County · Louisiana
St. Mary Parish, Louisiana: drinking water records
This overview covers 8 ZIP codes and 12 community water systems in St. Mary Parish. It also stands in for 0 ZIP codes whose utility has too little EPA data for a page of its own.
System population figures are summed from EPA registry records and can overlap where wholesalers and retail systems serve the same people. They are not a Census county-population estimate.
Water systems with the most complete records
| Water system | People served | PFAS survey results | PFAS found | Health-based violations | Lead, 9 in 10 homes at or below |
|---|---|---|---|---|---|
| City of Morgan City Water System LA1101005 | 12,703 | 120 | 0 | 3 | 0 ppb |
| Water & Sewer Commission 4 of St Mary LA1101011 | 9,709 | 120 | 1 | 5 | 0 ppb |
| City of Patterson Water System LA1101006 | 8,456 | 120 | 2 | 6 | 0 ppb |
| City of Franklin Water Supply LA1101003 | 8,325 | 120 | 1 | 46 | 2 ppb |
| St Mary Water & Sewer Comm #3 LA1101010 | 7,828 | 120 | 1 | 3 | 3.3 ppb |
| City of Berwick LA1101014 | 5,024 | 120 | 1 | 1 | 0.7 ppb |
| St Mary Parish W&s #2 Bayou Vista LA1101015 | 5,379 | 120 | 3 | 0 | 0.3 ppb |
| St Mary Parish Water Sewerage Comm 1 LA1101009 | 2,823 | 0 | 0 | 3 | 0.8 ppb |
| St Mary Par Jt Water Sewer Commission 5 LA1101012 | 1,240 | 0 | 0 | 1 | 3.1 ppb |
| Port of West St Mary LA1101013 | 400 | 0 | 0 | 9 | 0 ppb |
| Glencoe Community Water System LA1101004 | 190 | 0 | 0 | 2 | 4 ppb |
| Berwick Bayou Vista Ww Commission LA1101002 | 0 | 0 | 0 | 3 | 1 ppb |
ZIP reports in St. Mary Parish
No ZIP report in this county is published yet.
Sources and scope
EPA UCMR 5 occurrence data, samples collected 2023-01-03 – 2026-06-17, final release, August 2026 (file dated Aug 28, 2026); EPA SDWIS via ECHO, 2026Q2 extract (file dated Jul 9, 2026); EPA service-area boundaries v3.0; Census 2020 ZCTAs. Page generated 2026-09-03.
Counts cover the systems that report this county to EPA. A water system may cross county lines. "Found" means at least one result at or above the laboratory reporting level; it is not a compliance finding.