Johnston County, North Carolina
13 ZIP codes · Avg score 73/100 · Grade B · Updated
ZipCheckup grade for Johnston County: B.
This ZIP looks solid, with a few items worth a quick check.
In current tracking cycles, Johnston County - spanning 13 ZIP codes - records above-average water quality outcomes; the county's compliance history over recent years shows few departures from federal standards.
How Johnston County Compares
How Johnston County Compares
Johnston County scores 5 points below the North Carolina state average (78/100) and 0 points above the national average (73/100).
Data: ZipCheckup Home Safety Score model 4.0.0; EPA SDWIS, UCMR 5, EPA radon zones, EPA AirData Last verified:
ZIP Code Risk Map
Water Quality Map: Johnston County, North Carolina
Each dot represents a ZIP code. Color indicates water quality grade. Tap a dot for details.
Key Risk Factors
Health risk index: 12.6 (asthma 10.8%, diabetes 11.6%)
Estimated additional annual cost per homeowner: $1,397, driven primarily by flood
40.3% of homes built before 1978 (lead paint era)
Violation History (2022–2025)
↑ Worsening trendEPA violation counts by year across Johnston County water systems. Health-based shown in red, total in blue.
Peak year: 2024 with 23 violations. Past 5 years: 34 total (34 health-based). Health-based violations are rising versus the prior 2-year window - worth closer monitoring.
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
Modeled area-level indicator, not a failure probability. Sources: Census ACS housing age, EPA DWINS infrastructure needs, EPA SDWIS violations, and EPA lead indicators.
Compound Risk Breakdown
Estimated additional annual cost per homeowner: $1,397
Bar widths proportional to share of total annual risk cost. Source: compound risk model (FEMA, EPA, USGS).
Housing Age Distribution
76,641 housing units in Johnston 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 Johnston County
Remediation costs are relatively manageable for most homeowners in Johnston 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 Johnston County residents
Black markers = national averages. Red = above national avg. Green = below. Source: CDC PLACES, Census ACS.
Water systems serving Johnston County
8 community water systems serving Johnston County.
- B
- C
- C
- C
- B
- C
Show all 8 water systems
- C
- B
27 total water systems serve Johnston County.
Systems with the most violations in Johnston County
5 water systems with recorded EPA violations.
- C
- C
- B
- B
- B
All ZIP Codes in Johnston County
13 ZIP codes tracked in Johnston County.
| # | ZIP Code | City | Safety Score | Grade | Violations | Home Value |
|---|---|---|---|---|---|---|
| 1 | 27504 | Benson | 82 | B | 3 | $217K |
| 2 | 27527 | Clayton | 81 | B | 8 | $361K |
| 3 | 27520 | Clayton | 75 | B | 24 (2 health) | $282K |
| 4 | 27576 | Selma | 73 | B | 23 (3 health) | $178K |
| 5 | 27524 | Four Oaks | 72 | B | 28 (6 health) | $211K |
| 6 | 27542 | Kenly | 71 | B | 25 (9 health) | $181K |
| 7 | 27569 | Princeton | 67 | C | 26 (4 health) | $194K |
| 8 | 27577 | Smithfield | 67 | C | 36 (4 health) | $230K |
| 9 | 27592 | Willow Spring | 67 | C | 167 (1 health) | $335K |
| 10 | 27528 | Clayton | — | — | — | |
| 11 | 27555 | Micro | — | — | $213K | |
| 12 | 27568 | Pine Level | — | — | 4 (1 health) | $233K |
| 13 | 27593 | Wilsons Mills | — | — | 2 | — |
Recommended Buyer Guides for Johnston County
Four sources - EPA, NSF, FEMA, CDC - drive the match.
- Best Water Filters for PFAS — PFAS detected in 1 ZIP code
- Best Under-Sink Reverse Osmosis Systems — Multi-contaminant removal at the kitchen tap
- 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 Johnston County, North Carolina
Overview
Johnston County in North Carolina covers 13 tracked ZIP records with an average Home Safety Score of B (73/100) across 9 scored records.
11 of 11 ZIP codes with a reported violation count in the available EPA record have recorded EPA violations. 20 health-based violations appear in the available health breakdown.
← Back to North Carolina Home Safety Profile
Data Sources
- Water quality: EPA Safe Drinking Water Information System (SDWIS)
- PFAS screening: EPA UCMR 5
- Radon zones: EPA Map of Radon Zones
- Air quality: EPA AirData annual AQI
- Home values: U.S. Census Bureau ACS (median estimates by ZCTA)
Reporting periods vary by source. Missing data is shown as unavailable, not as zero.