Woodbury County, Iowa
25 ZIP codes · Avg score 64/100 · Grade C · Updated 2026-06-04
Across Woodbury County's 25 ZIP codes, water safety results are uneven — a portion of systems carry active or recent violations, while others meet standards without issues.
How Woodbury County Compares
How Woodbury County Compares
Woodbury County scores 5 points above the Iowa state average (59/100) and 4 points below the national average (68/100).
Data: EPA SDWIS Last verified: 2026-06-04
ZIP Code Risk Map
Water Quality Map: Woodbury County, Iowa
Each dot represents a ZIP code. Color indicates water quality grade. Tap a dot for details.
Key Risk Factors
Health risk index: 13.4 (asthma 9.8%, diabetes 12.1%)
Estimated additional annual cost per homeowner: $1,121, driven primarily by flood
Infrastructure: 0.481% avg pipe failure probability, 92% of ZIPs at high risk
78.7% 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: $1,121
Bar widths proportional to share of total annual risk cost. Source: compound risk model (FEMA, EPA, USGS).
Housing Age Distribution
43,957 housing units in Woodbury 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 Woodbury County
Remediation costs are relatively manageable for most homeowners in Woodbury 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 Woodbury 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 Woodbury County ranked by EPA violation count.
| # | Water System | Population | Violations |
|---|---|---|---|
| 1 | Sioux City Water Supply | 85,791 | 11 |
| 2 | Berea Heights Inc. | 33 | 9 |
| 3 | Oto Water Supply | 72 | 3 |
| 4 | Lawton Water Supply | 943 | 2 |
| 5 | Danbury Water Supply | 320 | 1 |
18 total water systems serve Woodbury County.
All ZIP Codes in Woodbury County
25 ZIP codes tracked in Woodbury County.
| # | ZIP Code | City | Safety Score | Grade | Violations | Home Value |
|---|---|---|---|---|---|---|
| 1 | 51004 | Anthon | 70 | B | 0 | $101K |
| 2 | 51028 | Kingsley | 70 | B | 0 | $195K |
| 3 | 51054 | Sergeant Bluff | 70 | B | 0 | $293K |
| 4 | 51101 | Sioux City | 70 | B | 1 | — |
| 5 | 51102 | Sioux City | 70 | B | 1 | — |
| 6 | 51105 | Sioux City | 70 | B | 1 | $85K |
| 7 | 51108 | Sioux City | 70 | B | 1 | $167K |
| 8 | 51030 | Lawton | 69 | C | 2 | $268K |
| 9 | 51007 | Bronson | 66 | C | 0 | $228K |
| 10 | 51018 | Cushing | 66 | C | 0 | $313K |
| 11 | 51039 | Moville | 66 | C | 0 | $227K |
| 12 | 51048 | Pierson | 66 | C | 0 | $105K |
| 13 | 51052 | Salix | 66 | C | 0 | $236K |
| 14 | 51056 | Smithland | 66 | C | 0 | $151K |
| 15 | 51111 | Sioux City | 66 | C | 1 | — |
| 16 | 51016 | Correctionville | 65 | C | 0 | $88K |
| 17 | 51019 | Danbury | 65 | C | 1 (1 health) | $88K |
| 18 | 51026 | Hornick | 65 | C | 0 | $233K |
| 19 | 51044 | Oto | 65 | C | 3 | $84K |
| 20 | 51106 | Sioux City | 65 | C | 1 | $186K |
| 21 | 51109 | Sioux City | 65 | C | 1 | $120K |
| 22 | 51103 | Sioux City | 60 | C | 1 | $124K |
| 23 | 51104 | Sioux City | 60 | C | 1 | $193K |
| 24 | 51015 | Climbing Hill | 40 | D | 0 | $125K |
| 25 | 51051 | Rodney | 40 | D | 0 | $163K |
Recommended Buyer Guides for Woodbury County
Filtered against EPA monitoring data and CDC lead-exposure guidance, the guides below skip the generic catalog and connect directly to the contaminants and hazards on file here.
- Best Lead Paint Test Kits — 78.7% of homes built before 1978
- 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 Woodbury County, Iowa
Overview
Woodbury County in Iowa covers 25 ZIP codes with an average Home Safety Score of C (64/100).
12 of 25 ZIP codes have recorded EPA violations. 1 health-based violation have been documented.
← Back to Iowa 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.