Somerville, MA: High Radon Risk — 68/100 (2026)
3 ZIP codes · 2 water systems · Updated 2026-06-03
Water monitoring across Somerville paints a mid-range picture within MA — solid compliance in some service zones, documented concerns in others. Most violations on record are concentrated in specific areas, and the overall grade has held in the middle tier without major shifts in recent monitoring cycles.
How Somerville Compares
Data: EPA SDWIS Last verified: 2026-06-03
Key Facts for Somerville Residents
- Average lead level: 0.0039 mg/L.
- Homes built before 1986: 86% — older plumbing may contain lead solder.
- Estimated remediation: $2,600 per household.
- CDC health risk index: 9.88.
Somerville's Water Providers
Somerville, MA draws its residential water from 2 separate providers among the 2 federally tracked systems. Each operates independently, with its own infrastructure, rate structure, and compliance record.
Overview
We track water quality and home safety data for 3 ZIP codes in Somerville, Massachusetts (population ~78,099), covering 2 community water systems serving approximately 142,745 people region-wide.
No EPA violations recorded across any ZIP codes in Somerville — an excellent indicator of water quality.
Home Safety Score
Average Home Safety Score for Somerville: C (68/100)
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
Somerville water systems draw from: Surface water.
Lead & Copper
- Average lead level (90th percentile): 0.0039 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): 3 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.
Areas with No Violations
| ZIP Code | Safety Score | System | Population |
|---|---|---|---|
| 02143 | B | Somerville Water Department (mwra) | 81,045 |
| 02144 | B | Somerville Water Department (mwra) | 81,045 |
| 02145 | C | Somerville Water Department (mwra) | 81,045 |
All ZIP Codes in Somerville
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.
Somerville Community Health Snapshot
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
Somerville Infrastructure Age
With 86% 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
Somerville's housing stock is predominantly older, with a median build year of 1901 that reflects decades of construction before federal plumbing standards were tightened. The 1986 ban on lead solder and the pre-1970 era of lead service lines are both relevant benchmarks here — a significant share of the residential inventory predates one or both of those cutoffs, creating an elevated baseline for plumbing-related lead risk that aggregate water quality data may not fully reflect at the household level.
Over half of homes in Somerville 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.
How Remediation Costs Compare in Somerville
Placing remediation in the context of Somerville'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 Somerville are relatively low compared to home values. The $1,733–$3,533 estimated range is a small fraction of median property value. Home values are 65% above the Massachusetts average.
Somerville: Lead Risk & Vulnerable Populations
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.
86% of Somerville housing dates to the pre-rule era, alongside aggregate readings hovering at the federal action mark — household-level confirmation through a draw-test kit fits the local picture.
Sources: EPA Lead and Copper Rule, U.S. Census Bureau ACS, CDC childhood lead poisoning prevention guidelines.
Somerville: Flood History & Water Damage Risk
NFIP records stretching across multiple decades show Somerville accumulating 33 claims and carrying 100% of its ZIP codes inside FEMA flood zones — evidence of meaningful exposure that extends beyond isolated incidents. The mechanisms linking flooding to water quality haven't changed: treatment facilities can be overwhelmed, wells can be infiltrated, and distribution systems can experience backflow. For a community at this exposure level, those mechanisms shift from hypothetical to periodically relevant.
Somerville has a moderate flood history with 33 FEMA claims averaging $17,418 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>$2,600</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 Somerville
- 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. An NSF-certified pitcher or under-sink filter removes most common contaminants.
- Check your home's plumbing. With 86% of homes built before 1986, lead solder is a real possibility.
Deep Dive Reports
Detailed analysis for Somerville, MA