PFAS · Delaware
PFAS in Delaware drinking water: EPA’s final survey results
EPA’s national PFAS survey (UCMR 5) tested 35 of the community water systems that serve homes in Delaware. 17 found at least one of 29 PFAS above the laboratory reporting level, and 12 had a PFOA or PFOS sampling-location yearly average at or above EPA’s 4.0 ppt limit. Samples were collected from January 2023 to October 2025.
Data as of EPA UCMR 5 final release, August 2026 (file dated Aug 28, 2026) · EPA SDWIS 2026Q2 (file dated Jul 9, 2026). How we build these pages
PFPeA was the compound Delaware community systems found most often: 14 of 35 tested systems measured it above the reporting level. Across the country, 35% of surveyed community systems found at least one PFAS; in Delaware the share is 49%. The largest Delaware system with a detection, Artesian Water Company, serves 231,114 people and found 8 of the 29 compounds.
Which PFAS were found most often in Delaware
Each row counts the Delaware community water systems where that compound was measured above the reporting level at least once. A detection is a measurement, not a violation: most of these compounds have no federal limit.
| Compound | Systems where found | Systems tested | Share |
|---|---|---|---|
| PFPeA | 14 | 35 | 40% |
| PFHxA | 13 | 35 | 37% |
| PFOA | 12 | 35 | 34% |
| PFBS | 11 | 35 | 31% |
| PFOS | 9 | 35 | 26% |
| PFBA | 7 | 35 | 20% |
| PFHpA | 6 | 35 | 17% |
| PFHxS | 6 | 35 | 17% |
| PFNA | 2 | 35 | 6% |
| 6:2 FTS | 1 | 35 | 3% |
| 8:2 FTS | 1 | 35 | 3% |
| PFDA | 1 | 35 | 3% |
Delaware systems with the most PFAS found
The 10 surveyed community water systems that found the most different PFAS, with PFOA and PFOS compared to EPA’s 4.0 ppt limits on the yearly average at the highest sampling location. Larger systems come first when counts tie.
| Water system | People served | PFAS found (of 29) | PFOA | PFOS |
|---|---|---|---|---|
| Georgetown Water Department DE0000592 | 7,259 | 11 | 18.0 ppt at or above the MCL | 13.5 ppt at or above the MCL |
| Veolia Water Delaware, INC DE0000564 | 100,495 | 9 | 19.3 ppt at or above the MCL | — not detected above the reporting level |
| Artesian Water Company DE0000552 | 231,114 | 8 | 22.3 ppt at or above the MCL | 5.6 ppt at or above the MCL |
| Newark Water Department DE0000630 | 40,000 | 8 | 22.7 ppt at or above the MCL | 7.4 ppt at or above the MCL |
| Rehoboth Beach Water Department DE0000723 | 25,000 | 7 | 10.6 ppt at or above the MCL | 3.1 ppt below the MCL |
| Wilmington Water Department DE0000663 | 107,976 | 6 | 7.7 ppt at or above the MCL | — not detected above the reporting level |
| Dewey Beach Water Department DE0000825 | 31,000 | 5 | 9.5 ppt at or above the MCL | — not detected above the reporting level |
| Smyrna Water Department DE0000657 | 11,813 | 5 | 9.6 ppt at or above the MCL | 6.7 ppt at or above the MCL |
| Stage Village MHC DE0000569 | 93 | 5 | 6.9 ppt at or above the MCL | 8.0 ppt at or above the MCL |
| Rehoboth Pump District (Tui) DE0000991 | 81,417 | 4 | 2.2 ppt below the MCL | — not detected above the reporting level |
Counties with the most systems that found PFAS
- Sussex County 11 of 19 surveyed systems
- New Castle County 5 of 8 surveyed systems
- Kent County 1 of 8 surveyed systems