Arlington, MA: High Radon Risk — 58/100 (2026)
2 ZIP codes · 1 water system · Updated 2026-06-03
Water monitoring across Arlington 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 Arlington Compares
Data: EPA SDWIS Last verified: 2026-06-03
Arlington Water: The Quick Version
- Average lead level: 0.0028 mg/L.
- Homes built before 1986: 91% — older plumbing may contain lead solder.
- Estimated remediation: $2,400 per household.
- CDC health risk index: 9.88.
Water Systems Serving Arlington
Across most of Arlington, MA, residential water comes from a single utility. That provider sets rates, manages infrastructure maintenance, and files compliance reports with the EPA on behalf of the households it serves. Federal tracking data shows 1 system on record, but one carries the bulk of the service load.
Overview
We track water quality and home safety data for 2 ZIP codes in Arlington, Massachusetts, covering 1 community water system serving approximately 46,015 people.
No EPA violations recorded across any ZIP codes in Arlington — an excellent indicator of water quality.
Home Safety Score
Average Home Safety Score for Arlington: C (58/100)
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
Arlington water systems draw from: Surface water.
Lead & Copper
- Average lead level (90th percentile): 0.0028 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.
Areas with No Violations
| ZIP Code | Safety Score | System | Population |
|---|---|---|---|
| 02474 | C | Arlington Water Department (mwra) | 46,308 |
| 02476 | C | Arlington Water Department (mwra) | 46,308 |
All ZIP Codes in Arlington
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.
CDC Health Data for Arlington
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
How Old Is Arlington's Housing Stock?
With 91% 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
For residents trying to assess tap water risk in Arlington, the median build year of 1921 is the starting context. It signals that a majority of homes were constructed before 1986 — the year federal rules prohibited lead solder in new plumbing — and that a significant share likely predates 1970, when lead pipes were still a common choice for residential service connections. Neither risk tier is rare in this housing inventory.
Over half of homes in Arlington 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.
Arlington: Remediation Cost in Perspective
Placing remediation in the context of Arlington'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 Arlington 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 58% above the Massachusetts average.
Protecting Children from Lead in Arlington
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.
Before the federal solder ban, lead solder was a routine plumbing material, and 91% of the Arlington inventory was built in that earlier era — a share large enough to move household-level reads onto the standard list.
Sources: EPA Lead and Copper Rule, U.S. Census Bureau ACS, CDC childhood lead poisoning prevention guidelines.
Climate-Related Water Risk for Arlington
Flood exposure in Arlington is meaningful by NFIP measures — 395 claims on record and 100% of ZIP codes carrying FEMA flood zone designations. That level of activity makes flood history a relevant factor when evaluating local water quality over time.
Arlington has a moderate flood history with 395 FEMA claims averaging $7,881 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 Arlington
- 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 91% of homes built before 1986, lead solder is a real possibility.
Deep Dive Reports
Detailed analysis for Arlington, MA