Johnson County, Arkansas
8 ZIP codes · Avg score 82/100 · Grade B · Updated 2026-06-03
Water systems in Johnson County serve 8 ZIP codes with few reported safety events.
How Johnson County Compares
How Johnson County Compares
Johnson County scores 6 points above the Arkansas state average (76/100) and 14 points above the national average (68/100).
Data: EPA SDWIS Last verified: 2026-06-03
ZIP Code Risk Map
Water Quality Map: Johnson County, Arkansas
Each dot represents a ZIP code. Color indicates water quality grade. Tap a dot for details.
Key Risk Factors
Health risk index: 15.3 (asthma 10.3%, diabetes 14.6%)
Estimated additional annual cost per homeowner: $509, driven primarily by wildfire
Infrastructure: 0.32% avg pipe failure probability
54.8% 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: $509
Bar widths proportional to share of total annual risk cost. Source: compound risk model (FEMA, EPA, USGS).
Housing Age Distribution
11,052 housing units in Johnson 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 Johnson County
Remediation costs are relatively manageable for most homeowners in Johnson 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 Johnson 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 Johnson County ranked by EPA violation count.
| # | Water System | Population | Violations |
|---|---|---|---|
| 1 | Horsehead Water Association | 5,792 | 5 |
| 2 | Coal Hill Waterworks | 1,372 | 5 |
| 3 | Clarksville Connected Utilities | 9,410 | 3 |
| 4 | Ludwig Water Association | 1,610 | 3 |
| 5 | Spadra-goose Camp Water Assoc | 517 | 3 |
9 total water systems serve Johnson County.
All ZIP Codes in Johnson County
8 ZIP codes tracked in Johnson County.
| # | ZIP Code | City | Safety Score | Grade | Violations | Home Value |
|---|---|---|---|---|---|---|
| 1 | 72846 | Lamar | 99 | A | 0 | $136K |
| 2 | 72830 | Clarksville | 94 | A | 3 | $150K |
| 3 | 72845 | Knoxville | 88 | A | 0 | $100K |
| 4 | 72832 | Coal Hill | 87 | A | 2 | $84K |
| 5 | 72840 | Hartman | 87 | A | 0 | $93K |
| 6 | 72839 | Hagarville | 66 | C | 0 | $54K |
| 7 | 72852 | Oark | 66 | C | 0 | $119K |
| 8 | 72854 | Ozone | 66 | C | 0 | $99K |
Recommended Buyer Guides for Johnson County
Designed to find the guide that fits the county, not the other way around — the system reads EPA detections, FEMA hazard layers, and CDC lead-exposure markers, then outputs the categories that resolve those specific risks for households here, with NSF-certified products surfaced when the matching contaminant appears in the local monitoring data.
- Best Lead Paint Test Kits — 54.8% of homes built before 1978
- Best HEPA Air Purifiers for Wildfire Smoke — Wildfire is the top compound risk factor
Deep Dive Reports
Detailed analysis for Johnson County, Arkansas
Overview
Johnson County in Arkansas covers 8 ZIP codes with an average Home Safety Score of B (82/100).
2 of 8 ZIP codes have recorded EPA violations. All violations are monitoring/reporting type.
← Back to Arkansas 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.