Middlesex County, Massachusetts
105 ZIP codes · Avg score 58/100 · Grade C · Updated 2026-06-03
Monitoring figures for Middlesex County indicate average water quality overall — some ZIP codes among the 105 tracked have recorded health-based violations, while others operate cleanly, making individual ZIP-level data the most actionable reference point.
How Middlesex County Compares
How Middlesex County Compares
Middlesex County scores 8 points below the Massachusetts state average (66/100) and 10 points below the national average (68/100).
Data: EPA SDWIS Last verified: 2026-06-03
ZIP Code Risk Map
Water Quality Map: Middlesex County, Massachusetts
Each dot represents a ZIP code. Color indicates water quality grade. Tap a dot for details.
Key Risk Factors
Health risk index: 9.9 (asthma 11.1%, diabetes 8.5%)
Estimated additional annual cost per homeowner: $1,836, driven primarily by flood
Infrastructure: 0.433% avg pipe failure probability, 72% of ZIPs at high risk
71.7% of homes built before 1978 (lead paint era)
Violation History (2021–2025)
→ Stable trendEPA violation counts by year across Middlesex County water systems. Health-based shown in red, total in blue.
Peak year: 2023 with 18 violations. Past 5 years: 40 total (40 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: $1,836
Bar widths proportional to share of total annual risk cost. Source: compound risk model (FEMA, EPA, USGS).
Housing Age Distribution
637,750 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 | Brook Village Condominium | 400 | 26 |
| 2 | Harvard Ridge Condominium | 350 | 25 |
| 3 | Codman Hill Condominium | 360 | 24 |
| 4 | Applewood Community Corporation | 500 | 23 |
| 5 | Paddock Estates | 463 | 23 |
92 total water systems serve Middlesex County.
All ZIP Codes in Middlesex County
105 ZIP codes tracked in Middlesex County.
| # | ZIP Code | City | Safety Score | Grade | Violations | Home Value |
|---|---|---|---|---|---|---|
| 1 | 1450 | Groton | 70 | B | 0 | $674K |
| 2 | 1460 | Littleton | 70 | B | 1 | $633K |
| 3 | 1703 | Framingham | 70 | B | 0 | — |
| 4 | 1705 | Framingham | 70 | B | 0 | — |
| 5 | 1741 | Carlisle | 70 | B | 0 | $1056K |
| 6 | 2143 | Somerville | 70 | B | 0 | $930K |
| 7 | 2144 | Somerville | 70 | B | 0 | $987K |
| 8 | 2180 | Stoneham | 70 | B | 0 | $629K |
| 9 | 1754 | Maynard | 69 | C | 2 | $494K |
| 10 | 1775 | Stow | 69 | C | 2 | $658K |
| 11 | 1432 | Ayer | 68 | C | 5 | $420K |
| 12 | 1850 | Lowell | 68 | C | 1 | $367K |
| 13 | 1888 | Woburn | 68 | C | 1 | — |
| 14 | 1770 | Sherborn | 67 | C | 1 | $944K |
| 15 | 1470 | Groton | 66 | C | 0 | — |
| 16 | 1471 | Groton | 66 | C | 0 | — |
| 17 | 1704 | Framingham | 66 | C | 0 | — |
| 18 | 1827 | Dunstable | 66 | C | 0 | $624K |
| 19 | 1889 | North Reading | 66 | C | 0 | — |
| 20 | 1463 | Pepperell | 65 | C | 1 | $460K |
| 21 | 1719 | Boxborough | 65 | C | 23 (1 health) | $672K |
| 22 | 1886 | Westford | 65 | C | 1 | $689K |
| 23 | 2145 | Somerville | 65 | C | 0 | $785K |
| 24 | 2454 | Waltham | 65 | C | 2 | — |
| 25 | 2493 | Weston | 65 | C | 0 | $1586K |
| 26 | 1464 | Shirley | 64 | C | 2 | $413K |
| 27 | 1720 | Acton | 64 | C | 2 | $767K |
| 28 | 1805 | Burlington | 64 | C | 1 | — |
| 29 | 1807 | Woburn | 64 | C | 1 | — |
| 30 | 1808 | Woburn | 64 | C | 1 | — |
| 31 | 1813 | Woburn | 64 | C | 1 | — |
| 32 | 1815 | Woburn | 64 | C | 1 | — |
| 33 | 1853 | Lowell | 64 | C | 1 | — |
| 34 | 1887 | Wilmington | 64 | C | 1 (1 health) | $646K |
| 35 | 2453 | Waltham | 64 | C | 2 | $666K |
| 36 | 2471 | Watertown | 64 | C | 1 | — |
| 37 | 2477 | Watertown | 64 | C | 1 | — |
| 38 | 1721 | Ashland | 63 | C | 1 | $586K |
| 39 | 1773 | Lincoln | 63 | C | 1 | $1170K |
| 40 | 1776 | Sudbury | 63 | C | 1 | $939K |
