Lexington, MA: 2 Violations — 63/100 (2026)
2 ZIP codes · 3 water systems · Updated 2026-06-03
Water systems across Lexington produce average compliance results for MA overall — pockets with documented violations exist, and the variation between areas makes checking the specific system serving a given address the most useful step for residents here.
How Lexington Compares
Data: EPA SDWIS Last verified: 2026-06-03
What You Should Know About Lexington Water
- Your city's water systems recorded 2 violations in the past 5 years.
- Average lead level: 0.0018 mg/L.
- Homes built before 1986: 73% — older plumbing may contain lead solder.
- Estimated remediation: $2,400 per household.
- CDC health risk index: 9.88.
Who Supplies Your Water in Lexington
3 water utilities share the residential service territory in Lexington, MA — out of 3 total systems in federal records.
Overview
We track water quality and home safety data for 2 ZIP codes in Lexington, Massachusetts (population ~34,085), covering 3 community water systems serving approximately 72,543 people region-wide.
2 of 2 ZIP codes (100%) have recorded EPA violations. All violations are monitoring/reporting type.
Home Safety Score
Average Home Safety Score for Lexington: C (63/100)
The score combines three factors:
| Factor | What It Measures |
|---|---|
| Water Quality | EPA violations and compliance history |
| Lead Levels | 90th percentile lead concentration vs EPA action level |
| Radon Risk | EPA radon zone classification |
Water Sources
Lexington water systems draw from: Surface water.
Lead & Copper
- Average lead level (90th percentile): 0.0018 mg/L (EPA action level: 0.015 mg/L)
- 0 ZIP codes exceed the EPA lead action level
Radon Risk
Dominant radon zone: Zone 1 (High Risk)
- Zone 1 (High): 2 ZIP codes
- Zone 2 (Moderate): 0 ZIP codes
- Zone 3 (Low): 0 ZIP codes
The EPA recommends testing homes in Zone 1 and Zone 2 areas for radon.
Top Contaminants
| Contaminant | Category | Violations | ZIPs Affected |
|---|---|---|---|
| Stage 1 DBP Rule | Treatment Technique | 3 | 2 |
Areas with Most Violations
| ZIP Code | Safety Score | Violations | Health-Based | System |
|---|---|---|---|---|
| 02420 | C | 1 | 0 | Lexington Water Department (mwra) |
| 02421 | C | 1 | 0 | Lexington Water Department (mwra) |
All ZIP Codes in Lexington
Data Sources
- Water quality: EPA Safe Drinking Water Information System (SDWIS)
- Lead/copper: EPA Lead and Copper Rule sampling data
- Radon: EPA Map of Radon Zones
Updated daily.
Health Outcomes in Lexington
Source: CDC PLACES (County-level estimates). Water contamination can correlate with respiratory and chronic health conditions.
Compared to National Average
Vertical line = national average. ■ Above national · ■ Below national
Top Contaminants in Lexington Water
Based on EPA violation records. Check your ZIP code report for system-specific contaminant data.
Housing & Infrastructure in Lexington
With 73% of homes built before 1986, lead solder in plumbing is a potential concern. The EPA banned lead solder in 1986, but many older homes retain original plumbing.
Source: U.S. Census Bureau American Community Survey (ACS).
Housing Age Profile
Federal plumbing rules changed in two stages — lead pipes were phased out before 1970, and lead solder was banned in 1986 — but in Lexington, where the median build year is 1966, most of the housing was already in place before those rules took effect. The materials installed under older standards remain embedded in a substantial portion of the residential inventory today.
Over half of homes in Lexington were built before 1986, when lead solder was banned. Older plumbing may leach lead into drinking water, especially with corrosive water chemistry.
Source: U.S. Census Bureau ACS B25034.
Cost Context: What Remediation Means for Lexington Homeowners
Placing remediation in the context of Lexington's property market, the equity share is low — most homeowners here are weighing a financial commitment that fits comfortably within routine property planning, far from the threshold where remediation becomes a material equity decision rather than a standard upkeep consideration.
Remediation costs in Lexington are relatively low compared to home values. The $1,600–$3,300 estimated range is a small fraction of median property value. Home values are 104% above the Massachusetts average.
Lead Exposure Risk for Children in Lexington
Why children are most at risk: The CDC states there is no safe level of lead exposure for children. Children under 6 absorb lead more readily than adults, and even low levels can cause developmental delays, learning difficulties, and behavioral problems.
Although utility-side compliance with federal Lead and Copper requirements remains the system reference, that compliance does not extend down into interior plumbing. With 73% of Lexington stock built before the solder ban and aggregate readings at or beyond the action mark, a household-level sample becomes the practical way to close that information gap.
Sources: EPA Lead and Copper Rule, U.S. Census Bureau ACS, CDC childhood lead poisoning prevention guidelines.
Flood & Climate Risk in Lexington
Although Lexington's flood history doesn't reach high-severity thresholds, NFIP data documents 69 claims and FEMA maps place 100% of ZIP codes in designated flood zones — a combined profile that makes flood-related water quality considerations a reasonable planning baseline.
Lexington has a moderate flood history with 69 FEMA claims averaging $3,086 per payout. 100% of ZIP codes fall within FEMA flood zones. Flood events can contaminate drinking water and overwhelm treatment systems.
How flooding affects water quality: Flood events can introduce sewage, agricultural runoff, and industrial chemicals into water supplies. Even after floodwaters recede, contamination can persist in wells and aging infrastructure. Flood damage can add significantly to the estimated <strong>$2,400</strong> remediation cost per household.
Residents in flood-prone areas should consider flood insurance even outside FEMA zones — over 25% of flood claims come from low-to-moderate risk areas. After any flood event, test your water before drinking.
Source: FEMA National Flood Insurance Program (NFIP) claims data, FEMA flood zone designations.
What You Can Do in Lexington
- Test your water at home. City-level data shows averages — your tap may differ. NSF-certified test kits cost $20-40 and give results in days.
- Install a certified water filter. Filters rated for Stage 1 DBP Rule can reduce the most common contaminant found in Lexington's water.
- Check your home's plumbing. With 73% of homes built before 1986, lead solder is a real possibility.
Deep Dive Reports
Detailed analysis for Lexington, MA