Derby, CT: High Radon Risk — 45/100 (2026)
1 ZIP code · 2 water systems · Updated 2026-06-03
Derby, CT water systems: poor compliance record, lower-tier safety grade.
How Derby Compares
Data: EPA SDWIS Last verified: 2026-06-03
What You Should Know About Derby Water
- Homes built before 1986: 82% — older plumbing may contain lead solder.
- Estimated remediation: $3,000 per household.
Who Supplies Your Water in Derby
Derby, CT is covered by 2 major water utilities out of 2 federally tracked systems, each managing its own pipes, treatment processes, and EPA filings. What a household gets from the tap depends on which provider's system serves that address.
Overview
We track water quality and home safety data for 1 ZIP code in Derby, Connecticut (population ~12,150), covering 2 community water systems serving approximately 770,656 people region-wide.
No EPA violations recorded across any ZIP codes in Derby — an excellent indicator of water quality.
Home Safety Score
Average Home Safety Score for Derby: D (45/100)
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
Derby water systems draw from: Surface water.
Lead & Copper
- Lead data: not yet available for Derby
- 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 |
|---|---|---|---|
| 06418 | D | Regional Water Authority | 418,900 |
All ZIP Codes in Derby
- 06418 [D]
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.
Housing & Infrastructure in Derby
With 82% 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
When more than half a city's housing predates the 1986 federal ban on lead solder, plumbing-era lead risk becomes a citywide concern rather than an exception. Derby's median build year of 1967 places it squarely in that category.
Over half of homes in Derby 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 Derby Homeowners
Property equity in Derby sits at a moderate ratio to estimated remediation costs — a classification that reframes the household financial perspective from routine maintenance to deliberate budgeting, where most homeowners have a realistic path to addressing documented water and safety issues if they map the financial commitment against available resources before committing to scope.
Remediation costs are moderate relative to home values in Derby. The estimated $2,000–$4,100 range is manageable for most homeowners but still worth budgeting for. Home values are 40% below the Connecticut average.
Lead Exposure Risk for Children in Derby
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 stock in Derby represents 82% of the inventory, and citywide monitoring runs at or above the federal action level — making an in-home read a standard household-level step.
Sources: EPA Lead and Copper Rule, U.S. Census Bureau ACS, CDC childhood lead poisoning prevention guidelines.
Flood & Climate Risk in Derby
Flood risk in Derby occupies the middle ground: 41 NFIP claims and 100% of local ZIP codes within FEMA flood zones. At that level, the risk pathways connecting flooding to water quality — treatment system stress, well infiltration, distribution backflow — become relevant considerations during significant flood events, even if day-to-day water quality is unaffected by flood history.
Derby has a moderate flood history with 41 FEMA claims averaging $3,012 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>$3,000</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 Derby
- 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 82% of homes built before 1986, lead solder is a real possibility.
- Review your water system's CCR. Your utility publishes an annual Consumer Confidence Report with detailed test results. Request it or find it online.
Deep Dive Reports
Detailed analysis for Derby, CT