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Community Water System · PWS OK2002901

Hollis

Operator location Hollis, Oklahoma - 88% of 1,004 violations are health-based (upper-third health share (> 23%)); groundwater source; 2,264 served per SDWIS.

2,264
People served (this PWS)
1,004
EPA violations (this PWS)
886
Health-based (this PWS)
Untested
UCMR5 (this PWS)
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Hollis standing, high SDWIS violation third

88% of 1,004 recorded violations are health-based - upper-third health share (> 23%). Corpus terciles use 29,740 systems serving 500+ (the sitemap cohort). Health-based share 88% is upper-third health share (> 23%). Population rank #12,661 of 29,740 among systems serving 500+.

The verdict

Hollis sits in the upper third of the sitemap cohort by violation count (1,004), so the tables below sample a dense compliance trail rather than a near-clean ledger. Population served is mid-pack at 2,264 (mid served population (≤ 3,309)). Health-based share is 88% - most of this ledger is MCL or treatment-technique exceedance. No UCMR5 PFAS test appears for this system in this extract.

#12,661 of 29,740
Population · /systems
#223 of 558
Population · OK
1,004
Total EPA violations on record
88%
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
957
County
Harmon
School/Daycare
No
MCL Violations
886
Monitoring Violations
44
Treatment Tech Violations
0

Violation History

Contaminant violations recorded by EPA.

Contaminant Category Count Latest
Nitrate-Nitrite MCL 545 2024
Nitrate MCL 323 2003
Nitrate-Nitrite MR 22 2010
Coliform (TCR) MCL 18 2011
Coliform (TCR) MR 8 2004
Total Haloacetic Acids (HAA5) MR 4 2022
TTHM MR 4 2022
Lead and Copper Rule MR 3 2024
Chlorine MR 3 2016

Violation Count vs. the National Corpus

Hollis has 1,004 recorded EPA violations, 99% of the 29,740 public water systems serving 500+ people nationwide carry fewer, and 1% carry more. 88% of this system's own violations are health-based (886 of 1,004), and it ranks #12,661 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)

1,004 Higher than most more violations than 99% 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

Health-based violations on Hollis

886 health-based rows in the tables above map to MCL or treatment-technique exceedances, verify each contaminant code on the federal SDWIS report for OK2002901.

Sources: EPA SDWIS

Nationwide peers

1,004 violations · 2,264 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 near this population served

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

4 peers

What to do with Hollis

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