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Community Water System · PWS OK1021222

Otoe-Missouria Tribe

Red Rock, Oklahoma 74651 - drinking water served from surface water sources to 250 people, tracked in EPA SDWIS and UCMR5.

250
People served
1,707
EPA violations
1,001
Health-based
Untested
UCMR5 result

The verdict

EPA records 1,707 drinking-water violations at Otoe-Missouria Tribe, 59% of them health-based - above the Oklahoma per-system average.

1,707
Total EPA violations on record
59%
Health-based (MCL / treatment failure)
250
People served by this system
N/A
PFAS compounds detected (UCMR5)

Water Quality Snapshot: Otoe-Missouria Tribe

Otoe-Missouria Tribe is a native american-owned community water system that delivers drinking water to 250 residents in Red Rock, Oklahoma (Noble County) through 92 service connections. Its water is drawn from surface water sources. EPA's Safe Drinking Water Information System records 1,707 total violations for this system , of which 1,001 (59%) are health-based, meaning a contaminant exceeded an EPA Maximum Contaminant Level or a required treatment technique failed. A further 696 monitoring and reporting violations are on file. The most recent violation on record dates to 2023.

The most frequently cited contaminant at this system is TTHM, recorded in 473 violations (MCL, health-based). This system has not yet been sampled under EPA's UCMR5 PFAS monitoring program, so no PFAS detection data is available here.

Across Oklahoma, EPA tracks 1,262 public water systems serving 3,699,452 people, with 336,706 cumulative violations and 113,804 health-based violations on record. About 98% of systems in the state carry at least one violation, and state-wide the average per system is 266.8 violations. Statewide, 101 of 166 UCMR5-tested systems have reported PFAS detections (60.8%).

Otoe-Missouria Tribe's 1,707 violations sit above the Oklahoma average.

All figures above are sourced directly from EPA SDWIS and UCMR5 public data releases and are updated as EPA publishes new reporting cycles.

Population Served
250
Total Violations
1,707
Health-Based Violations
1,001
Water Source
Surface Water

System Details

System Type
Community
Owner Type
Native American
Connections
92
County
Noble
School/Daycare
No
MCL Violations
574
Monitoring Violations
696
Treatment Tech Violations
427

Violation History

Contaminant violations recorded by EPA.

Contaminant Category Count Latest
TTHM MCL 473 2023
CARBON, TOTAL TT 388 2019
Interim Enhanced Surface Water Treatment Rule MR 297 2016
CARBON, TOTAL MR 191 2011
Total Haloacetic Acids (HAA5) MCL 101 2019
Coliform (TCR) MR 64 2011
TTHM MR 56 2018
Total Haloacetic Acids (HAA5) MR 50 2018
Interim Enhanced Surface Water Treatment Rule TT 33 2018
Lead and Copper Rule MR 13 2011
Nitrate-Nitrite MR 10 2016
Consumer Confidence Rule Other 7 2016
Chlorine MR 5 2004
Surface Water Treatment Rule TT 4 2018
Stage 2 Disinfectants and Disinfection Byproducts Rule MR 3 2010
E. COLI MR 2 2008
Long Term 2 Enhanced Surface Water Treatment Rule TT 2 2010
Nitrate MR 2 2002
Long Term 2 Enhanced Surface Water Treatment Rule MR 2 2008
Surface Water Treatment Rule MR 1 2004

Verify This Water System

The figures above are aggregated from EPA's public databases. To verify the underlying records, or to file a complaint, request a Consumer Confidence Report, or check current monitoring status, go directly to the federal and state regulators that enforce the Safe Drinking Water Act for Otoe-Missouria Tribe.

Federal Source of Truth

EPA SDWIS, Federal Reports

EPA's Safe Drinking Water Information System (SDWIS) holds the federal compliance record for every regulated public water system. Open the system-level report by PWS ID:

View PWS ID OK1021222 on SDWIS

Source: EPA SDWIS Federal Reports Search

State Regulator

Oklahoma Drinking Water Authority

Oklahoma's primacy agency administers the Safe Drinking Water Act locally. Search EPA SDWIS for the current state contact, or use the state's public health or environment department portal.

Find OK regulator via EPA SDWIS

Violation Timeline

Each row links to the EPA SDWIS public record for verification. Cross-reference the contaminant code on EPA's federal report to see violation dates, return-to-compliance status, and enforcement actions.

