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Community Water System · PWS OR4100372

Hermiston, City Of

Operator location Hermiston, Oregon - UCMR5 detected 5 PFAS compounds (upper-third PFAS panel (> 4 compounds)) on this PWS; SDWIS lists 168 violations and 20,000 people served.

20,000
People served (this PWS)
168
EPA violations (this PWS)
9
Health-based (this PWS)
5 PFAS
UCMR5 (this PWS)
Follow published updates (RSS)

Hermiston, City Of standing, high SDWIS violation third

UCMR5 detected 5 PFAS compounds - upper-third PFAS panel (> 4 compounds). Corpus terciles use 29,740 systems serving 500+ (the sitemap cohort). Health-based share 5% is middle-third health share (≤ 23%). UCMR5: upper-third PFAS panel (> 4 compounds). Population rank #2,719 of 29,740 among systems serving 500+.

The verdict

Hermiston, City Of sits in the upper third of the sitemap cohort by violation count (168), so the tables below sample a dense compliance trail rather than a near-clean ledger. Population served is large (20,000; larger served population (> 3,309)), so household exposure scale sits behind the violation mix. Health-based share is 5% (middle-third health share (≤ 23%)). UCMR5 detected 5 PFAS compounds (upper-third PFAS panel (> 4 compounds)).

#2,719 of 29,740
Population · /systems
#37 of 373
Population · OR
168
Total EPA violations on record
5%
Health-based (MCL / treatment failure)

Population ordinals match the sitemap cohort (systems serving 500+, population_served DESC). See methodology · corpus placement.

PFAS Detected

5 PFAS "forever chemicals" detected in testing under EPA's UCMR5 monitoring program.

System Details

System Type
Community
Owner Type
Local
Connections
5,979
County
Umatilla
School/Daycare
No
MCL Violations
7
Monitoring Violations
157
Treatment Tech Violations
2

Violation History

Contaminant violations recorded by EPA.

Contaminant Category Count Latest
Coliform (TCR) MR 10 1993
TTHM MR 10 2016
Total Haloacetic Acids (HAA5) MR 10 2016
Surface Water Treatment Rule MR 9 2013
Coliform (TCR) MCL 7 1998
COLIPHAGE MR 6 2022
Interim Enhanced Surface Water Treatment Rule MR 5 2013
Arsenic MR 3 2009
Endrin MR 2 2002
BHC-GAMMA MR 2 2002
Toxaphene MR 2 2002
Dalapon MR 2 2002
Diquat MR 2 2002
Endothall MR 2 2002
Glyphosate MR 2 2002
Di(2-ethylhexyl) adipate MR 2 2002
OXAMYL MR 2 2002
Simazine MR 2 2002
Picloram MR 2 2002
Dinoseb MR 2 2002
Hexachlorocyclopentadiene MR 2 2002
Atrazine MR 2 2002
LASSO MR 2 2002
Heptachlor MR 2 2002
Heptachlor epoxide MR 2 2002
2,4,5-TP MR 2 2002
HEXACHLOROBENZENE MR 2 2002
Total Polychlorinated Biphenyls (PCB) MR 2 2002
1,2-DIBROMO-3-CHLOROPROPANE MR 2 2002
ETHYLENE DIBROMIDE MR 2 2002

Violation Count vs. the National Corpus

Hermiston, City Of has 168 recorded EPA violations, 83% of the 29,740 public water systems serving 500+ people nationwide carry fewer, and 17% carry more. 5% of this system's own violations are health-based (9 of 168), and it ranks #2,719 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)

168 Higher than most more violations than 83% 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

PFAS Testing Results (UCMR5)

Results from EPA's Fifth Unregulated Contaminant Monitoring Rule. 17 of 316 samples detected PFAS.

