Lead Risk in Delaware: Housing, Water, LCRI Data
Avg lead: 0.0023 mg/L · 1 ZIPs over EPA limit · 0% pre-1986 housing · Updated 2026-05-31
Data: EPA Lead and Copper Rule, CDC, U.S. Census Bureau Last verified: 2026-05-31
City Water Quality Map: Delaware
Each circle represents a city. Size indicates population, color indicates water quality grade. Tap a circle for details.
Cities with Highest Lead Levels in Delaware
| # | City | Lead (mg/L) | Over Limit | Pre-1986 | Population | |
|---|---|---|---|---|---|---|
| 1 | Lewes | 0.0230 | 1 | 26% | 17,286 | Details → |
| 2 | Winterthur | 0.0120 | 0 | 0% | 687 | Details → |
| 3 | Milton | 0.0072 | 0 | 26% | 4,340 | Details → |
| 4 | Hockessin | 0.0070 | 0 | 52% | 60 | Details → |
| 5 | Montchanin | 0.0070 | 0 | 100% | 60 | Details → |
| 6 | Felton | 0.0066 | 0 | 36% | 2,382 | Details → |
| 7 | Lincoln | 0.0061 | 0 | 31% | 1,077 | Details → |
| 8 | Dagsboro | 0.0060 | 0 | 36% | 2,059 | Details → |
| 9 | Harrington | 0.0052 | 0 | 43% | 3,839 | Details → |
| 10 | Dover Afb | 0.0035 | 0 | 0% | 11,000 | Details → |
Lead Risk Overview
The average 90th percentile lead level across Delaware water systems is 0.0023 mg/L — within EPA limits. Out of 83 ZIP codes with lead data, 1 exceed the EPA action level.
Housing Age and Lead Risk
Lead plumbing solder was banned in 1986. In Delaware, approximately 0% of housing was built before this date, creating elevated risk of lead in residential plumbing.
Lead can enter water through:
- Lead service lines connecting water mains to homes
- Lead solder joints in copper plumbing
- Brass fixtures and faucets containing up to 8% lead (pre-2014)
Children's Blood Lead Levels
CDC surveillance data for children tested in Delaware:
| Year | Children Tested | BLL >= 5 ug/dL | BLL >= 10 ug/dL |
|---|---|---|---|
| 2018 | 12,947 | 0.9% | 0.3% |
| 2019 | 13,205 | 1.2% | 0.4% |
| 2020 | 7,881 | 1.3% | 0.3% |
| 2021 | 9,074 | 1.5% | 0.3% |
| 2022 | 12,824 | 0.9% | 0.2% |
The CDC states there is no safe level of lead exposure, particularly for children under 6. Even low levels can cause developmental delays, learning difficulties, and behavioral problems.
LCRI Funding and Service Line Replacement
The EPA's Lead and Copper Rule Improvements (LCRI) require water systems to inventory all service lines and replace lead lines within 10 years.
Federal funding for Delaware:
| Metric | Value |
|---|---|
| FY2025 allotment | $28.6M |
| Additional subsidy | 49% (grants/forgiveness) |
| National total | $3.0B |
Cities with Highest Lead Levels
| Rank | City | Lead Level (mg/L) | ZIPs Over Limit | Pre-1986 Housing | Population |
|---|---|---|---|---|---|
| 1 | Lewes | 0.0230 EXCEEDS | 1 | 26% | 17,286 |
| 2 | Winterthur | 0.0120 | 0 | 0% | 687 |
| 3 | Milton | 0.0072 | 0 | 26% | 4,340 |
| 4 | Hockessin | 0.0070 | 0 | 52% | 60 |
| 5 | Montchanin | 0.0070 | 0 | 100% | 60 |
| 6 | Felton | 0.0066 | 0 | 36% | 2,382 |
| 7 | Lincoln | 0.0061 | 0 | 31% | 1,077 |
| 8 | Dagsboro | 0.0060 | 0 | 36% | 2,059 |
| 9 | Harrington | 0.0052 | 0 | 43% | 3,839 |
| 10 | Dover Afb | 0.0035 | 0 | 0% | 11,000 |
Health Effects of Lead Exposure
Lead exposure affects every organ system. Key health risks include:
Children: Developmental delays, reduced IQ, behavioral problems, slowed growth
Adults: Kidney damage, high blood pressure, reproductive issues, nerve disorders
Pregnant women: Lead crosses the placenta and affects fetal development
How to Test for Lead
- Contact your water utility — many offer free lead testing
- Use a certified test kit ($20-$50) from a hardware store
- Hire a certified lab ($150-$400) for comprehensive testing
- Run cold water for 2+ minutes before drinking, especially in the morning
- Install a NSF/ANSI 53-certified filter rated for lead removal
Data Sources
- Lead levels: EPA Lead and Copper Rule
- Blood lead: CDC National Lead Surveillance
- LCRI funding: EPA DWSRF allotments
- Housing age: U.S. Census Bureau American Community Survey
Updated daily.
Concerned about lead in your water?
Lead levels vary by water system and housing age. Enter your ZIP code to see lead data specific to your area and find out if your water exceeds EPA limits.
Test Your Water for Lead →Frequently Asked Questions
Does Delaware have lead in its drinking water?
The average 90th percentile lead level across Delaware is 0.0023 mg/L (EPA action level: 0.015 mg/L). 1 ZIP codes exceed the EPA limit. Lead can enter water through older pipes and service lines even when source water is clean.
How old are homes in Delaware?
Approximately 0% of housing in Delaware was built before 1986, when lead solder was banned in plumbing. Older homes have higher risk of lead contamination from pipes, solder joints, and fixtures.
How many children in Delaware have elevated blood lead levels?
According to CDC data (2022), 0.9% of tested children in Delaware had blood lead levels at or above 5 ug/dL. The CDC states there is no safe level of lead exposure for children.
How much federal funding does Delaware receive for lead pipe replacement?
Delaware receives $28.6M in federal LCRI funding (FY2025) for lead service line inventory and replacement. 49% is available as grants or loan forgiveness.
How can I test my water for lead in Delaware?
Local water utilities in Delaware offer free or low-cost lead testing. Certified home test kits ($20-$50) and certified labs ($150-$400) are also available. Free testing is common, especially for homes built before 1986.