Warren County, New Jersey
21 ZIP codes · Avg score 46/100 · Grade D · Updated 2026-07-19
ZipCheckup grade for Warren: D.
Several federal signals point to home-safety risks in this ZIP.
Your top priority: see the breakdown below and consider a certified water filter. NSF certified filters →
Water safety in Warren County ranks low - 21 ZIP codes, persistent health-based violations on record.
How Warren County Compares
How Warren County Compares
Warren County scores 12 points below the New Jersey state average (58/100) and 22 points below the national average (68/100).
Data: EPA SDWIS Last verified: 2026-07-19
ZIP Code Risk Map
Water Quality Map: Warren County, New Jersey
Each dot represents a ZIP code. Color indicates water quality grade. Tap a dot for details.
Key Risk Factors
Health risk index: 11.7 (asthma 9.2%, diabetes 10.7%)
Estimated additional annual cost per homeowner: $3,734, driven primarily by flood
Infrastructure: 0.548% avg pipe failure probability, 63% of ZIPs at high risk
78.5% of homes built before 1978 (lead paint era)
Violation History (2021–2024)
→ Stable trendEPA violation counts by year across Warren County water systems. Health-based shown in red, total in blue.
Peak year: 2024 with 4 violations. Past 5 years: 8 total (8 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: $3,734
Bar widths proportional to share of total annual risk cost. Source: compound risk model (FEMA, EPA, USGS).
Housing Age Distribution
86,633 housing units in Warren 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 Warren County
Remediation costs are relatively manageable for most homeowners in Warren 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 Warren County residents
Black markers = national averages. Red = above national avg. Green = below. Source: CDC PLACES, Census ACS.
Water systems serving Warren County
8 community water systems serving Warren County.
- C
- C
- C
- D
- D
- D
Show all 8 water systems
- F
- D
17 total water systems serve Warren County.
Systems with the most violations in Warren County
5 water systems with recorded EPA violations.
- C
- C
- C
- D
- D
All ZIP Codes in Warren County
21 ZIP codes tracked in Warren County.
| # | ZIP Code | City | Safety Score | Grade | Violations | Home Value |
|---|---|---|---|---|---|---|
| 1 | 07820 | Allamuchy | 65 | C | 8 (1 health) | — |
| 2 | 07844 | Hope | 62 | C | 5 | — |
| 3 | 07882 | Washington | 60 | C | 0 | $334K |
| 4 | 07829 | Buttzville | 53 | D | 0 | — |
| 5 | 07833 | Delaware | 53 | D | 0 | $220K |
| 6 | 07838 | Great Meadows | 53 | D | 0 | $410K |
| 7 | 07832 | Columbia | 52 | D | 4 | $326K |
| 8 | 07840 | Hackettstown | 51 | D | 15 | $373K |
| 9 | 08865 | Phillipsburg | 51 | D | 3 | $244K |
| 10 | 07023 | Fanwood | 45 | D | 0 | $611K |
| 11 | 07061 | Plainfield | 45 | D | 0 | — |
| 12 | 07027 | Garwood | 40 | D | 0 | $510K |
| 13 | 07033 | Kenilworth | 40 | D | 0 | $521K |
| 14 | 07090 | Westfield | 40 | D | 0 | $931K |
| 15 | 07091 | Westfield | 40 | D | 0 | — |
| 16 | 07204 | Roselle Park | 40 | D | 0 | $406K |
| 17 | 07825 | Blairstown | 40 | D | 0 | $411K |
| 18 | 07076 | Scotch Plains | 35 | F | 0 | $697K |
| 19 | 07203 | Roselle | 35 | F | 0 | $337K |
| 20 | 07823 | Belvidere | 35 | F | 0 | $315K |
| 21 | 07863 | Oxford | 34 | F | 4 | $276K |
Recommended Buyer Guides for Warren 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 Water Filters for Lead — Lead above EPA action level in 1 ZIP code
- Best Lead Paint Test Kits — 78.5% of homes built before 1978
- Best Under-Sink Reverse Osmosis Systems — Multi-contaminant removal at the kitchen tap
- Best Radon Test Kits — EPA Radon Zone 1 (highest risk) dominant in county
- Best Sump Pumps — Flood is the top compound risk factor
Deep Dive Reports
Detailed analysis for Warren County, New Jersey
Overview
Warren County in New Jersey covers 21 ZIP codes with an average Home Safety Score of D (46/100).
6 of 21 ZIP codes have recorded EPA violations. 1 health-based violation have been documented.
← Back to New Jersey 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.
What You Can Do
Warren County has a grade of D. Here are steps to protect your household.
Test your tap water
Order a certified lab test kit ($20-$50) to check for lead, bacteria, and other contaminants specific to your ZIP code.
Consider a certified water filter
NSF-certified filters can remove most common contaminants. Match the filter to your test results for best protection. Try our filter matcher
Contact your water utility
Request the latest Consumer Confidence Report (CCR) from your water provider. It details exactly what was found in your water supply.
Check for lead in your home
78.5% of homes in this county were built before 1978. Older plumbing and solder can leach lead into drinking water, especially in the morning.