Big Horn County, Wyoming
12 ZIP codes · Avg score 60/100 · Grade C · Updated 2026-06-04
Based on current EPA data, Big Horn County's 12 ZIP codes reflect fair but mixed water safety.
How Big Horn County Compares
How Big Horn County Compares
Big Horn County scores 5 points above the Wyoming state average (55/100) and 8 points below the national average (68/100).
Data: EPA SDWIS Last verified: 2026-06-04
ZIP Code Risk Map
Water Quality Map: Big Horn County, Wyoming
Each dot represents a ZIP code. Color indicates water quality grade. Tap a dot for details.
Key Risk Factors
Health risk index: 13.8 (asthma 10.3%, diabetes 12.6%)
Estimated additional annual cost per homeowner: $648, driven primarily by water_lead
Infrastructure: 0.385% avg pipe failure probability, 36% of ZIPs at high risk
69.7% of homes built before 1978 (lead paint era)
Violation History (2022–2024)
→ Stable trendEPA violation counts by year across Big Horn County water systems. Health-based shown in red, total in blue.
Peak year: 2022 with 3 violations. Past 5 years: 5 total (5 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: $648
Bar widths proportional to share of total annual risk cost. Source: compound risk model (FEMA, EPA, USGS).
Housing Age Distribution
5,189 housing units in Big Horn 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 Big Horn County
Remediation costs are relatively manageable for most homeowners in Big Horn 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 Big Horn 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 Big Horn County ranked by EPA violation count.
| # | Water System | Population | Violations |
|---|---|---|---|
| 1 | Manderson, Town of | 110 | 8 |
| 2 | Basin, Town of | 1,250 | 6 |
| 3 | South Big Horn County Jpb | 900 | 6 |
| 4 | Lovell, Town of | 2,360 | 6 |
| 5 | South End Water Users S&i District | 150 | 6 |
15 total water systems serve Big Horn County.
All ZIP Codes in Big Horn County
12 ZIP codes tracked in Big Horn County.
| # | ZIP Code | City | Safety Score | Grade | Violations | Home Value |
|---|---|---|---|---|---|---|
| 1 | 82441 | Shell | 70 | B | 0 | $381K |
| 2 | 82410 | Basin | 69 | C | 6 (1 health) | $185K |
| 3 | 82412 | Byron | 66 | C | 0 | $164K |
| 4 | 82421 | Deaver | 66 | C | 0 | $156K |
| 5 | 82426 | Greybull | 66 | C | 2 | $190K |
| 6 | 82428 | Hyattville | 66 | C | 1 | $93K |
| 7 | 82411 | Burlington | 64 | C | 4 (2 health) | $173K |
| 8 | 82420 | Cowley | 63 | C | 3 | $229K |
| 9 | 82431 | Lovell | 57 | C | 6 | $217K |
| 10 | 82432 | Manderson | 49 | D | 2 (1 health) | — |
| 11 | 82422 | Emblem | 40 | D | 0 | — |
| 12 | 82434 | Otto | 40 | D | 0 | — |
Recommended Buyer Guides for Big Horn County
Editorial methodology pairs each documented risk in this county with the buyer category that addresses it, drawing on water-quality detections, housing-stock lead exposure, EPA Radon Zone designation, and FEMA flood and wildfire ratings. NSF-certified options surface where applicable, and products that match the specific contaminant take priority.
- Best Lead Paint Test Kits — 69.7% 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
Deep Dive Reports
Detailed analysis for Big Horn County, Wyoming
Overview
Big Horn County in Wyoming covers 12 ZIP codes with an average Home Safety Score of C (60/100).
7 of 12 ZIP codes have recorded EPA violations. 4 health-based violations have been documented.
← Back to Wyoming 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.