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Community Water System · PWS 104101102

Simnasho Schoolie

Operator location Warm Springs, EPA Region 10 — Tribal Water Systems - smaller served population (≤ 999) at 350 people served; 335 SDWIS violations on record from groundwater sources.

350
People served (this PWS)
335
EPA violations (this PWS)
53
Health-based (this PWS)
Untested
UCMR5 (this PWS)
Follow published updates (RSS)

Simnasho Schoolie standing, high SDWIS violation third

350 people served (SDWIS) - smaller served population (≤ 999). Corpus terciles use 29,740 systems serving 500+ (the sitemap cohort). Health-based share 16% is middle-third health share (≤ 23%).

The verdict

Simnasho Schoolie sits in the upper third of the sitemap cohort by violation count (335), so the tables below sample a dense compliance trail rather than a near-clean ledger. Population served is smaller (350; smaller served population (≤ 999)), so each violation row represents a compact service footprint. Health-based share is 16% (middle-third health share (≤ 23%)). No UCMR5 PFAS test appears for this system in this extract.

335
Total EPA violations on record
16%
Health-based (MCL / treatment failure)
350
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
83
School/Daycare
No
MCL Violations
41
Monitoring Violations
254
Treatment Tech Violations
12

Violation History

Contaminant violations recorded by EPA.

Contaminant Category Count Latest
Arsenic MCL 40 2014
Consumer Confidence Rule Other 12 2023
Public Notice Other 12 2025
Arsenic MR 11 2014
Groundwater Rule TT 11 2025
2,3,7,8-TCDD MR 7 2017
Nitrate MR 7 2024
Coliform (TCR) MR 6 2012
Benzene MR 5 2015
Atrazine MR 5 2015
OXAMYL MR 4 2015
Diquat MR 4 2015
Glyphosate MR 4 2015
Di(2-ethylhexyl) adipate MR 4 2015
Simazine MR 4 2015
Di(2-ethylhexyl) phthalate MR 4 2015
Dinoseb MR 4 2015
Endothall MR 4 2015
Carbofuran MR 4 2015
LASSO MR 4 2015
Heptachlor MR 4 2015
2,4-D MR 4 2015
1,2,4-Trichlorobenzene MR 4 2015
cis-1,2-Dichloroethylene MR 4 2015
Xylenes, Total MR 4 2015
DICHLOROMETHANE MR 4 2015
p-Dichlorobenzene MR 4 2015
Carbon tetrachloride MR 4 2015
1,2-Dichloropropane MR 4 2015
Trichloroethylene MR 4 2015

Violation Count vs. the National Corpus

Simnasho Schoolie has 335 recorded EPA violations, 92% of the 29,740 public water systems serving 500+ people nationwide carry fewer, and 8% carry more. 16% of this system's own violations are health-based (53 of 335), 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)

335 Higher than most more violations than 92% 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 Simnasho Schoolie

EPA SDWIS lists 350 people served and 83 connections for this PWS, confirm the service-area footprint on the federal report before comparing to municipal census totals.

Sources: EPA SDWIS

Nationwide peers

335 violations · 350 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.

4 peers

What to do with Simnasho Schoolie

Use this system's EPA-reported record as a starting filter, not a final verdict.

EPA SDWIS and UCMR5 figures are informational only, not a substitute for a certified lab test of your own tap water.

Data sourced from EPA SDWIS and UCMR5 PFAS monitoring data. See our methodology for details. Retrieved and formatted by PlainWater