Yankton, SD 57078
3 water systems • 15,686 residents
Poor water quality - filtration recommended
Score: 38/100
Graded on EPA violations, contaminants, severity, compliance, and enforcement history. See methodology.
Data updated June 2026 • Sources: EPA ECHO and EPA Envirofacts
20
Contaminants Detected
297
Violations on Record
83
Health-Based Violations
0
Recent Violations
Grade Breakdown
38 / 100 points
Recommended Water Filters
- ✓Point-of-Use Carbon Filter (NSF-certified for lead)
- ✓Reverse Osmosis or Ion Exchange Filter
- ✓Ultraviolet (UV) Purification
- ✓Activated Carbon Filter (disinfection byproducts)
- ✓Whole Home Carbon Filter System
Consult a water quality specialist for personalized recommendations.
Yankton vs SD & National Average
Detected Contaminants
20 contaminants detected across water systems serving this ZIP code
| Contaminant | Category |
|---|---|
| Atrazine | Agricultural |
| Nitrate | Agricultural |
| TTHM | Disinfection Byproduct |
| Lead and Copper Rule | Heavy Metal |
| Coliform (TCR) | Microorganism |
| Revised Total Coliform Rule | Microorganism |
| 2,4-D | Other |
| 2,4,5-TP | Other |
| Chlorine | Other |
| Consumer Confidence Rule | Other |
| Dalapon | Other |
| Dinoseb | Other |
| Pentachlorophenol | Other |
| Picloram | Other |
| Public Notice | Other |
| Stage 1 Disinfectants and Disinfection Byproducts Rule | Other |
| Stage 2 Disinfectants and Disinfection Byproducts Rule | Other |
| Surface Water Treatment Rule | Other |
| Combined Radium (-226 and -228) | Radiological |
| Gross Alpha, Excl. Radon and U | Radiological |
Water System Information
- Systems Serving This ZIP:
- TIMBERLAND PARK, EAST WINDS COURT, INC., YANKTON
- Population Served:
- 15,686
- Systems With Violations:
- 3 of 3
- Major Violations:
- 113
- Enforcement Actions:
- 279
Frequently Asked Questions
What does the grade mean?
Our A–F grade ranks this ZIP code's water quality against every other analyzed ZIP in the country, based on EPA data. A = among the best, F = among the most troubled.
Is my tap water safe to drink?
Water systems regulated by the EPA must comply with Safe Drinking Water Act standards. However, if you're concerned about water quality, consider a water filter appropriate for your contaminants.
How often is the data updated?
We update our data quarterly with the latest EPA ECHO and Envirofacts data. Historical violations are tracked to identify patterns.
What filters do you recommend?
Filter recommendations are based on detected contaminants in your area. See our Filter Guide for detailed information about different filter types.