Yankton County, South Dakota
8 ZIP codes · Avg score 61/100 · Grade C · Updated 2026-06-04
Yankton County's water quality grade reflects a middle-ground assessment — its 8 ZIP codes range from fully compliant to violation-flagged.
How Yankton County Compares
How Yankton County Compares
Yankton County scores 1 points above the South Dakota state average (60/100) and 7 points below the national average (68/100).
Data: EPA SDWIS Last verified: 2026-06-04
ZIP Code Risk Map
Water Quality Map: Yankton County, South Dakota
Each dot represents a ZIP code. Color indicates water quality grade. Tap a dot for details.
Key Risk Factors
Health risk index: 13.3 (asthma 9.8%, diabetes 11.8%)
Estimated additional annual cost per homeowner: $771, driven primarily by flood
Infrastructure: 0.416% avg pipe failure probability, 50% of ZIPs at high risk
74.4% of homes built before 1978 (lead paint era)
Violation History (2021–2025)
→ Stable trendEPA violation counts by year across Yankton County water systems. Health-based shown in red, total in blue.
Peak year: 2025 with 2 violations. Past 5 years: 3 total (3 health-based).
Source: EPA SDWIS historical violations. Data may lag 6–12 months for the most recent year.
County Health Indicators vs National Average
Black markers indicate national averages. Source: CDC PLACES, Census ACS.
Infrastructure Overview
Sources: Census ACS (housing age), EPA SDWIS (infrastructure risk model), state bridge inspection data.
Compound Risk Breakdown
Estimated additional annual cost per homeowner: $771
Bar widths proportional to share of total annual risk cost. Source: compound risk model (FEMA, EPA, USGS).
Housing Age Distribution
11,182 housing units in Yankton County
Source: U.S. Census Bureau ACS B25034 (Year Structure Built).
Water Safety Affordability
How much it costs to fix water issues relative to home values in Yankton County
Remediation costs are relatively manageable for most homeowners in Yankton County, representing a small fraction of property value.
Remediation includes water filtration, lead abatement, radon mitigation, and flood protection where applicable. Source: Census ACS, EPA SDWIS.
Health Outcomes vs National Average
CDC PLACES data for Yankton County residents
Black markers = national averages. Red = above national avg. Green = below. Source: CDC PLACES, Census ACS.
Water Systems with Most Violations
Top 5 systems in Yankton County ranked by EPA violation count.
| # | Water System | Population | Violations |
|---|---|---|---|
| 1 | By Water District | 13,320 | 15 |
| 2 | Lesterville | 115 | 9 |
| 3 | Yankton | 15,411 | 4 |
| 4 | East Winds Court, Inc. | 180 | 4 |
| 5 | Timberland Park | 95 | 4 |
13 total water systems serve Yankton County.
All ZIP Codes in Yankton County
8 ZIP codes tracked in Yankton County.
| # | ZIP Code | City | Safety Score | Grade | Violations | Home Value |
|---|---|---|---|---|---|---|
| 1 | 57045 | Menno | 68 | C | 0 | $114K |
| 2 | 57031 | Gayville | 66 | C | 0 | $138K |
| 3 | 57037 | Irene | 66 | C | 0 | $143K |
| 4 | 57078 | Yankton | 64 | C | 4 (1 health) | $213K |
| 5 | 57046 | Mission Hill | 63 | C | 2 (2 health) | $260K |
| 6 | 57072 | Volin | 63 | C | 0 | $182K |
| 7 | 57040 | Lesterville | 56 | C | 9 | $117K |
| 8 | 57067 | Utica | 40 | D | 0 | $216K |
Recommended Buyer Guides for Yankton County
Filtered against EPA monitoring data and CDC lead-exposure guidance, the guides below skip the generic catalog and connect directly to the contaminants and hazards on file here.
- Best Lead Paint Test Kits — 74.4% of homes built before 1978
- Best Under-Sink Reverse Osmosis Systems — Multi-contaminant removal at the kitchen tap
- Best Radon Test Kits — EPA Radon Zone 1 (highest risk) dominant in county
- Best Sump Pumps — Flood is the top compound risk factor
- Best Mold Test Kits — Flood-driven moisture and mold risk
Deep Dive Reports
Detailed analysis for Yankton County, South Dakota
Overview
Yankton County in South Dakota covers 8 ZIP codes with an average Home Safety Score of C (61/100).
3 of 8 ZIP codes have recorded EPA violations. 3 health-based violations have been documented.
← Back to South Dakota water quality report
Data Sources
- Water quality: EPA Safe Drinking Water Information System (SDWIS)
- Home values: U.S. Census Bureau ACS (median estimates by ZCTA)
Updated daily.