Lyman County, South Dakota
7 ZIP codes · Avg score 50/100 · Grade D · Updated 2026-06-04
Across Lyman County, EPA compliance records for 7 ZIP codes fall well below average — documented health-based violations affect multiple areas, and the county's sustained low grade points to structural rather than temporary shortfalls in the underlying water systems.
How Lyman County Compares
How Lyman County Compares
Lyman County scores 10 points below the South Dakota state average (60/100) and 18 points below the national average (68/100).
Data: EPA SDWIS Last verified: 2026-06-04
ZIP Code Risk Map
Water Quality Map: Lyman 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: 15.7 (asthma 11.2%, diabetes 15.7%)
Estimated additional annual cost per homeowner: $811, driven primarily by water_lead
Infrastructure: 0.404% avg pipe failure probability, 71% of ZIPs at high risk
76.1% of homes built before 1978 (lead paint era)
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: $811
Bar widths proportional to share of total annual risk cost. Source: compound risk model (FEMA, EPA, USGS).
Housing Age Distribution
1,599 housing units in Lyman 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 Lyman County
Remediation costs are relatively manageable for most homeowners in Lyman 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 Lyman County residents
Black markers = national averages. Red = above national avg. Green = below. Source: CDC PLACES, Census ACS.
Water Systems with Most Violations
Top 4 systems in Lyman County ranked by EPA violation count.
| # | Water System | Population | Violations |
|---|---|---|---|
| 1 | Presho | 472 | 1 |
| 2 | Oacoma | 386 | 0 |
| 3 | TRIPP COUNTY WATER USER DISTRICT | 4,860 | 0 |
| 4 | Kennebec | 265 | 0 |
All ZIP Codes in Lyman County
7 ZIP codes tracked in Lyman County.
| # | ZIP Code | City | Safety Score | Grade | Violations | Home Value |
|---|---|---|---|---|---|---|
| 1 | 57568 | Presho | 68 | C | 1 | $163K |
| 2 | 57365 | Oacoma | 66 | C | 0 | $259K |
| 3 | 57544 | Kennebec | 53 | D | 0 | $144K |
| 4 | 57534 | Hamill | 40 | D | 0 | $116K |
| 5 | 57548 | Lower Brule | 40 | D | 0 | $48K |
| 6 | 57569 | Reliance | 40 | D | 0 | $114K |
| 7 | 57576 | Vivian | 40 | D | 0 | $168K |
Recommended Buyer Guides for Lyman County
Editorial-only picks, screened against the EPA detections on file.
- Best Lead Paint Test Kits — 76.1% of homes built before 1978
- Best Radon Test Kits — EPA Radon Zone 1 (highest risk) dominant in county
Deep Dive Reports
Detailed analysis for Lyman County, South Dakota
Overview
Lyman County in South Dakota covers 7 ZIP codes with an average Home Safety Score of D (50/100).
1 of 7 ZIP codes have recorded EPA violations. All violations are monitoring/reporting type.
← 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.
What You Can Do
Lyman County has a grade of D. Here are steps to protect your household.
Test your tap water
Order a certified lab test kit ($20-$50) to check for lead, bacteria, and other contaminants specific to your ZIP code.
Consider a certified water filter
NSF-certified filters can remove most common contaminants. Match the filter to your test results for best protection. Try our filter matcher
Contact your water utility
Request the latest Consumer Confidence Report (CCR) from your water provider. It details exactly what was found in your water supply.
Check for lead in your home
76.1% of homes in this county were built before 1978. Older plumbing and solder can leach lead into drinking water, especially in the morning.