Sheridan County, Montana
9 ZIP codes · Avg score 52/100 · Grade D · Updated 2026-06-04
State safety rankings put Sheridan County near the bottom — 9 ZIP codes, below-average compliance.
How Sheridan County Compares
How Sheridan County Compares
Sheridan County scores 3 points below the Montana state average (55/100) and 16 points below the national average (68/100).
Data: EPA SDWIS Last verified: 2026-06-04
ZIP Code Risk Map
Water Quality Map: Sheridan County, Montana
Each dot represents a ZIP code. Color indicates water quality grade. Tap a dot for details.
Key Risk Factors
Health risk index: 13.9 (asthma 11.1%, diabetes 11.5%)
Estimated additional annual cost per homeowner: $941, driven primarily by energy_code_gap
Infrastructure: 0.416% avg pipe failure probability, 78% of ZIPs at high risk
74.1% 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: $941
Bar widths proportional to share of total annual risk cost. Source: compound risk model (FEMA, EPA, USGS).
Housing Age Distribution
2,042 housing units in Sheridan 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 Sheridan County
Remediation costs are relatively manageable for most homeowners in Sheridan 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 Sheridan 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 Sheridan County ranked by EPA violation count.
| # | Water System | Population | Violations |
|---|---|---|---|
| 1 | Antelope County Water and Sewer | 59 | 6 |
| 2 | Outlook County Sewer and Water | 96 | 4 |
| 3 | Westby Town of | 172 | 1 |
| 4 | MEDICINE LAKE TOWN OF | 600 | 0 |
| 5 | Plentywood Water Department | 1,700 | 0 |
All ZIP Codes in Sheridan County
9 ZIP codes tracked in Sheridan County.
| # | ZIP Code | City | Safety Score | Grade | Violations | Home Value |
|---|---|---|---|---|---|---|
| 1 | 59254 | Plentywood | 70 | B | 0 | $147K |
| 2 | 59275 | Westby | 66 | C | 1 | $80K |
| 3 | 59252 | Outlook | 64 | C | 4 | $103K |
| 4 | 59211 | Antelope | 60 | C | 6 | — |
| 5 | 59247 | Medicine Lake | 50 | D | 0 | $90K |
| 6 | 59219 | Dagmar | 40 | D | 0 | $115K |
| 7 | 59242 | Homestead | 40 | D | 0 | $123K |
| 8 | 59256 | Raymond | 40 | D | 0 | — |
| 9 | 59258 | Reserve | 40 | D | 0 | $138K |
Recommended Buyer Guides for Sheridan County
Federal and certification sources drive the ordering: EPA monitoring data, NSF certifications, FEMA flood maps, and CDC lead guidance — guides surface only when county data warrants them.
- Best Lead Paint Test Kits — 74.1% of homes built before 1978
- Best Radon Test Kits — EPA Radon Zone 1 (highest risk) dominant in county
Deep Dive Reports
Detailed analysis for Sheridan County, Montana
Overview
Sheridan County in Montana covers 9 ZIP codes with an average Home Safety Score of D (52/100).
3 of 9 ZIP codes have recorded EPA violations. All violations are monitoring/reporting type.
← Back to Montana 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
Sheridan 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
74.1% of homes in this county were built before 1978. Older plumbing and solder can leach lead into drinking water, especially in the morning.