Kootenai County, Idaho
15 ZIP codes · Avg score 63/100 · Grade C · Updated 2026-06-04
Water systems across Kootenai County's 15 ZIP codes produce average compliance results overall — pockets with documented violations exist, and the variation between areas makes ZIP-level lookup the most useful tool for residents here.
How Kootenai County Compares
How Kootenai County Compares
Kootenai County scores 3 points below the Idaho state average (66/100) and 5 points below the national average (68/100).
Data: EPA SDWIS Last verified: 2026-06-04
ZIP Code Risk Map
Water Quality Map: Kootenai County, Idaho
Each dot represents a ZIP code. Color indicates water quality grade. Tap a dot for details.
Key Risk Factors
Health risk index: 12.3 (asthma 10.8%, diabetes 10.3%)
Estimated additional annual cost per homeowner: $1,033, driven primarily by flood
Infrastructure: 0.31% avg pipe failure probability, 7% of ZIPs at high risk
45% of homes built before 1978 (lead paint era)
Violation History (2021–2025)
→ Stable trendEPA violation counts by year across Kootenai County water systems. Health-based shown in red, total in blue.
Peak year: 2021 with 4 violations. Past 5 years: 8 total (8 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: $1,033
Bar widths proportional to share of total annual risk cost. Source: compound risk model (FEMA, EPA, USGS).
Housing Age Distribution
79,467 housing units in Kootenai 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 Kootenai County
Remediation costs are relatively manageable for most homeowners in Kootenai 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 Kootenai 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 Kootenai County ranked by EPA violation count.
| # | Water System | Population | Violations |
|---|---|---|---|
| 1 | City of Worley | 591 | 16 |
| 2 | Cave Bay Community System | 458 | 16 |
| 3 | Conkling Park Water Assn | 309 | 16 |
| 4 | Sm Utilities | 58 | 16 |
| 5 | City of Spirit Lake | 2,825 | 5 |
38 total water systems serve Kootenai County.
All ZIP Codes in Kootenai County
15 ZIP codes tracked in Kootenai County.
| # | ZIP Code | City | Safety Score | Grade | Violations | Home Value |
|---|---|---|---|---|---|---|
| 1 | 83815 | Coeur D Alene | 70 | B | 0 | $472K |
| 2 | 83816 | Coeur D Alene | 70 | B | 0 | — |
| 3 | 83877 | Post Falls | 69 | C | 1 (1 health) | — |
| 4 | 83803 | Bayview | 68 | C | 1 | $661K |
| 5 | 83835 | Hayden | 68 | C | 1 | $502K |
| 6 | 83842 | Medimont | 66 | C | 0 | $635K |
| 7 | 83858 | Rathdrum | 66 | C | 2 | $453K |
| 8 | 83814 | Coeur D Alene | 65 | C | 0 | $519K |
| 9 | 83854 | Post Falls | 65 | C | 1 (1 health) | $434K |
| 10 | 83801 | Athol | 64 | C | 1 | $496K |
| 11 | 83833 | Harrison | 64 | C | 2 (1 health) | $530K |
| 12 | 83869 | Spirit Lake | 64 | C | 2 | $425K |
| 13 | 83876 | Worley | 59 | C | 16 (3 health) | $428K |
| 14 | 83861 | Saint Maries | 45 | D | 0 | $273K |
| 15 | 83809 | Careywood | 40 | D | 0 | — |
Recommended Buyer Guides for Kootenai County
While many sites publish identical guide lists across every county they cover, the selection here changes by location — driven by the EPA, NSF, FEMA, and CDC datasets that describe the actual conditions documented for this jurisdiction in the federal record.
- 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 Kootenai County, Idaho
Overview
Kootenai County in Idaho covers 15 ZIP codes with an average Home Safety Score of C (63/100).
9 of 15 ZIP codes have recorded EPA violations. 6 health-based violations have been documented.
← Back to Idaho 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.