Middlesex County, New Jersey
45 ZIP codes · Avg score 62/100 · Grade C · Updated 2026-06-03
Across Middlesex County's 45 ZIP codes, water safety results are uneven — a portion of systems carry active or recent violations, while others meet standards without issues.
How Middlesex County Compares
How Middlesex County Compares
Middlesex County scores 4 points above the New Jersey state average (58/100) and 6 points below the national average (68/100).
Data: EPA SDWIS Last verified: 2026-06-03
ZIP Code Risk Map
Water Quality Map: Middlesex 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: 10.7 (asthma 8.4%, diabetes 11.4%)
Estimated additional annual cost per homeowner: $5,049, driven primarily by sea_level
Infrastructure: 0.431% avg pipe failure probability, 55% of ZIPs at high risk
72.4% of homes built before 1978 (lead paint era)
Violation History (2021–2026)
↑ Worsening trendEPA violation counts by year across Middlesex County water systems. Health-based shown in red, total in blue.
Peak year: 2025 with 18 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
Sources: Census ACS (housing age), EPA SDWIS (infrastructure risk model), state bridge inspection data.
Compound Risk Breakdown
Estimated additional annual cost per homeowner: $5,049
Bar widths proportional to share of total annual risk cost. Source: compound risk model (FEMA, EPA, USGS).
Housing Age Distribution
300,220 housing units in Middlesex 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 Middlesex County
Remediation costs are relatively manageable for most homeowners in Middlesex 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 Middlesex 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 Middlesex County ranked by EPA violation count.
| # | Water System | Population | Violations |
|---|---|---|---|
| 1 | NEW BRUNSWICK W DEPT | 55,000 | 88 |
| 2 | North Brunswick W Department | 43,905 | 32 |
| 3 | EDISON WATER CO | 35,000 | 30 |
| 4 | MIDDLESEX WATER COMPANY | 233,376 | 30 |
| 5 | Milltown W Department | 7,000 | 21 |
16 total water systems serve Middlesex County.
All ZIP Codes in Middlesex County
45 ZIP codes tracked in Middlesex County.
| # | ZIP Code | City | Safety Score | Grade | Violations | Home Value |
|---|---|---|---|---|---|---|
| 1 | 8862 | Perth Amboy | 78 | B | 3 (1 health) | — |
| 2 | 8871 | Sayreville | 78 | B | 5 | — |
| 3 | 8852 | Monmouth Junction | 77 | B | 4 (1 health) | $489K |
| 4 | 8903 | New Brunswick | 75 | B | 11 | — |
| 5 | 8905 | New Brunswick | 75 | B | 11 | — |
| 6 | 8906 | New Brunswick | 75 | B | 11 | — |
| 7 | 8922 | New Brunswick | 75 | B | 11 | — |
| 8 | 8933 | New Brunswick | 75 | B | 11 | — |
| 9 | 8988 | New Brunswick | 75 | B | 11 | — |
| 10 | 8989 | New Brunswick | 75 | B | 11 | — |
| 11 | 8818 | Edison | 74 | B | 6 | — |
| 12 | 8861 | Perth Amboy | 74 | B | 3 (1 health) | $341K |
| 13 | 8899 | Edison | 74 | B | 6 | — |
| 14 | 8904 | Highland Park | 73 | B | 1 | $464K |
| 15 | 8828 | Helmetta | 71 | B | 2 | $321K |
| 16 | 8837 | Edison | 69 | C | 6 | $433K |
| 17 | 8831 | Monroe Township | 66 | C | 5 | $490K |
| 18 | 8830 | Iselin | 65 | C | 9 | $394K |
| 19 | 8857 | Old Bridge | 65 | C | 4 | $459K |
| 20 | 8901 | New Brunswick | 65 | C | 11 | $317K |
| 21 | 8817 | Edison | 64 | C | 6 | $411K |
| 22 | 8820 | Edison | 64 | C | 6 | $598K |
| 23 | 8884 | Spotswood | 64 | C | 6 | $358K |
| 24 | 8832 | Keasbey | 63 | C | 0 | $328K |
| 25 | 8859 | Parlin | 63 | C | 0 | $407K |
| 26 | 8863 | Fords | 63 | C | 0 | $414K |
| 27 | 8872 | Sayreville | 63 | C | 5 | $404K |
| 28 | 8850 | Milltown | 56 | C | 21 (7 health) | $437K |
| 29 | 7069 | Watchung | 55 | C | 0 | $838K |
| 30 | 8512 | Cranbury | 55 | C | 0 | $618K |
| 31 | 8823 | Franklin Park | 55 | C | 0 | $279K |
| 32 | 8840 | Metuchen | 55 | C | 0 | $518K |
| 33 | 8902 | North Brunswick | 55 | C | 0 | $402K |
| 34 | 8855 | Piscataway | 53 | D | 0 | — |
| 35 | 7077 | Sewaren | 50 | D | 0 | $415K |
| 36 | 8816 | East Brunswick | 50 | D | 0 | $503K |
| 37 | 8879 | South Amboy | 50 | D | 0 | $378K |
| 38 | 8882 | South River | 47 | D | 20 (6 health) | $383K |
| 39 | 7060 | Plainfield | 45 | D | 0 | $369K |
| 40 | 7062 | Plainfield | 45 | D | 0 | $374K |
| 41 | 7063 | Plainfield | 45 | D | 0 | $363K |
| 42 | 7067 | Colonia | 45 | D | 0 | $473K |
| 43 | 7080 | South Plainfield | 45 | D | 0 | $444K |
| 44 | 7095 | Woodbridge | 45 | D | 0 | $361K |
| 45 | 8854 | Piscataway | 45 | D | 0 | $424K |
Recommended Buyer Guides for Middlesex 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 — 72.4% of homes built before 1978
- Best Under-Sink Reverse Osmosis Systems — Multi-contaminant removal at the kitchen tap
Deep Dive Reports
Detailed analysis for Middlesex County, New Jersey
Overview
Middlesex County in New Jersey covers 45 ZIP codes with an average Home Safety Score of C (62/100).
26 of 45 ZIP codes have recorded EPA violations. 16 health-based violations 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.