Twin Falls County, Idaho
9 ZIP codes · Avg score 76/100 · Grade B · Updated 2026-06-04
Twin Falls County earns a high water safety grade — 9 ZIP codes tracked, virtually all compliant.
How Twin Falls County Compares
How Twin Falls County Compares
Twin Falls County scores 10 points above the Idaho state average (66/100) and 8 points above the national average (68/100).
Data: EPA SDWIS Last verified: 2026-06-04
ZIP Code Risk Map
Water Quality Map: Twin Falls 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 11.1%, diabetes 11%)
Estimated additional annual cost per homeowner: $882, driven primarily by energy_code_gap
Infrastructure: 0.384% avg pipe failure probability, 44% of ZIPs at high risk
59.8% of homes built before 1978 (lead paint era)
Violation History (2021–2025)
→ Stable trendEPA violation counts by year across Twin Falls County water systems. Health-based shown in red, total in blue.
Peak year: 2022 with 4 violations. Past 5 years: 13 total (13 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: $882
Bar widths proportional to share of total annual risk cost. Source: compound risk model (FEMA, EPA, USGS).
Housing Age Distribution
35,224 housing units in Twin Falls 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 Twin Falls County
Remediation costs are relatively manageable for most homeowners in Twin Falls 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 Twin Falls 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 Twin Falls County ranked by EPA violation count.
| # | Water System | Population | Violations |
|---|---|---|---|
| 1 | City of Twin Falls | 56,121 | 71 |
| 2 | Filer Water Works | 2,858 | 61 |
| 3 | City of Buhl | 4,518 | 39 |
| 4 | Kanaka Rapids Ranch Water System Inc. | 220 | 39 |
| 5 | Clear Lake Ranch P U D | 54 | 39 |
14 total water systems serve Twin Falls County.
All ZIP Codes in Twin Falls County
9 ZIP codes tracked in Twin Falls County.
| # | ZIP Code | City | Safety Score | Grade | Violations | Home Value |
|---|---|---|---|---|---|---|
| 1 | 83302 | Rogerson | 83 | B | 0 | $140K |
| 2 | 83334 | Hansen | 82 | B | 5 (1 health) | $228K |
| 3 | 83321 | Castleford | 81 | B | 1 | $200K |
| 4 | 83328 | Filer | 81 | B | 12 (2 health) | $294K |
| 5 | 83341 | Kimberly | 80 | B | 3 | $412K |
| 6 | 83316 | Buhl | 77 | B | 39 (2 health) | $248K |
| 7 | 83303 | Twin Falls | 72 | B | 10 (3 health) | — |
| 8 | 83301 | Twin Falls | 69 | C | 10 (3 health) | $291K |
| 9 | 83344 | Murtaugh | 55 | C | 3 (1 health) | $323K |
Recommended Buyer Guides for Twin Falls County
Below: editorial picks, no sponsored placements.
- Best Lead Paint Test Kits — 59.8% of homes built before 1978
- Best Under-Sink Reverse Osmosis Systems — Multi-contaminant removal at the kitchen tap
Deep Dive Reports
Detailed analysis for Twin Falls County, Idaho
Overview
Twin Falls County in Idaho covers 9 ZIP codes with an average Home Safety Score of B (76/100).
8 of 9 ZIP codes have recorded EPA violations. 12 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.