Slope County, North Dakota
1 ZIP code · Avg score 66/100 · Grade C · Updated 2026-06-03
Slope County's water quality grade reflects a middle-ground assessment — its 1 ZIP code range from fully compliant to violation-flagged.
How Slope County Compares
How Slope County Compares
Slope County scores 10 points above the North Dakota state average (56/100) and 2 points below the national average (68/100).
Data: EPA SDWIS Last verified: 2026-06-03
Key Risk Factors
Health risk index: 15.7 (asthma 9.8%, diabetes 14.6%)
Estimated additional annual cost per homeowner: $970, driven primarily by water_lead
Infrastructure: 0.47% avg pipe failure probability, 100% of ZIPs at high risk
83% 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: $970
Bar widths proportional to share of total annual risk cost. Source: compound risk model (FEMA, EPA, USGS).
Housing Age Distribution
109 housing units in Slope 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 Slope County
Water safety remediation is a moderate expense relative to home values. Most homeowners can address issues through staged improvements over time.
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 Slope County residents
Black markers = national averages. Red = above national avg. Green = below. Source: CDC PLACES, Census ACS.
All ZIP Codes in Slope County
1 ZIP code tracked in Slope County.
| # | ZIP Code | City | Safety Score | Grade | Violations | Home Value |
|---|---|---|---|---|---|---|
| 1 | 58643 | Marmarth | 66 | C | 0 | $53K |
Recommended Buyer Guides for Slope County
Methodologically, the recommendation order reflects severity in the federal record: contaminants flagged in EPA detection records for this county outrank generic water concerns, FEMA-confirmed hazard ratings shift emergency-related categories upward, and CDC lead-exposure markers govern when lead-test kits and certified filters appear at the top of the list.
- Best Lead Paint Test Kits — 83% of homes built before 1978
- Best Radon Test Kits — EPA Radon Zone 1 (highest risk) dominant in county
Overview
Slope County in North Dakota covers 1 ZIP code with an average Home Safety Score of C (66/100).
No EPA violations recorded across any tracked ZIP codes in Slope County.
← Back to North 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.