer, and 9% carry more. 1% of this system's own violations are health-based (2 of 309), and it ranks #21,479 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)
309 Higher than most more violations than 91% 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 Tsehootsooi Middle School
EPA SDWIS lists 875 people served and 116 connections for this PWS, confirm the service-area footprint on the federal report before comparing to municipal census totals.
Sources: EPA SDWIS
Nationwide peers
309 violations · 875 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 with smaller service footprints
Nearest cross-state systems by EPA SDWIS population_served (same 500+ sitemap gate).
What to do with Tsehootsooi Middle School
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.