Jefferson County, Iowa
6 ZIP codes · Avg score 60/100 · Grade C · Updated 2026-06-03
Within Jefferson County, 6 tracked ZIP codes reveal moderate water quality — national standards are generally met, with some documented exceptions.
How Jefferson County Compares
How Jefferson County Compares
Jefferson County scores 1 points above the Iowa state average (59/100) and 8 points below the national average (68/100).
Data: EPA SDWIS Last verified: 2026-06-03
ZIP Code Risk Map
Water Quality Map: Jefferson County, Iowa
Each dot represents a ZIP code. Color indicates water quality grade. Tap a dot for details.
Key Risk Factors
Health risk index: 14.3 (asthma 9.6%, diabetes 13.2%)
Estimated additional annual cost per homeowner: $392, driven primarily by energy_code_gap
Infrastructure: 0.465% avg pipe failure probability, 83% of ZIPs at high risk
71.2% 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: $392
Bar widths proportional to share of total annual risk cost. Source: compound risk model (FEMA, EPA, USGS).
Housing Age Distribution
7,711 housing units in Jefferson 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 Jefferson County
Remediation costs are relatively manageable for most homeowners in Jefferson 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 Jefferson 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 Jefferson County ranked by EPA violation count.
| # | Water System | Population | Violations |
|---|---|---|---|
| 1 | Rathbun Regional Water Assn (rathbun) | 33,000 | 15 |
| 2 | Libertyville Water Works | 274 | 10 |
| 3 | Fairfield Water Supply | 9,821 | 10 |
| 4 | Jefferson County Rural Water District | 468 | 10 |
| 5 | Fairfield Estates Mobile Home Park | 140 | 10 |
10 total water systems serve Jefferson County.
All ZIP Codes in Jefferson County
6 ZIP codes tracked in Jefferson County.
| # | ZIP Code | City | Safety Score | Grade | Violations | Home Value |
|---|---|---|---|---|---|---|
| 1 | 52567 | Libertyville | 63 | C | 3 | $179K |
| 2 | 52540 | Brighton | 62 | C | 5 | $107K |
| 3 | 52556 | Fairfield | 61 | C | 5 | $168K |
| 4 | 52557 | Fairfield | 61 | C | 5 | — |
| 5 | 52533 | Batavia | 60 | C | 7 | $110K |
| 6 | 52635 | Lockridge | 55 | C | 0 | — |
Recommended Buyer Guides for Jefferson County
Methodologically, the recommendation order reflects severity in the federal record: contaminants flagged in EPA detection records for this county outrank generic water concerns, FEMA-confirmed hazard ratings shift emergency-related categories upward, and CDC lead-exposure markers govern when lead-test kits and certified filters appear at the top of the list.
- Best Lead Paint Test Kits — 71.2% of homes built before 1978
- Best Radon Test Kits — EPA Radon Zone 1 (highest risk) dominant in county
Deep Dive Reports
Detailed analysis for Jefferson County, Iowa
Overview
Jefferson County in Iowa covers 6 ZIP codes with an average Home Safety Score of C (60/100).
5 of 6 ZIP codes have recorded EPA violations. All violations are monitoring/reporting type.
← 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.