| 41 | 1778 | Wayland | 63 | C | 1 | $936K |
| 42 | 1803 | Burlington | 63 | C | 1 | $679K |
| 43 | 1824 | Chelmsford | 63 | C | 1 | $591K |
| 44 | 1852 | Lowell | 63 | C | 1 | $397K |
| 45 | 2141 | Cambridge | 63 | C | 0 | $893K |
| 46 | 2142 | Cambridge | 63 | C | 0 | $1727K |
| 47 | 2420 | Lexington | 63 | C | 1 | $1148K |
| 48 | 2421 | Lexington | 63 | C | 1 | $1148K |
| 49 | 2458 | Newton | 63 | C | 1 | $1117K |
| 50 | 2472 | Watertown | 63 | C | 1 | $738K |
| 51 | 2478 | Belmont | 63 | C | 1 | $1109K |
| 52 | 1748 | Hopkinton | 61 | C | 3 | $726K |
| 53 | 1826 | Dracut | 61 | C | 2 | $466K |
| 54 | 2149 | Everett | 61 | C | 1 | $605K |
| 55 | 1701 | Framingham | 60 | C | 0 | $613K |
| 56 | 1702 | Framingham | 60 | C | 0 | $564K |
| 57 | 1864 | North Reading | 60 | C | 0 | $680K |
| 58 | 1890 | Winchester | 60 | C | 0 | $1182K |
| 59 | 2476 | Arlington | 60 | C | 0 | $882K |
| 60 | 1469 | Townsend | 59 | C | 7 | $385K |
| 61 | 1730 | Bedford | 59 | C | 2 (1 health) | $878K |
| 62 | 1746 | Holliston | 59 | C | 7 | $621K |
| 63 | 2451 | Waltham | 59 | C | 2 | $709K |
| 64 | 2452 | Waltham | 59 | C | 2 | $780K |
| 65 | 1760 | Natick | 58 | C | 1 | $741K |
| 66 | 1801 | Woburn | 58 | C | 1 | $642K |
| 67 | 1851 | Lowell | 58 | C | 1 | $432K |
| 68 | 1854 | Lowell | 58 | C | 1 | $361K |
| 69 | 1863 | North Chelmsford | 58 | C | 1 | $478K |
| 70 | 1876 | Tewksbury | 58 | C | 5 (2 health) | $547K |
| 71 | 1880 | Wakefield | 58 | C | 1 | $670K |
| 72 | 2138 | Cambridge | 58 | C | 0 | $1089K |
| 73 | 2139 | Cambridge | 58 | C | 0 | $1066K |
| 74 | 2140 | Cambridge | 58 | C | 0 | $1070K |
| 75 | 1742 | Concord | 56 | C | 1 (1 health) | $1139K |
| 76 | 1749 | Hudson | 56 | C | 9 | $480K |
| 77 | 2238 | Cambridge | 56 | C | 0 | — |
| 78 | 2239 | Cambridge | 56 | C | 0 | — |
| 79 | 2474 | Arlington | 55 | C | 0 | $887K |
| 80 | 1474 | West Townsend | 53 | D | 0 | $428K |
| 81 | 2135 | Brighton | 53 | D | 0 | $684K |
| 82 | 1822 | Billerica | 51 | D | 3 (3 health) | — |
| 83 | 1866 | Pinehurst | 45 | D | 0 | — |
| 84 | 1879 | Tyngsboro | 45 | D | 0 | $533K |
| 85 | 2460 | Newtonville | 45 | D | 0 | $1124K |
| 86 | 1821 | Billerica | 43 | D | 3 (3 health) | $581K |
| 87 | 2176 | Melrose | 43 | D | 1 (1 health) | $796K |
| 88 | 1467 | Still River | 40 | D | 0 | — |
| 89 | 1472 | West Groton | 40 | D | 0 | — |
| 90 | 1525 | Linwood | 40 | D | 0 | — |
| 91 | 1718 | Village Of Nagog Woods | 40 | D | 0 | $359K |
| 92 | 1731 | Hanscom Afb | 40 | D | 0 | — |
| 93 | 1784 | Woodville | 40 | D | 0 | — |
| 94 | 1862 | North Billerica | 40 | D | 0 | $504K |
| 95 | 1865 | Nutting Lake | 40 | D | 0 | — |
| 96 | 2156 | West Medford | 40 | D | 0 | — |
| 97 | 2455 | North Waltham | 40 | D | 0 | — |
| 98 | 2456 | New Town | 40 | D | 0 | — |
| 99 | 2459 | Newton Center | 40 | D | 0 | $1336K |
| 100 | 2461 | Newton Highlands | 40 | D | 0 | $1155K |
| 101 | 2475 | Arlington Heights | 40 | D | 0 | — |
| 102 | 2479 | Waverley | 40 | D | 0 | — |
| 103 | 2495 | Nonantum | 40 | D | 0 | — |
| 104 | 2155 | Medford | 36 | F | 2 (2 health) | $716K |
| 105 | 2148 | Malden | 33 | F | 1 | $608K |
Recommended Buyer Guides for Middlesex County
Four sources — EPA, NSF, FEMA, CDC — drive the match.
- Best Water Filters for Lead — Lead above EPA action level in 1 ZIP code
- Best Lead Paint Test Kits — 71.7% 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 Middlesex County, Massachusetts
Overview
Middlesex County in Massachusetts covers 105 ZIP codes with an average Home Safety Score of C (58/100).
57 of 105 ZIP codes have recorded EPA violations. 15 health-based violations have been documented.
← Back to Massachusetts 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.