Otoe-Missouria Tribe

PWSID: OK1021222

No active violations
This system has no unresolved violations. The most recent violation on record was 2023-01-01.

This system has more violations on record than 86% of water systems in Oklahoma.

Violation trend: 2.2 per year over the last 5 years, down from 14.0 per year in the previous 5.

System Details

Population Served250
Service Connections92
Water SourceSurface Water
System TypeCommunity Water System
OwnerNative American
StatusActive
CityRed Rock
EPA ZIP on File74651

Lead & Copper Testing

ContaminantLevelEPA Action LevelStatus
Lead (90th percentile)0.0125 mg/L0.015 mg/LBelow Action Level
Lead (90th percentile)0.0033 mg/L0.015 mg/LBelow Action Level
Lead (90th percentile)0.0013 mg/L0.015 mg/LBelow Action Level
Lead (90th percentile)0.0000 mg/L0.015 mg/LBelow Action Level
Lead (90th percentile)0.0000 mg/L0.015 mg/LBelow Action Level

Violation History (173 total)

ContaminantViolationDateHealth-BasedStatus
2950MCL
Measured: 0.0820 MG/L (limit: 0.0800 MG/L)
2023-01-01YesReturned to Compliance
2950MCL
Measured: 0.0820 MG/L (limit: 0.0800 MG/L)
2023-01-01YesReturned to Compliance
2950MCL
Measured: 0.0820 MG/L (limit: 0.0800 MG/L)
2023-01-01YesAcknowledged
2950MCL
Measured: 0.0830 MG/L (limit: 0.0800 MG/L)
2022-07-01YesAcknowledged
2950MCL
Measured: 0.0830 MG/L (limit: 0.0800 MG/L)
2022-07-01YesReturned to Compliance
2950MCL
Measured: 0.0830 MG/L (limit: 0.0800 MG/L)
2022-07-01YesReturned to Compliance
2950MCL
Measured: 0.0830 MG/L (limit: 0.0800 MG/L)
2022-07-01YesAcknowledged
2950MCL
Measured: 0.0850 MG/L (limit: 0.0800 MG/L)
2022-01-01YesReturned to Compliance
2950MCL
Measured: 0.0850 MG/L (limit: 0.0800 MG/L)
2022-01-01YesReturned to Compliance
2950MCL
Measured: 0.0900 MG/L (limit: 0.0800 MG/L)
2021-10-01YesReturned to Compliance
2950MCL
Measured: 0.0860 MG/L (limit: 0.0800 MG/L)
2021-07-01YesReturned to Compliance
2950MCL
Measured: 0.0900 MG/L (limit: 0.0800 MG/L)
2021-04-01YesReturned to Compliance
2950MCL
Measured: 0.0910 MG/L (limit: 0.0800 MG/L)
2021-01-01YesReturned to Compliance
2950MCL
Measured: 0.0830 MG/L (limit: 0.0800 MG/L)
2020-10-01YesReturned to Compliance
2950MCL
Measured: 0.0810 MG/L (limit: 0.0800 MG/L)
2019-10-01YesReturned to Compliance
2456MCL
Measured: 0.1300 MG/L (limit: 0.0600 MG/L)
2019-07-01YesReturned to Compliance
2950MCL
Measured: 0.1420 MG/L (limit: 0.0800 MG/L)
2019-07-01YesReturned to Compliance
2456MCL
Measured: 0.1370 MG/L (limit: 0.0600 MG/L)
2019-04-01YesReturned to Compliance
2950MCL
Measured: 0.1820 MG/L (limit: 0.0800 MG/L)
2019-04-01YesReturned to Compliance
2456MCL
Measured: 0.1470 MG/L (limit: 0.0600 MG/L)
2019-01-01YesReturned to Compliance
2950MCL
Measured: 0.2110 MG/L (limit: 0.0800 MG/L)
2019-01-01YesReturned to Compliance
2920TT2019-01-01YesReturned to Compliance
2456MCL
Measured: 0.1600 MG/L (limit: 0.0600 MG/L)
2018-10-01YesReturned to Compliance
2950MCL
Measured: 0.2430 MG/L (limit: 0.0800 MG/L)
2018-10-01YesReturned to Compliance
2920TT2018-10-01YesReturned to Compliance
