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Community Water System · PWS OK1021220

Stillwater Utilities Authority

Operator location Stillwater, Oklahoma - 50% of 160 violations are health-based (upper-third health share (> 23%)); surface water source; 53,000 served per SDWIS.

53,000
People served (this PWS)
160
EPA violations (this PWS)
80
Health-based (this PWS)
5 PFAS
UCMR5 (this PWS)
Follow published updates (RSS)

Stillwater Utilities Authority standing, high SDWIS violation third

50% of 160 recorded violations are health-based - upper-third health share (> 23%). Corpus terciles use 29,740 systems serving 500+ (the sitemap cohort). Health-based share 50% is upper-third health share (> 23%). UCMR5: upper-third PFAS panel (> 4 compounds). Population rank #1,014 of 29,740 among systems serving 500+.

The verdict

Stillwater Utilities Authority sits in the upper third of the sitemap cohort by violation count (160), so the tables below sample a dense compliance trail rather than a near-clean ledger. Population served is large (53,000; larger served population (> 3,309)), so household exposure scale sits behind the violation mix. Health-based share is 50% - most of this ledger is MCL or treatment-technique exceedance. UCMR5 detected 5 PFAS compounds (upper-third PFAS panel (> 4 compounds)).

#1,014 of 29,740
Population · /systems
#9 of 558
Population · OK
160
Total EPA violations on record
50%
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
17,348
County
Payne
School/Daycare
No
MCL Violations
19
Monitoring Violations
58
Treatment Tech Violations
61

Violation History

Contaminant violations recorded by EPA.

Contaminant Category Count Latest
Bromate MR 31 2017
CARBON, TOTAL TT 26 2022
Coliform (TCR) MCL 19 2010
Interim Enhanced Surface Water Treatment Rule TT 18 2018
Surface Water Treatment Rule TT 17 2023
CARBON, TOTAL MR 17 2017
Coliform (TCR) MR 7 2005
Nitrate-Nitrite MR 3 2016

Violation Count vs. the National Corpus

Stillwater Utilities Authority has 160 recorded EPA violations, 82% of the 29,740 public water systems serving 500+ people nationwide carry fewer, and 18% carry more. 50% of this system's own violations are health-based (80 of 160), and it ranks #1,014 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)

160 Higher than most more violations than 82% 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. 14 of 116 samples detected PFAS.

Contaminant Date Result MRL Status
PFHpA 9/3/2024 <3.00 ppt 3.00 ppt Not Detected
PFHxS 9/3/2024 4.10 ppt 3.00 ppt Detected
PFNA 9/3/2024 <4.00 ppt 4.00 ppt Not Detected
PFOS 9/3/2024 6.30 ppt 4.00 ppt Detected
6:2 FTS 9/3/2024 <5.00 ppt 5.00 ppt Not Detected
11Cl-PF3OUdS 9/3/2024 <5.00 ppt 5.00 ppt Not Detected
PFBS 9/3/2024 <3.00 ppt 3.00 ppt Not Detected
NFDHA 9/3/2024 <20.00 ppt 20.00 ppt Not Detected
PFOA 9/3/2024 <4.00 ppt 4.00 ppt Not Detected
PFDA 9/3/2024 <3.00 ppt 3.00 ppt Not Detected
PFDoA 9/3/2024 <3.00 ppt 3.00 ppt Not Detected
PFHxA 9/3/2024 3.20 ppt 3.00 ppt Detected
PFUnA 9/3/2024 <2.00 ppt 2.00 ppt Not Detected
9Cl-PF3ONS 9/3/2024 <2.00 ppt 2.00 ppt Not Detected
ADONA 9/3/2024 <3.00 ppt 3.00 ppt Not Detected
NEtFOSAA 9/3/2024 <5.00 ppt 5.00 ppt Not Detected
PFBA 9/3/2024 <5.00 ppt 5.00 ppt Not Detected
PFTrDA 9/3/2024 <7.00 ppt 7.00 ppt Not Detected
4:2 FTS 9/3/2024 <3.00 ppt 3.00 ppt Not Detected
8:2 FTS 9/3/2024 <5.00 ppt 5.00 ppt Not Detected
PFMPA 9/3/2024 <4.00 ppt 4.00 ppt Not Detected
PFPeA 9/3/2024 <3.00 ppt 3.00 ppt Not Detected
PFMBA 9/3/2024 <3.00 ppt 3.00 ppt Not Detected
PFEESA 9/3/2024 <3.00 ppt 3.00 ppt Not Detected
PFHpS 9/3/2024 <3.00 ppt 3.00 ppt Not Detected
PFPeS 9/3/2024 <4.00 ppt 4.00 ppt Not Detected
HFPO-DA 9/3/2024 <5.00 ppt 5.00 ppt Not Detected
PFTA 9/3/2024 <8.00 ppt 8.00 ppt Not Detected
NMeFOSAA 9/3/2024 <6.00 ppt 6.00 ppt Not Detected
PFPeS 6/3/2024 <4.00 ppt 4.00 ppt Not Detected
NFDHA 6/3/2024 <20.00 ppt 20.00 ppt Not Detected
PFEESA 6/3/2024 <3.00 ppt 3.00 ppt Not Detected
PFMBA 6/3/2024 <3.00 ppt 3.00 ppt Not Detected
PFPeA 6/3/2024 <3.00 ppt 3.00 ppt Not Detected
PFMPA 6/3/2024 <4.00 ppt 4.00 ppt Not Detected
8:2 FTS 6/3/2024 <5.00 ppt 5.00 ppt Not Detected
4:2 FTS 6/3/2024 <3.00 ppt 3.00 ppt Not Detected
6:2 FTS 6/3/2024 <5.00 ppt 5.00 ppt Not Detected
PFBA 6/3/2024 <5.00 ppt 5.00 ppt Not Detected
PFHpS 6/3/2024 <3.00 ppt 3.00 ppt Not Detected
11Cl-PF3OUdS 6/3/2024 <5.00 ppt 5.00 ppt Not Detected
HFPO-DA 6/3/2024 <5.00 ppt 5.00 ppt Not Detected
PFUnA 6/3/2024 <2.00 ppt 2.00 ppt Not Detected
PFHxA 6/3/2024 <3.00 ppt 3.00 ppt Not Detected
PFDoA 6/3/2024 <3.00 ppt 3.00 ppt Not Detected
PFDA 6/3/2024 <3.00 ppt 3.00 ppt Not Detected
PFOA 6/3/2024 <4.00 ppt 4.00 ppt Not Detected
PFOS 6/3/2024 4.70 ppt 4.00 ppt Detected
PFNA 6/3/2024 <4.00 ppt 4.00 ppt Not Detected
PFHxS 6/3/2024 3.40 ppt 3.00 ppt Detected

Health-based violations on Stillwater Utilities Authority

80 health-based rows in the tables above map to MCL or treatment-technique exceedances, verify each contaminant code on the federal SDWIS report for OK1021220.

Sources: EPA SDWIS

Nationwide peers

160 violations · 53,000 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 Stillwater Utilities Authority

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

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