Wilmington
Wilmington, DE water profile — supply sources, drought status, wastewater reuse, and the key water issues facing the city.
wilmington water department
surface water (rivers/reservoirs) · local government · PWSID DE0000663
Below EPA's 15 ppb lead action level at last testing.
Source: EPA Safe Drinking Water Information System (SDWIS) · 2026 Q1
With about 71,948 residents, Wilmington ranks as the largest city in Delaware and a small but growing city. Water in Wilmington is sourced chiefly from Delaware River and coastal aquifers, the backbone of Delaware's supply.
The defining water pressure here mirrors the state's: saltwater intrusion. Low-lying coastal aquifers are vulnerable to saltwater intrusion and contamination.
Statewide, Delaware recycles about 5% of its wastewater with minimal reuse programs. Locally, Wilmington faces severe to extreme drought conditions.
The Delaware state profile covers the regional supply outlook; the issues below detail what's driving Wilmington's water future.
New Castle County water quality
Source: EPA SDWIS · 2026 Q1
At a glance
- Population ~71,948 (largest in Delaware)
- Primary sources: Delaware River and coastal aquifers
- Drought: severe to extreme conditions
- State reuse rate: ~5% of wastewater
Statewide drought history
% of Delaware in severe+ drought (Extreme (D3) now).
Source: U.S. Drought Monitor
Common questions
Is tap water safe in Wilmington?
Wilmington's largest water system, WILMINGTON WATER DEPARTMENT, serves about 107,976 people. EPA records show 1 health-based violation(s) since 2016 and a most-recent 90th-percentile lead level of 0 ppb (EPA action level is 15 ppb). Always check your own provider's annual Consumer Confidence Report.
Where does Wilmington get its water?
WILMINGTON WATER DEPARTMENT draws primarily from surface water (rivers/reservoirs), part of Delaware's supply from Delaware River, coastal aquifers.
Related water issues
Saltwater Intrusion
As coastal aquifers are over-pumped and seas rise, saltwater pushes inland and contaminates freshwater supplies for cities from Florida to California.
ExplorePFAS Contamination
Per- and polyfluoroalkyl substances persist in water supplies for decades. New federal limits are forcing utilities nationwide to invest in advanced treatment.
Explore