Delaware, OH: High Radon Risk — 65/100 (2026)
1 ZIP code · 5 water systems · Updated 2026-06-03
Delaware shows moderate tap water quality for OH — some areas carry documented EPA violations while others meet standards without issues.
How Delaware Compares
Data: EPA SDWIS Last verified: 2026-06-03
What You Should Know About Delaware Water
- Average lead level: 0.0008 mg/L.
- Homes built before 1986: 43% — older plumbing may contain lead solder.
- Estimated remediation: $3,000 per household.
- CDC health risk index: 11.03.
Who Supplies Your Water in Delaware
Residential addresses in Delaware, OH are served by 3 primary water providers out of 5 systems in federal records. Each system maintains separate infrastructure and files its own EPA compliance reports, so service conditions are not uniform across the city.
Overview
We track water quality and home safety data for 1 ZIP code in Delaware, Ohio (population ~59,027), covering 5 community water systems serving approximately 1,526,610 people region-wide.
No EPA violations recorded across any ZIP codes in Delaware — an excellent indicator of water quality.
Home Safety Score
Average Home Safety Score for Delaware: C (65/100)
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
Delaware water systems draw from: Surface water.
Lead & Copper
- Average lead level (90th percentile): 0.0008 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 |
|---|---|---|---|
| 43015 | C | Del-Company Water Company, Inc. | 150,000 |
All ZIP Codes in Delaware
- 43015 [C]
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.
Health Outcomes in Delaware
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
Housing & Infrastructure in Delaware
With 43% 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
Over the decades, Delaware accumulated housing from multiple construction periods. The median build year of 1997 places the midpoint of that stock near the 1986 threshold when lead solder in plumbing became federally prohibited — leaving a sizable share of homes on each side of that safety line.
Most homes in Delaware were built after 1986, reducing the risk of lead contamination from plumbing. Older homes should still be tested.
Source: U.S. Census Bureau ACS B25034.
Cost Context: What Remediation Means for Delaware Homeowners
Placing remediation in the context of Delaware'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 Delaware 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 70% above the Ohio average.
Lead Exposure Risk for Children in Delaware
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 43% of the Delaware 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.
Flood & Climate Risk in Delaware
Multiple flood events have been recorded for Delaware through the NFIP — 42 claims in total, with 100% of ZIP codes in FEMA-designated zones — pointing to a flood exposure profile that merits inclusion in a water quality assessment without reaching high-severity planning territory.
Delaware has a moderate flood history with 42 FEMA claims averaging $12,533 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 Delaware
- 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 43% of homes built before 1986, lead solder is a real possibility.
Deep Dive Reports
Detailed analysis for Delaware, OH