Delaware
Water quality data from the EPA Safe Drinking Water Information System
Water Systems
1,387
Active public water systems
Population Served
1.10M
Residents with piped water
Lead Violations
32
Systems exceeding 15 ppb
Copper Violations
81
Lead & Copper Rule
Average Lead Level
EPA Action Level: 15 ppb
MCLG (health goal): 0 ppb
Average across 489 systems with reported lead data.
Violations Detected
113 water systems in Delaware have reported violations under the Lead and Copper Rule. These utilities are required to notify customers and take corrective action.
Water Systems: Highest Lead Levels
| System Name | City | Population | Lead Level | Status | Sample Date |
|---|---|---|---|---|---|
| DOVER | 15,000 | 10.00 ppb | OK | 2004-12-31 | |
| BETHANY BEACH | 12,450 | 6.90 ppb | OK | 2025-12-31 | |
| BETHANY BEACH | 12,000 | 4.90 ppb | OK | 2025-12-31 | |
| NEWARK | 18,015 | 4.00 ppb | OK | 2022-06-30 | |
| DOVER | 11,000 | 3.50 ppb | OK | 2023-12-31 | |
| DOVER | 51,000 | 2.30 ppb | OK | 2023-12-31 | |
| WILMINGTON | 100,495 | 2.00 ppb | OK | 2023-12-31 | |
| DOVER | 39,491 | 2.00 ppb | OK | 2026-12-31 | |
| LONG NECK | 11,000 | 1.10 ppb | OK | 2023-12-31 | |
| NEWARK | 231,114 | 1.00 ppb | OK | 2026-12-31 | |
| NEWARK | 40,000 | 1.00 ppb | OK | 2024-12-31 | |
| DOVER | 13,114 | 1.00 ppb | OK | 2019-12-31 | |
| DOVER | 81,417 | 0.71 ppb | OK | 2024-12-31 | |
| DOVER | 13,467 | 0.62 ppb | OK | 2026-12-31 | |
| WILMINGTON | 107,976 | 0.00 ppb | OK | 2023-12-31 |
Showing top 15 of 464 systems with lead data. Action level: 15 ppb.
Systems With Active Violations
These water systems have exceeded EPA limits and must take corrective action.
DOVER · Pop. 81,417
Lead: 0.71 ppb (2024-12-31)
NEWARK · Pop. 40,000
Lead: 1.00 ppb (2024-12-31)
NEWARK · Pop. 18,015
Lead: 4.00 ppb (2022-06-30)
DOVER · Pop. 17,208
Lead: 0.00 ppb (2024-12-31)
DOVER · Pop. 13,467
Lead: 0.62 ppb (2026-12-31)
BETHANY BEACH · Pop. 12,450
Lead: 6.90 ppb (2025-12-31)
DOVER · Pop. 13,114
Lead: 1.00 ppb (2019-12-31)
Water Source Types
Air Quality
GoodAvg AQI
44.5
PM2.5
6.1 µg/m³
Unhealthy Days
5
Primary Pollutant
Ozone
Source: EPA AirNow & American Lung Association 2024 State of the Air. AQI scale: 0–50 Good · 51–100 Moderate · 101–150 Sensitive Groups · 151+ Unhealthy.
PFAS Contamination
Moderate DetectionPFAS (per- and polyfluoroalkyl substances), known as “forever chemicals,” are a group of synthetic chemicals that persist indefinitely in the environment and human body. The EPA set a maximum contaminant level (MCL) of 4 parts per trillion (ppt) for PFOA and PFOS in April 2024. View national PFAS tracker →
Systems Tested
62
PFAS Detected
24
Detection Rate
38.7%
Exceeding MCL (4 ppt)
5(8.1%)
Highest recorded level: 18 ppt (EPA MCL: 4 ppt). DuPont chemical legacy in region influences contamination