Seminole County Water Quality: 202 Violations (OK)
16 water systems · 8 ZIP codes · Grade A · Updated 2026-06-04
Data: EPA Safe Drinking Water Information System (SDWIS), EPA ECHO Last verified: 2026-06-04
Violation Trend
EPA violations across water systems in Seminole County.
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Seminole County has 16 community water systems serving approximately 62,442 people across 8 ZIP codes. These systems have accumulated 202 EPA violations, including 119 health-based violations.
Health-based violations account for 59% of all violations in Seminole County. These violations indicate contaminant levels that may pose direct risks to human health.
Violation Breakdown
| Violation Type | Count | Percentage |
|---|---|---|
| Health-based | 119 | 58.9% |
| Monitoring/Reporting | 83 | 41.1% |
| Total | 202 | 100% |
Health-based violations indicate contaminant levels exceeding EPA Maximum Contaminant Levels (MCLs). Monitoring violations indicate failures to test or report.
Cities with Most Violations
| Rank | City | Violations | Health-Based | ZIP Codes | Population |
|---|---|---|---|---|---|
| 1 | Wewoka | 134 | 97 | 1 | 18,103 |
| 2 | Sasakwa | 22 | 2 | 1 | 2,860 |
| 3 | Konawa | 19 | 1 | 1 | 1,479 |
| 4 | Cromwell | 19 | 18 | 1 | 337 |
| 5 | Bowlegs | 5 | 1 | 1 | 2,500 |
| 6 | Maud | 3 | 0 | 1 | 14,906 |
Violation Trend
Year-by-year EPA violations across water systems in Seminole County:
| Year | Total | Health-Based |
|---|---|---|
| 2022 | 10 | 10 |
| 2023 | 7 | 7 |
| 2024 | 20 | 20 |
| 2025 | 28 | 28 |
Most Common Contaminants
| Contaminant | Category | Violations | ZIPs Affected | Health-Based |
|---|---|---|---|---|
| Haloacetic Acids (HAA5) | Disinfection Byproducts | 92 | 2 | Yes |
| Fecal Coliform | Microbiological | 31 | 1 | Yes |
| Stage 2 DBP Rule | Treatment Technique | 14 | 4 | Yes |
| Revised Total Coliform Rule | Microbiological | 12 | 5 | No |
| Surface Water Treatment Rule | Treatment Technique | 9 | 4 | No |
| Chlorite | Disinfection Byproducts | 9 | 1 | Yes |
| Total Organic Carbon | Disinfection Byproducts | 7 | 2 | No |
| Total Coliform | Microbiological | 4 | 1 | No |
| Total Trihalomethanes (TTHM) | Disinfection Byproducts | 3 | 2 | No |
| E. coli | Microbiological | 2 | 1 | Yes |
Understanding Water Quality Scores
Each ZIP code in Seminole County receives a safety score from 0-100 based on EPA compliance data. Scores factor in the number and severity of violations, with health-based violations weighted more heavily than monitoring failures. Resolved violations (where the system returned to compliance) receive reduced weight in the scoring.
The county-level grade (A) represents the average across all 8 ZIP codes. Individual ZIP codes may vary significantly — a county with a B grade may contain both A-rated and D-rated areas.
Water Systems in Seminole County
Seminole County is served by 16 community water systems, averaging 2.0 systems per ZIP code. Each system is independently regulated and tested by the EPA. Larger systems serving more people typically have more extensive monitoring requirements.
Water systems in Seminole County source water from a mix of surface water (rivers, reservoirs) and groundwater (wells, aquifers). Source type affects which contaminants are most likely to be detected.
How to Check Your Water in Seminole County
Enter your ZIP code on ZipCheckup for detailed water system data including contaminant levels, violation history, and safety scores
Request your CCR — every water utility must provide an annual Consumer Confidence Report
Get a home test — certified kits ($20-$50) or professional lab tests ($150-$400) can detect contaminants not covered by routine testing
Consider filtration — NSF-certified filters can address specific contaminants found in your area
Check for lead — homes built before 1986 should test for lead regardless of utility compliance
EPA Enforcement
The EPA and state regulators have taken 71 enforcement actions against water systems in Seminole County. Enforcement actions range from compliance assistance and administrative orders to formal penalties. Systems under enforcement are required to remediate violations and may face ongoing monitoring requirements.
Data Sources
- Water quality: EPA Safe Drinking Water Information System (SDWIS)
- Enforcement: EPA ECHO
Updated daily.
Water Quality Map: Seminole County, OK
Each dot represents a ZIP code. Color indicates water quality grade. Tap a dot for details.
Water Quality by ZIP Code in Seminole County
Water quality varies across Seminole County's 8 ZIP codes. Check your specific ZIP for detailed contaminant data.
What are EPA health violations?
Health-based violations mean a contaminant was detected above the EPA's Maximum Contaminant Level (MCL) — the legal limit designed to protect human health. Seminole County has 119 such violations. Not all violations cause illness, but repeated exceedances increase risk, especially for children and immunocompromised individuals.
What is a water quality grade?
ZipCheckup grades water systems from A to F based on EPA violation history, contaminant levels, and system compliance. Grade A means few or no violations; Grade F indicates persistent or serious issues. Seminole County's overall grade is A.
Not sure if your water needs a filter?
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Find the Right Filter →Frequently Asked Questions
Is the tap water safe in Seminole County, Oklahoma?
Seminole County has 16 community water systems with 202 recorded EPA violations, including 119 health-based. Water quality varies by ZIP code — check your specific location for detailed results.
How many water violations does Seminole County have?
Seminole County has 202 total EPA violations across 8 ZIP codes. 119 are health-based violations indicating contaminant levels potentially harmful to health.
Which city in Seminole County has the most water violations?
Wewoka has the most violations in Seminole County with 134 recorded EPA violations across 1 ZIP codes.
What contaminants are found in Seminole County water?
Seminole County water systems are monitored for over 90 EPA-regulated contaminants including lead, copper, nitrates, disinfection byproducts, and bacteria. Check your ZIP code for contaminant-specific data.
How can I test my water in Seminole County?
Contact your local water utility for free or low-cost testing. You can also use a certified home test kit ($20-$50) or hire a certified lab ($150-$400).