Duncan, OK: 15 Health Violations — 61/100 (2026)
3 ZIP codes · 5 water systems · Updated 2026-06-03
Across water systems in Duncan, safety results are uneven — a portion carry active or recent violations, while others meet federal standards without incident, placing the city in the middle tier for OK.
How Duncan Compares
Data: EPA SDWIS Last verified: 2026-06-03
What You Should Know About Duncan Water
- Your city's water systems recorded 30 violations in the past 5 years.
- Estimated remediation: $1,333 per household.
- CDC health risk index: 15.6 — above typical levels.
Who Supplies Your Water in Duncan
Multiple utilities divide Duncan, OK's water service — 3 leading providers among 5 on the federal register.
Overview
We track water quality and home safety data for 3 ZIP codes in Duncan, Oklahoma, covering 5 community water systems serving approximately 27,935 people.
3 of 3 ZIP codes (100%) have recorded EPA violations. 15 health-based violations documented.
Home Safety Score
Average Home Safety Score for Duncan: C (61/100)
The score combines three factors:
| Factor | What It Measures |
|---|---|
| Water Quality | EPA violations and compliance history |
| Lead Levels | 90th percentile lead concentration vs EPA action level |
| Radon Risk | EPA radon zone classification |
Water Sources
Duncan water systems draw from: Surface water.
Lead & Copper
- Lead data: not yet available for Duncan
- 0 ZIP codes exceed the EPA lead action level
Radon Risk
Dominant radon zone: Zone 3 (Low Risk)
- Zone 1 (High): 0 ZIP codes
- Zone 2 (Moderate): 0 ZIP codes
- Zone 3 (Low): 3 ZIP codes
Top Contaminants
| Contaminant | Category | Violations | ZIPs Affected |
|---|---|---|---|
| Chlorite | Disinfection Byproducts | 20 | 3 |
| Consumer Confidence Report Rule | Reporting | 12 | 3 |
| Contaminant 1006 | Other | 4 | 3 |
| Haloacetic Acids (HAA5) | Disinfection Byproducts | 4 | 3 |
Areas with Most Violations
| ZIP Code | Safety Score | Violations | Health-Based | System |
|---|---|---|---|---|
| 73533 | C | 10 | 5 | Duncan Public Utilities Authority |
| 73534 | C | 10 | 5 | Duncan Public Utilities Authority |
| 73536 | C | 10 | 5 | Duncan Public Utilities Authority |
All ZIP Codes in Duncan
Data Sources
- Water quality: EPA Safe Drinking Water Information System (SDWIS)
- Lead/copper: EPA Lead and Copper Rule sampling data
- Radon: EPA Map of Radon Zones
Updated daily.
Health Outcomes in Duncan
Source: CDC PLACES (County-level estimates). Water contamination can correlate with respiratory and chronic health conditions.
Compared to National Average
Vertical line = national average. ■ Above national · ■ Below national
Top Contaminants in Duncan Water
Based on EPA violation records. Check your ZIP code report for system-specific contaminant data.
Cost Context: What Remediation Means for Duncan Homeowners
Because property values in Duncan comfortably exceed estimated remediation costs, the equity impact here is proportionally small.
Remediation costs in Duncan are relatively low compared to home values. The $767–$2,633 estimated range is a small fraction of median property value. Home values are 5% below the Oklahoma average.
Flood & Climate Risk in Duncan
67 FEMA flood insurance claims are on file for Duncan, and 33% of local ZIP codes fall within federally designated flood zones — enough to put flood exposure on the planning radar, though short of the concentrated-risk threshold where treatment-system vulnerability becomes a primary consideration.
Duncan has a moderate flood history with 67 FEMA claims averaging $8,191 per payout. 33% of ZIP codes fall within FEMA flood zones. Flood events can contaminate drinking water and overwhelm treatment systems.
How flooding affects water quality: Flood events can introduce sewage, agricultural runoff, and industrial chemicals into water supplies. Even after floodwaters recede, contamination can persist in wells and aging infrastructure. Flood damage can add significantly to the estimated <strong>$1,333</strong> remediation cost per household.
Residents in flood-prone areas should consider flood insurance even outside FEMA zones — over 25% of flood claims come from low-to-moderate risk areas. After any flood event, test your water before drinking.
Source: FEMA National Flood Insurance Program (NFIP) claims data, FEMA flood zone designations.
What You Can Do in Duncan
- Test your water at home. City-level data shows averages — your tap may differ. NSF-certified test kits cost $20-40 and give results in days.
- Install a certified water filter. Filters rated for Chlorite can reduce the most common contaminant found in Duncan's water.
- Check your home's plumbing. Homes built before 1986 may have lead solder in pipes. A licensed plumber can assess your risk.
Deep Dive Reports
Detailed analysis for Duncan, OK