Contaminant Date Result MRL Status
PFTA 9/11/2023 <8.00 ppt 8.00 ppt Not Detected
NMeFOSAA 9/11/2023 <6.00 ppt 6.00 ppt Not Detected
NEtFOSAA 9/11/2023 <5.00 ppt 5.00 ppt Not Detected
PFTrDA 9/11/2023 <7.00 ppt 7.00 ppt Not Detected
PFTA 6/20/2023 <8.00 ppt 8.00 ppt Not Detected
PFTrDA 6/20/2023 <7.00 ppt 7.00 ppt Not Detected
NEtFOSAA 6/20/2023 <5.00 ppt 5.00 ppt Not Detected
NMeFOSAA 6/20/2023 <6.00 ppt 6.00 ppt Not Detected
PFPeS 6/20/2023 <4.00 ppt 4.00 ppt Not Detected
PFPeA 6/20/2023 <3.00 ppt 3.00 ppt Not Detected
4:2 FTS 6/20/2023 <3.00 ppt 3.00 ppt Not Detected
PFHpS 6/20/2023 <3.00 ppt 3.00 ppt Not Detected
PFMBA 6/20/2023 <3.00 ppt 3.00 ppt Not Detected
PFDA 6/20/2023 <3.00 ppt 3.00 ppt Not Detected
PFMPA 6/20/2023 <4.00 ppt 4.00 ppt Not Detected
8:2 FTS 6/20/2023 <5.00 ppt 5.00 ppt Not Detected
NFDHA 6/20/2023 <20.00 ppt 20.00 ppt Not Detected
PFBS 6/20/2023 3.40 ppt 3.00 ppt Detected
PFEESA 6/20/2023 <3.00 ppt 3.00 ppt Not Detected
6:2 FTS 6/20/2023 <5.00 ppt 5.00 ppt Not Detected
PFDoA 6/20/2023 <3.00 ppt 3.00 ppt Not Detected
PFTA 6/20/2023 <8.00 ppt 8.00 ppt Not Detected
PFTrDA 6/20/2023 <7.00 ppt 7.00 ppt Not Detected
NEtFOSAA 6/20/2023 <5.00 ppt 5.00 ppt Not Detected
PFHpA 6/20/2023 <3.00 ppt 3.00 ppt Not Detected
PFHxS 6/20/2023 8.00 ppt 3.00 ppt Detected
9Cl-PF3ONS 6/20/2023 <2.00 ppt 2.00 ppt Not Detected
PFBA 6/20/2023 <5.00 ppt 5.00 ppt Not Detected
HFPO-DA 6/20/2023 <5.00 ppt 5.00 ppt Not Detected
NMeFOSAA 6/20/2023 <6.00 ppt 6.00 ppt Not Detected
ADONA 6/20/2023 <3.00 ppt 3.00 ppt Not Detected
PFNA 6/20/2023 <4.00 ppt 4.00 ppt Not Detected
11Cl-PF3OUdS 6/20/2023 <5.00 ppt 5.00 ppt Not Detected
PFUnA 6/20/2023 <2.00 ppt 2.00 ppt Not Detected
PFHxA 6/20/2023 <3.00 ppt 3.00 ppt Not Detected
PFOA 6/20/2023 <4.00 ppt 4.00 ppt Not Detected
PFOS 6/20/2023 6.00 ppt 4.00 ppt Detected
8:2 FTS 6/20/2023 <5.00 ppt 5.00 ppt Not Detected
NEtFOSAA 6/20/2023 <5.00 ppt 5.00 ppt Not Detected
NMeFOSAA 6/20/2023 <6.00 ppt 6.00 ppt Not Detected
PFBS 6/20/2023 10.00 ppt 3.00 ppt Detected
PFHpA 6/20/2023 <3.00 ppt 3.00 ppt Not Detected
PFHxS 6/20/2023 8.40 ppt 3.00 ppt Detected
11Cl-PF3OUdS 6/20/2023 <5.00 ppt 5.00 ppt Not Detected
PFNA 6/20/2023 <4.00 ppt 4.00 ppt Not Detected
PFOS 6/20/2023 7.80 ppt 4.00 ppt Detected
ADONA 6/20/2023 <3.00 ppt 3.00 ppt Not Detected
PFBA 6/20/2023 <5.00 ppt 5.00 ppt Not Detected
PFTrDA 6/20/2023 <7.00 ppt 7.00 ppt Not Detected
4:2 FTS 6/20/2023 <3.00 ppt 3.00 ppt Not Detected

UCMR5 PFAS record for Hermiston, City Of

Open EPA SDWIS federal reports for PWS OR4100372 to cross-check UCMR5 detections and violation codes; state primacy agencies enforce the Safe Drinking Water Act locally.

Sources: EPA SDWIS

Nationwide peers

168 violations · 20,000 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

Cross-state systems with similar served population

Nearest cross-state systems by EPA SDWIS population_served (same 500+ sitemap gate).

4 peers

What to do with Hermiston, City Of

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

  • See how every tracked system in Oregon compares on the same EPA violation measures. Oregon 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.

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