ZIP Code 02420 Water Quality & Testing Report
Lexington, MA · Middlesex County County · Updated for 2026
Is Tap Water Safe to Drink in ZIP 02420 (Lexington, MA)?
Caution / Filtration Recommended: Tap water in ZIP code 02420 (Lexington, MA) has compliance concerns, earning an EPA Safety Grade of C (63/100) due to 0 health violation(s) and 1.8 ppb lead. While treated by Lexington Water Department (mwra), residents are advised to use an NSF/ANSI 53 certified water filter for drinking and cooking.
Water Safety Grade
Fair — Some compliance concerns
Health Violations
0
Total Violations
1
Lead Risk
High
Contaminants
0
Active Water Quality Issues Detected
EPA records show 1 unresolved violation. Contact Lexington Water Department (mwra) for current status.
About Tap Water in ZIP Code 02420
Tap water in ZIP code 02420 (Lexington, MA) is distributed by Lexington Water Department (mwra) (EPA ID: MA3155000), serving approximately 34,074 residents. Based on EPA Safe Drinking Water Act compliance records, this system receives a water safety grade of C with a composite quality score of 63/100.
Water System
Lexington Water Department (mwra)
EPA ID: MA3155000
Water Source
Surface Water
Population Served
34,074 residents
County
Middlesex County County, Massachusetts
Lead Levels in ZIP 02420
EPA action level: 15 ppb | Public health goal: 0 ppb
Lead Level: 1.8 ppb — Very Low
Lead exposure risk in 02420 is rated High. EPA models estimate a 53% exposure probability based on housing and infrastructure age.
EPA model estimate based on housing age and infrastructure
Water Hardness & Mineral Content
Grains per gallon (GPG) & Parts per million (PPM / mg/L)
Water in ZIP 02420 is classified as Soft (53 mg/L / 3.1 GPG). Soft water produces abundant soap lather, prevents scale buildup in water heaters, and does not leave spots on dishes.
Grains per gallon
Parts per million CaCO3
Official EPA SDWIS Database Entry
Utility: Lexington Water Department (mwra) · PWSID: MA3155000
Violation History
Past 5 years — EPA SDWIS data
Lexington Water Department (mwra) has recorded 1 violation, but none are health-based (e.g., administrative or monitoring infractions). 1 violation remains unresolved in EPA tracking records.
Regulatory compliance risk for this utility is rated Moderate based on past reporting and enforcement records.
Contaminants Detected
Contaminants with health-based violations on record
No health-based contaminant violations are on record for ZIP code 02420 under the Safe Drinking Water Act.
⚖ Enforcement Actions
Water Source & Environmental Factors
Surface Water
This system draws water from lakes, rivers, or reservoirs. Surface water is treated to remove sediment, microorganisms, and chemical contaminants before reaching taps.
Highest potential
Estimated annual flood-related costs per property
% of household income spent on energy — indicator of older infrastructure
EPA Radon Zone 1 — highest potential for radon in indoor air. Homeowners should test their home for radon and consider mitigation if levels exceed 4 pCi/L.
Water Quality Testing in ZIP 02420
Tap Water & Well Testing Recommendations
Residents in ZIP code 02420 served by Lexington Water Department (mwra) can test tap water or private well systems to verify water purity. Testing detects hidden contaminants before they impact family health.
Tap Water Testing Steps
- 1.Conduct a certified lead check if your home was constructed before 1986.
- 2.Use certified lab testing kits rather than uncalibrated test strips for regulated compliance.
- 3.Sample water from both your kitchen faucet and water heater to compare line purity.
Private Well Testing Steps
- •Test for Coliform bacteria and Nitrates annually.
- •Test for heavy metals, radon, and PFAS every 3 years.
- •Send samples to a state-certified drinking water laboratory recognized by Massachusetts Department of Environmental Protection.
🛡 What Should You Do? — ZIP 02420 Recommendations
Some compliance concerns — take precautions
- ⚠ Use a certified NSF/ANSI 53 filter for drinking and cooking water if you have young children
- ⚠ Never give unfiltered tap water to infants in formula — use certified bottled or filtered water
- ⚠ Request a copy of the Consumer Confidence Report to see what was detected and when
- ⚠ Call the EPA Safe Drinking Water Hotline: 1-800-426-4791
Recommended Water Treatment Systems:
NSF 53 Lead Pitcher Filter
Specifically certified to reduce lead and copper at the tap.
NSF 58 Under-Sink RO System
Advanced filtration for PFAS, fluoride, nitrates, and organic chemicals.
Frequently Asked Questions — ZIP 02420 Water Quality
Is tap water safe to drink in ZIP code 02420?+
How do I get my water tested in ZIP 02420 (Lexington, MA)?+
How hard is the tap water in 02420?+
Should I test private well water in 02420?+
What is the lead level in 02420 tap water?+
Is there an active boil water notice in 02420?+
Who provides tap water to 02420?+
What water filter should I use in 02420?+
Data Sources & Methodology
Water quality data for ZIP code 02420 is compiled from the EPA Safe Drinking Water Information System (SDWIS), EPA ECHO enforcement database, UCMR5 unregulated contaminant monitoring, and Consumer Confidence Reports filed by Lexington Water Department (mwra). Safety scores are composite metrics derived from violation history, lead levels, enforcement actions, and infrastructure risk indicators. Data reflects a 5-year monitoring window. Last dataset update: 2024. View EPA source data →