Hamden, CT: High Radon Risk — 40/100 (2026)
3 ZIP codes · 3 water systems · Updated 2026-06-03
Within Hamden, water quality data indicates below-average safety by CT standards — independent testing is a reasonable precaution for residents whose systems show active violations.
How Hamden Compares
Data: EPA SDWIS Last verified: 2026-06-03
What You Should Know About Hamden Water
- Homes built before 1986: 76% — older plumbing may contain lead solder.
- Estimated remediation: $3,000 per household.
Who Supplies Your Water in Hamden
In Hamden, CT, residential water supply is distributed across multiple utilities rather than concentrated in one. The 3 leading providers out of 3 tracked systems each control their own infrastructure, file separate EPA compliance reports, and set independent rate schedules.
Overview
We track water quality and home safety data for 3 ZIP codes in Hamden, Connecticut (population ~60,116), covering 3 community water systems serving approximately 456,251 people region-wide.
No EPA violations recorded across any ZIP codes in Hamden — an excellent indicator of water quality.
Home Safety Score
Average Home Safety Score for Hamden: D (40/100)
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
Hamden water systems draw from: Groundwater, Surface water.
Lead & Copper
- Lead data: not yet available for Hamden
- 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 |
|---|---|---|---|
| 06514 | D | Regional Water Authority | 418,900 |
| 06517 | D | Regional Water Authority | 418,900 |
| 06518 | F | Regional Water Authority | 418,900 |
All ZIP Codes in Hamden
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 Hamden
With 76% 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
Reading the housing age data for Hamden — median build year 1965 — the overriding implication is that the plumbing materials inside a typical home here reflect pre-1986 construction standards. In practical terms, that means lead-soldered copper joints are common across much of the housing stock. Where those materials are present, water can leach lead as it moves through joints — a pathway that corrosion control treatment under federal rules is designed to reduce, though it cannot eliminate lead risk where the plumbing materials themselves contain lead.
Over half of homes in Hamden 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 Hamden Homeowners
When remediation costs are measured against Hamden home values, the resulting ratio is in the low tier — addressing documented water and safety issues here claims only a minor fraction of typical equity, and most homeowners are in a position where the financial commitment is straightforward rather than a material burden on their household budget.
Remediation costs in Hamden are relatively low compared to home values. The $2,000–$4,100 estimated range is a small fraction of median property value. Home values are 25% below the Connecticut average.
Lead Exposure Risk for Children in Hamden
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.
Practically, the structural drivers in Hamden — 76% pre-rule stock and citywide monitoring at or beyond the regulatory benchmark — make an in-home draw the practical way to translate aggregate averages into the specific conditions at one address.
Sources: EPA Lead and Copper Rule, U.S. Census Bureau ACS, CDC childhood lead poisoning prevention guidelines.
Flood & Climate Risk in Hamden
Because Hamden's NFIP claim count reaches 501 and 100% of ZIP codes fall within FEMA-designated flood zones, flood exposure here operates differently than it does in lower-claim communities. In areas with isolated flood events, water-quality infrastructure can typically absorb the stress and recover between events. In communities with repeated high-volume flooding, treatment plants face recurring overload conditions, private wells in FEMA-designated zones accumulate repeated infiltration episodes, and distribution systems experience repeated pressure events that can drive backflow. The claim record for this area points to that second category: a flood environment where water infrastructure stress is periodic and documented, not theoretical.
Hamden has a significant flood history with 501 FEMA flood insurance claims on record, averaging $4,084 per claim. With 100% of ZIP codes in FEMA-designated flood zones, flood risk is a major concern for homeowners and water quality.
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 Hamden
- 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 76% 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 Hamden, CT