PFAS · Louisiana
PFAS in Louisiana drinking water: EPA’s final survey results
EPA’s national PFAS survey (UCMR 5) tested 263 of the community water systems that serve homes in Louisiana. 48 found at least one of 29 PFAS above the laboratory reporting level, and 1 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 May 2026.
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
PFBA was the compound Louisiana community systems found most often: 37 of 263 tested systems measured it above the reporting level. Across the country, 35% of surveyed community systems found at least one PFAS; in Louisiana the share is 18%. The largest Louisiana system with a detection, New Orleans Carrollton Water Works, serves 334,903 people and found 6 of the 29 compounds.
Which PFAS were found most often in Louisiana
Each row counts the Louisiana 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 |
|---|---|---|---|
| PFBA | 37 | 263 | 14% |
| PFPeA | 12 | 263 | 5% |
| PFOS | 7 | 263 | 3% |
| PFHxA | 6 | 263 | 2% |
| PFBS | 5 | 263 | 2% |
| PFOA | 5 | 263 | 2% |
| PFHpA | 3 | 263 | 1% |
| 6:2 FTS | 2 | 263 | 1% |
| PFHxS | 2 | 263 | 1% |
| HFPO-DA (GenX) | 1 | 263 | 0% |
| PFNA | 1 | 263 | 0% |
Louisiana 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 |
|---|---|---|---|---|
| Town of Vidalia Water System LA1029011 | 6,354 | 8 | 19.0 ppt at or above the MCL | 7.9 ppt at or above the MCL |
| New Orleans Carrollton Water Works LA1071009 | 334,903 | 6 | 1.0 ppt below the MCL | 1.1 ppt below the MCL |
| City of Plaquemine Water System LA1047005 | 14,043 | 5 | 3.1 ppt below the MCL | 3.0 ppt below the MCL |
| Village of Parks Water System LA1099008 | 12,801 | 4 | 3.2 ppt below the MCL | 2.2 ppt below the MCL |
| New Orleans Algiers Water Works LA1071001 | 52,785 | 3 | 1.0 ppt below the MCL | 1.1 ppt below the MCL |
| Parish Utilities of Ascension LA1005035 | 9,732 | 3 | — not detected above the reporting level | 1.1 ppt below the MCL |
| St Mary Parish W&s #2 Bayou Vista LA1101015 | 5,379 | 3 | — not detected above the reporting level | — not detected above the reporting level |
| Schriever Water Treatment Service Area LA1109002 | 116,460 | 2 | — not detected above the reporting level | — not detected above the reporting level |
| Assumption Parish Ww District 1 LA1007001 | 21,366 | 2 | — not detected above the reporting level | — not detected above the reporting level |
| Houma Water Treatment Service Area LA1109001 | 11,658 | 2 | — not detected above the reporting level | — not detected above the reporting level |
Counties with the most systems that found PFAS
- St. Mary Parish 6 of 7 surveyed systems
- Jefferson Parish 3 of 4 surveyed systems
- Caddo Parish 3 of 6 surveyed systems
- St. James Parish 3 of 4 surveyed systems
- Orleans Parish 2 of 2 surveyed systems
- Ouachita Parish 2 of 12 surveyed systems
- Bossier Parish 2 of 6 surveyed systems
- Terrebonne Parish 2 of 2 surveyed systems