Monmouth County, New Jersey
50 ZIP codes · Avg score 44/100 · Grade D · Updated 2026-06-03
Across Monmouth County, EPA compliance records for 50 ZIP codes fall well below average — documented health-based violations affect multiple areas, and the county's sustained low grade points to structural rather than temporary shortfalls in the underlying water systems.
How Monmouth County Compares
How Monmouth County Compares
Monmouth County scores 14 points below the New Jersey state average (58/100) and 24 points below the national average (68/100).
Data: EPA SDWIS Last verified: 2026-06-03
ZIP Code Risk Map
Water Quality Map: Monmouth 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: 11.2 (asthma 8.8%, diabetes 9.9%)
Estimated additional annual cost per homeowner: $5,669, driven primarily by sea_level
Infrastructure: 0.443% avg pipe failure probability, 82% of ZIPs at high risk
71% of homes built before 1978 (lead paint era)
Violation History (2021–2025)
↑ Worsening trendEPA violation counts by year across Monmouth County water systems. Health-based shown in red, total in blue.
Peak year: 2023 with 14 violations. Past 5 years: 23 total (23 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: $5,669
Bar widths proportional to share of total annual risk cost. Source: compound risk model (FEMA, EPA, USGS).
Housing Age Distribution
263,017 housing units in Monmouth 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 Monmouth County
Remediation costs are relatively manageable for most homeowners in Monmouth 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 Monmouth 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 Monmouth County ranked by EPA violation count.
| # | Water System | Population | Violations |
|---|---|---|---|
| 1 | Nj American Water - Coastal North | 377,613 | 30 |
| 2 | KEANSBURG WATER & SEWER DEPT. | 10,105 | 27 |
| 3 | Keyport Water Department | 7,500 | 27 |
| 4 | FREEHOLD TWP WATER DEPT | 29,831 | 21 |
| 5 | BELMAR WATER DEPT | 20,000 | 20 |
24 total water systems serve Monmouth County.
All ZIP Codes in Monmouth County
50 ZIP codes tracked in Monmouth County.
| # | ZIP Code | City | Safety Score | Grade | Violations | Home Value |
|---|---|---|---|---|---|---|
| 1 | 7715 | Belmar | 69 | C | 10 (1 health) | — |
| 2 | 7727 | Farmingdale | 64 | C | 3 | $586K |
| 3 | 7747 | Matawan | 64 | C | 2 (1 health) | $464K |
| 4 | 7722 | Colts Neck | 63 | C | 1 | $871K |
| 5 | 7731 | Howell | 63 | C | 1 | $455K |
| 6 | 7746 | Marlboro | 61 | C | 6 | $655K |
| 7 | 7716 | Atlantic Highlands | 60 | C | 1 | $622K |
| 8 | 7728 | Freehold | 56 | C | 18 (1 health) | $490K |
| 9 | 7719 | Belmar | 54 | D | 10 (1 health) | $629K |
| 10 | 7726 | Englishtown | 54 | D | 3 | $603K |
| 11 | 7752 | Navesink | 53 | D | 0 | — |
| 12 | 7754 | Neptune | 53 | D | 0 | — |
| 13 | 7763 | Tennent | 53 | D | 0 | — |
| 14 | 8730 | Brielle | 51 | D | 5 | $815K |
| 15 | 7734 | Keansburg | 46 | D | 27 (1 health) | $310K |
| 16 | 7702 | Shrewsbury | 45 | D | 0 | $736K |
| 17 | 7704 | Fair Haven | 45 | D | 0 | $943K |
| 18 | 7724 | Eatontown | 45 | D | 0 | $487K |
| 19 | 7738 | Lincroft | 45 | D | 0 | $719K |
| 20 | 7751 | Morganville | 45 | D | 0 | $663K |
| 21 | 7764 | West Long Branch | 45 | D | 0 | $631K |
| 22 | 7701 | Red Bank | 40 | D | 0 | $552K |
| 23 | 7703 | Fort Monmouth | 40 | D | 0 | — |
| 24 | 7710 | Adelphia | 40 | D | 0 | — |
| 25 | 7711 | Allenhurst | 40 | D | 0 | $1076K |
| 26 | 7712 | Asbury Park | 40 | D | 0 | $578K |
| 27 | 7720 | Bradley Beach | 40 | D | 0 | $857K |
| 28 | 7723 | Deal | 40 | D | 0 | $1342K |
| 29 | 7730 | Hazlet | 40 | D | 0 | $453K |
| 30 | 7737 | Leonardo | 40 | D | 0 | $469K |
| 31 | 7755 | Oakhurst | 40 | D | 0 | $655K |
| 32 | 7756 | Ocean Grove | 40 | D | 0 | $764K |
| 33 | 7765 | Wickatunk | 40 | D | 0 | — |
| 34 | 7799 | Eatontown | 40 | D | 0 | — |
| 35 | 8720 | Allenwood | 40 | D | 0 | $757K |
| 36 | 8750 | Sea Girt | 40 | D | 0 | $1118K |
| 37 | 7732 | Highlands | 36 | F | 4 (2 health) | $397K |
| 38 | 7717 | Avon By The Sea | 35 | F | 0 | $1349K |
| 39 | 7718 | Belford | 35 | F | 0 | $490K |
| 40 | 7739 | Little Silver | 35 | F | 0 | $871K |
| 41 | 7748 | Middletown | 35 | F | 0 | $568K |
| 42 | 7753 | Neptune | 35 | F | 0 | $391K |
| 43 | 7757 | Oceanport | 35 | F | 0 | $686K |
| 44 | 7758 | Port Monmouth | 35 | F | 0 | $479K |
| 45 | 7762 | Spring Lake | 35 | F | 0 | $871K |
| 46 | 7740 | Long Branch | 30 | F | 0 | $522K |
| 47 | 7750 | Monmouth Beach | 30 | F | 0 | $918K |
| 48 | 7760 | Rumson | 30 | F | 0 | $1275K |
| 49 | 8736 | Manasquan | 30 | F | 0 | $850K |
| 50 | 8742 | Point Pleasant Beach | 30 | F | 0 | $576K |
Recommended Buyer Guides for Monmouth 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 — 71% 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 Monmouth County, New Jersey
Overview
Monmouth County in New Jersey covers 50 ZIP codes with an average Home Safety Score of D (44/100).
13 of 50 ZIP codes have recorded EPA violations. 7 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
Monmouth 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
71% of homes in this county were built before 1978. Older plumbing and solder can leach lead into drinking water, especially in the morning.