Year (latest) Contaminant Category Count EPA Record
2023 TTHM MCL 473 SDWIS / OK1021222 / 2950
2019 CARBON, TOTAL TT 388 SDWIS / OK1021222 / 2920
2019 Total Haloacetic Acids (HAA5) MCL 101 SDWIS / OK1021222 / 2456
2018 TTHM MR 56 SDWIS / OK1021222 / 2950
2018 Total Haloacetic Acids (HAA5) MR 50 SDWIS / OK1021222 / 2456
2018 Interim Enhanced Surface Water Treatment Rule TT 33 SDWIS / OK1021222 / 0300
2018 Surface Water Treatment Rule TT 4 SDWIS / OK1021222 / 0200
2016 Interim Enhanced Surface Water Treatment Rule MR 297 SDWIS / OK1021222 / 0300
2016 Nitrate-Nitrite MR 10 SDWIS / OK1021222 / 1038
2016 Consumer Confidence Rule Other 7 SDWIS / OK1021222 / 7000
2011 CARBON, TOTAL MR 191 SDWIS / OK1021222 / 2920
2011 Coliform (TCR) MR 64 SDWIS / OK1021222 / 3100
2011 Lead and Copper Rule MR 13 SDWIS / OK1021222 / 5000
2010 Stage 2 Disinfectants and Disinfection Byproducts Rule MR 3 SDWIS / OK1021222 / 0600
2010 Long Term 2 Enhanced Surface Water Treatment Rule TT 2 SDWIS / OK1021222 / 0800

How Otoe-Missouria Tribe Compares

Cross-reference this system's record against state averages and the federal MCL framework for context.

Metric Otoe-Missouria Tribe Oklahoma avg Federal benchmark
Total violations 1,707 266.8 SDWA compliance, any non-zero count is a recorded breach
Health-based violations 1,001 90.2 Indicates a contaminant exceeded a federal MCL
PFAS detection None 60.8% EPA final rule (2024): PFOA/PFOS MCL = 4.0 ppt
Population served 250 2,931 Sizing context for compliance burden

Sources: EPA SDWIS and EPA National Primary Drinking Water Regulations (40 CFR Part 141). State averages computed across 1,262 regulated public water systems in Oklahoma.

Federal MCL reference, Safe Drinking Water Act thresholds ▼
Contaminant Federal MCL / Action Level Note
Lead 0 mg/L (Action Level: 0.015 mg/L) Lead and Copper Rule treatment technique
Arsenic 0.010 mg/L (10 ppb) Health-based MCL since 2006
Total Coliform Treatment technique (RTCR) Indicator organism, monitoring trigger
PFOA / PFOS (PFAS) 4.0 ppt each (final 2024 rule) Compliance deadline 2029 (EPA proposed extending to 2031, not yet final as of May 2026)
Nitrate (as N) 10 mg/L Acute health risk for infants

Frequently Asked Questions

Is Otoe-Missouria Tribe water safe to drink? ▼
Otoe-Missouria Tribe (PWS ID: OK1021222) has 1707 recorded violations in the EPA SDWIS database. No PFAS contamination was detected in UCMR5 testing. This system serves 250 people using Surface Water sources.
How many people does Otoe-Missouria Tribe serve? ▼
Otoe-Missouria Tribe serves 250 people in Red Rock, Oklahoma. It is a Native American-owned system using Surface Water water sources with 92 service connections.
What type of violations does Otoe-Missouria Tribe have? ▼
Otoe-Missouria Tribe has 1,707 total violations: 1,001 health-based violations (MCL exceedances or treatment failures), 696 monitoring/reporting violations, and 427 treatment technique violations. Health-based violations indicate contaminant levels exceeded EPA safe limits.
Has PFAS been detected in Otoe-Missouria Tribe water? ▼
No PFAS testing data is available for Otoe-Missouria Tribe under the EPA's UCMR5 monitoring program.
What water source does Otoe-Missouria Tribe use? ▼
Otoe-Missouria Tribe uses Surface Water as its primary water source. It is classified as a Community Water System (CWS), serving residential populations year-round.
Where does this data come from? ▼
All data comes from the EPA Safe Drinking Water Information System (SDWIS) and the UCMR5 PFAS monitoring program. SDWIS tracks compliance for all public water systems regulated under the Safe Drinking Water Act.
Data Sources: EPA Safe Drinking Water Information System (SDWIS), Q4 2025. This data is provided for informational purposes only.

Read our methodology - how this data is sourced, computed, and verified.

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

Every figure on PlainWater is rendered directly from EPA SDWIS drinking-water data, no number is typed in by an editor. This system's figures are rendered directly from EPA SDWIS data, no figure is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error.