0300TT2018-08-01YesReturned to Compliance
0200TT2018-08-01YesReturned to Compliance
2456MCL
Measured: 0.0840 MG/L (limit: 0.0600 MG/L)
2018-07-01YesReturned to Compliance
2950MCL
Measured: 0.2170 MG/L (limit: 0.0800 MG/L)
2018-07-01YesReturned to Compliance
2920TT2018-07-01YesReturned to Compliance
2950MCL
Measured: 0.2070 MG/L (limit: 0.0800 MG/L)
2018-04-01YesReturned to Compliance
2456MCL
Measured: 0.0710 MG/L (limit: 0.0600 MG/L)
2018-04-01YesReturned to Compliance
2950MR2018-04-01Returned to Compliance
2456MR2018-04-01Returned to Compliance
2920TT2018-04-01YesReturned to Compliance
0300TT2018-02-01YesReturned to Compliance
2950MCL
Measured: 0.2300 MG/L (limit: 0.0800 MG/L)
2018-01-01YesReturned to Compliance
2456MCL
Measured: 0.0890 MG/L (limit: 0.0600 MG/L)
2018-01-01YesReturned to Compliance
2920TT2018-01-01YesReturned to Compliance
2950MCL
Measured: 0.2110 MG/L (limit: 0.0800 MG/L)
2017-10-01YesAcknowledged
2950MCL
Measured: 0.2110 MG/L (limit: 0.0800 MG/L)
2017-10-01YesReturned to Compliance
2456MCL
Measured: 0.0860 MG/L (limit: 0.0600 MG/L)
2017-10-01YesAcknowledged
2456MCL
Measured: 0.0860 MG/L (limit: 0.0600 MG/L)
2017-10-01YesReturned to Compliance
2920TT2017-10-01YesAcknowledged
2920TT2017-10-01YesReturned to Compliance
2950MCL
Measured: 0.2260 MG/L (limit: 0.0800 MG/L)
2017-07-01YesAcknowledged
2950MCL
Measured: 0.2260 MG/L (limit: 0.0800 MG/L)
2017-07-01YesReturned to Compliance
2456MCL
Measured: 0.0650 MG/L (limit: 0.0600 MG/L)
2017-07-01YesAcknowledged
2456MCL
Measured: 0.0650 MG/L (limit: 0.0600 MG/L)
2017-07-01YesReturned to Compliance
2920TT2017-07-01YesAcknowledged

Showing 50 of 173 historical violations.

Understanding This Water System's Record

Otoe-Missouria Tribe is a community water system water system that draws from surface water sources and serves a population of 250 in Red Rock, Oklahoma. This page shows its complete compliance history as reported to the EPA's Safe Drinking Water Information System (SDWIS), the federal database that tracks every public water system in the United States.

What Do These Violations Mean?

Health-based violations mean the system exceeded an EPA maximum contaminant level (MCL) or failed to provide required treatment. These indicate potential health risks from contaminants like lead, arsenic, bacteria, nitrates, or disinfection byproducts. Non-health-based violations involve monitoring, reporting, or procedural requirements — the system missed a testing deadline or failed to notify customers, but contaminant levels were not necessarily unsafe.

What Should You Do?

Your water utility is required to publish an annual Consumer Confidence Report (CCR) that details test results and any violations. If your system has active health-based violations, consider a certified water filter rated for the specific contaminants involved. The contaminant guides on this site explain health risks and filter options for common pollutants. For the most current results, contact your water utility directly — EPA data can lag weeks or months behind real-time testing.