Southborough, MA: High Radon Risk — 70/100 (2026)
1 ZIP code · 2 water systems · Updated 2026-06-03
Tap water in Southborough, MA scores well — low violation counts, above-average safety grade.
How Southborough Compares
Data: EPA SDWIS Last verified: 2026-06-03
Key Facts for Southborough Residents
- Average lead level: 0.001 mg/L.
- Homes built before 1986: 57% — older plumbing may contain lead solder.
- Estimated remediation: $2,400 per household.
- CDC health risk index: 12.17 — above typical levels.
Southborough's Water Providers
Across Southborough, MA, residential water comes from 2 primary utilities rather than a single consolidated provider. Each system operates independently — managing its own distribution infrastructure, rate schedules, and EPA compliance filings. Federal records track 2 water systems in the area, with these top providers accounting for the majority of residential connections.
Overview
We track water quality and home safety data for 1 ZIP code in Southborough, Massachusetts (population ~9,781), covering 2 community water systems serving approximately 82,876 people region-wide.
No EPA violations recorded across any ZIP codes in Southborough — an excellent indicator of water quality.
Home Safety Score
Average Home Safety Score for Southborough: B (70/100)
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
Southborough water systems draw from: Surface water.
Lead & Copper
- Average lead level (90th percentile): 0.0010 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)
The EPA recommends testing homes in Zone 1 and Zone 2 areas for radon.
Areas with No Violations
| ZIP Code | Safety Score | System | Population |
|---|---|---|---|
| 01772 | B | Southborough Dpw Water Division (mwra) | 10,514 |
All ZIP Codes in Southborough
- 01772 [B]
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.
Southborough 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
Southborough Infrastructure Age
With 57% 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
The character of Southborough's housing stock is one of deep historical layering — a median build year of 1988 signals a city built largely before the plumbing era changes of 1986 and 1970. Lead-soldered copper joints and, in the oldest properties, lead service lines are commonly present in this inventory. That context shapes what individual water testing may reveal, particularly in neighborhoods where the oldest housing is concentrated.
Over half of homes in Southborough 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 Southborough
Given current Southborough valuations, the remediation-to-property-value ratio is low — most homeowners are looking at a proportionally modest share that fits within routine financial planning.
Remediation costs in Southborough 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 45% above the Massachusetts average.
Southborough: 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.
Older interior plumbing shapes the local picture: 57% of Southborough homes predate the federal solder ban, and aggregate sampling either approaches or crosses the action benchmark. That mix makes a single-home draw a standard pre-purchase or pre-occupancy step.
Sources: EPA Lead and Copper Rule, U.S. Census Bureau ACS, CDC childhood lead poisoning prevention guidelines.
Southborough: Flood History & Water Damage Risk
5 FEMA flood insurance claims are on file for Southborough, and 100% of local ZIP codes fall within federally designated flood zones — enough to put flood exposure on the planning radar, though short of the concentrated-risk threshold where treatment-system vulnerability becomes a primary consideration.
Southborough has a moderate flood history with 5 FEMA claims averaging $1,132 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.
Deep Dive Reports
Detailed analysis for Southborough, MA