Mercer County, New Jersey
47 ZIP codes · Avg score 52/100 · Grade D · Updated 2026-07-19
ZipCheckup grade for Mercer: D.
Several federal signals point to home-safety risks in this ZIP.
Across Mercer County's 47 ZIP codes, EPA data shows a below-average compliance pattern - health-based violations are documented in several areas, and independent testing is a reasonable step for concerned households.
How Mercer County Compares
How Mercer County Compares
Mercer County scores 6 points below the New Jersey state average (58/100) and 16 points below the national average (68/100).
Data: EPA SDWIS Last verified: 2026-07-19
ZIP Code Risk Map
Water Quality Map: Mercer 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: 10.6 (asthma 8.9%, diabetes 10.9%)
Estimated additional annual cost per homeowner: $4,844, driven primarily by sea_level
Infrastructure: 0.503% avg pipe failure probability, 79% of ZIPs at high risk
63.5% of homes built before 1978 (lead paint era)
Violation History (2021–2024)
→ Stable trendEPA violation counts by year across Mercer County water systems. Health-based shown in red, total in blue.
Peak year: 2021 with 86 violations. Past 5 years: 140 total (140 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: $4,844
Bar widths proportional to share of total annual risk cost. Source: compound risk model (FEMA, EPA, USGS).
Housing Age Distribution
151,418 housing units in Mercer 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 Mercer County
Remediation costs are relatively manageable for most homeowners in Mercer 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 Mercer County residents
Black markers = national averages. Red = above national avg. Green = below. Source: CDC PLACES, Census ACS.
Water systems serving Mercer County
6 community water systems serving Mercer County.
- D
- C
- C
- D
- D
- C
Systems with the most violations in Mercer County
3 water systems with recorded EPA violations.
- D
- D
- C
All ZIP Codes in Mercer County
47 ZIP codes tracked in Mercer County.
| # | ZIP Code | City | Safety Score | Grade | Violations | Home Value |
|---|---|---|---|---|---|---|
| 1 | 08525 | Hopewell | 60 | C | 11 (2 health) | $551K |
| 2 | 08604 | Trenton | 60 | C | 51 (4 health) | — |
| 3 | 08608 | Trenton | 60 | C | 51 (4 health) | — |
| 4 | 08620 | Trenton | 60 | C | 51 (4 health) | $341K |
| 5 | 08690 | Trenton | 60 | C | 51 (4 health) | $363K |
| 6 | 08691 | Trenton | 60 | C | 51 (4 health) | $524K |
| 7 | 08534 | Pennington | 59 | C | 4 | $573K |
| 8 | 08560 | Titusville | 57 | C | 5 | $400K |
| 9 | 08609 | Trenton | 55 | C | 51 (4 health) | $97K |
| 10 | 08610 | Trenton | 55 | C | 51 (4 health) | $249K |
| 11 | 08611 | Trenton | 55 | C | 51 (4 health) | $142K |
| 12 | 08629 | Trenton | 55 | C | 51 (4 health) | $149K |
| 13 | 08602 | Trenton | 54 | D | 51 (4 health) | — |
| 14 | 08603 | Trenton | 54 | D | 51 (4 health) | — |
| 15 | 08605 | Trenton | 54 | D | 51 (4 health) | — |
| 16 | 08606 | Trenton | 54 | D | 51 (4 health) | — |
| 17 | 08607 | Trenton | 54 | D | 51 (4 health) | — |
| 18 | 08625 | Trenton | 54 | D | 51 (4 health) | — |
| 19 | 08641 | Trenton | 54 | D | 51 (4 health) | — |
| 20 | 08644 | Trenton | 54 | D | 51 (4 health) | — |
| 21 | 08645 | Trenton | 54 | D | 51 (4 health) | — |
| 22 | 08646 | Trenton | 54 | D | 51 (4 health) | — |
| 23 | 08647 | Trenton | 54 | D | 51 (4 health) | — |
| 24 | 08650 | Trenton | 54 | D | 51 (4 health) | — |
| 25 | 08666 | Trenton | 54 | D | 51 (4 health) | — |
| 26 | 08695 | Trenton | 54 | D | 51 (4 health) | — |
| 27 | 08501 | Allentown | 53 | D | 0 | $530K |
| 28 | 08510 | Millstone Township | 53 | D | 0 | $645K |
| 29 | 08515 | Chesterfield | 53 | D | 0 | $518K |
| 30 | 08535 | Millstone Township | 53 | D | 0 | $684K |
| 31 | 08542 | Princeton | 53 | D | 0 | $755K |
| 32 | 08543 | Princeton | 53 | D | 0 | — |
| 33 | 08544 | Princeton | 53 | D | 0 | — |
| 34 | 08555 | Roosevelt | 53 | D | 0 | $355K |
| 35 | 08561 | Windsor | 53 | D | 0 | $480K |
| 36 | 08628 | Trenton | 50 | D | 51 (4 health) | $358K |
| 37 | 08520 | Hightstown | 45 | D | 0 | $362K |
| 38 | 08550 | Princeton Junction | 45 | D | 0 | $759K |
| 39 | 08551 | Ringoes | 45 | D | 0 | $580K |
| 40 | 08618 | Trenton | 45 | D | 51 (4 health) | $212K |
| 41 | 08619 | Trenton | 45 | D | 51 (4 health) | $321K |
| 42 | 08638 | Trenton | 45 | D | 51 (4 health) | $227K |
| 43 | 08504 | Blawenburg | 40 | D | 0 | — |
| 44 | 08541 | Princeton | 40 | D | 0 | — |
| 45 | 08558 | Skillman | 40 | D | 0 | $853K |
| 46 | 08640 | Fort Dix | 40 | D | 0 | — |
| 47 | 08648 | Lawrence Township | 40 | D | 0 | $395K |
Recommended Buyer Guides for Mercer County
Where county records show a lead exceedance or pre-1978 housing concentration, lead-specific filters and test kits move toward the top of the list.
- Best Lead Paint Test Kits — 63.5% 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
Deep Dive Reports
Detailed analysis for Mercer County, New Jersey
Overview
Mercer County in New Jersey covers 47 ZIP codes with an average Home Safety Score of D (52/100).
30 of 47 ZIP codes have recorded EPA violations. 110 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.
What You Can Do
Mercer 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
63.5% of homes in this county were built before 1978. Older plumbing and solder can leach lead into drinking water, especially in the morning.