Lewis and Clark County, Montana
15 ZIP codes · Avg score 51/100 · Grade D · Updated
ZipCheckup grade for Lewis and Clark County: D.
Several federal signals point to home-safety risks in this ZIP.
Of 15 ZIP codes in Lewis and Clark County, a meaningful portion have recorded health-based violations in recent monitoring periods - placing the county in the lower tier for water safety.
How Lewis and Clark County Compares
How Lewis and Clark County Compares
Lewis and Clark County scores 14 points below the Montana state average (65/100) and 22 points below the national average (73/100).
Data: ZipCheckup Home Safety Score model 4.0.0; EPA SDWIS, UCMR 5, EPA radon zones, EPA AirData Last verified:
ZIP Code Risk Map
Water Quality Map: Lewis and Clark County, Montana
Each dot represents a ZIP code. Color indicates water quality grade. Tap a dot for details.
Key Risk Factors
Health risk index: 11.8 (asthma 11.2%, diabetes 9.3%)
Estimated additional annual cost per homeowner: $1,040, driven primarily by flood
Violation History (2022–2024)
→ Stable trendEPA violation counts by year across Lewis and Clark County water systems. Health-based shown in red, total in blue.
Peak year: 2022 with 13 violations. Past 5 years: 23 total (23 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
Modeled area-level indicator, not a failure probability. Sources: Census ACS housing age, EPA DWINS infrastructure needs, EPA SDWIS violations, and EPA lead indicators.
Compound Risk Breakdown
Estimated additional annual cost per homeowner: $1,040
Bar widths proportional to share of total annual risk cost. Source: compound risk model (FEMA, EPA, USGS).
Water Safety Affordability
How much it costs to fix water issues relative to home values in Lewis and Clark County
Remediation costs are relatively manageable for most homeowners in Lewis and Clark 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 Lewis and Clark County residents
Black markers = national averages. Red = above national avg. Green = below. Source: CDC PLACES, Census ACS.
Water systems serving Lewis and Clark County
8 community water systems serving Lewis and Clark County.
- D
- D
- D
- D
Show all 8 water systems
- D
- D
10 total water systems serve Lewis and Clark County.
Systems with the most violations in Lewis and Clark County
5 water systems with recorded EPA violations.
- D
- D
- D
- D
All ZIP Codes in Lewis and Clark County
15 ZIP codes tracked in Lewis and Clark County.
| # | ZIP Code | City | Safety Score | Grade | Violations | Home Value |
|---|---|---|---|---|---|---|
| 1 | 59601 | Helena | 51 | D | 41 (4 health) | $355K |
| 2 | 59602 | Helena | 50 | D | 133 (5 health) | $370K |
| 3 | 59410 | Augusta | — | — | $228K | |
| 4 | 59604 | Helena | — | — | — | |
| 5 | 59620 | Helena | — | — | — | |
| 6 | 59623 | Helena | — | — | — | |
| 7 | 59624 | Helena | — | — | — | |
| 8 | 59625 | Helena | — | — | 3 (3 health) | — |
| 9 | 59626 | Helena | — | — | — | |
| 10 | 59633 | Canyon Creek | — | — | $410K | |
| 11 | 59635 | East Helena | — | — | 7 (4 health) | $356K |
| 12 | 59636 | Fort Harrison | — | — | — | |
| 13 | 59639 | Lincoln | — | — | $294K | |
| 14 | 59640 | Marysville | — | — | $275K | |
| 15 | 59648 | Wolf Creek | — | — | $321K |
Recommended Buyer Guides for Lewis and Clark 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 Water Filters for PFAS — PFAS detected in 1 ZIP code
- 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 Lewis and Clark County, Montana
Overview
Lewis and Clark County in Montana covers 15 tracked ZIP records with an average Home Safety Score of D (51/100) across 2 scored records.
4 of 4 ZIP codes with a reported violation count in the available EPA record have recorded EPA violations. 5 health-based violations appear in the available health breakdown.
← Back to Montana Home Safety Profile
Data Sources
- Water quality: EPA Safe Drinking Water Information System (SDWIS)
- PFAS screening: EPA UCMR 5
- Radon zones: EPA Map of Radon Zones
- Air quality: EPA AirData annual AQI
- Home values: U.S. Census Bureau ACS (median estimates by ZCTA)
Reporting periods vary by source. Missing data is shown as unavailable, not as zero.
What You Can Do
Lewis and Clark 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.