Louisiana
St. Mary Parish drinking water quality
16 active public water systems serve 63,113 people in St. Mary Parish. 5 are compliant, 11 had at least one EPA violation in the past three years, 3 are designated serious violators, and 1 carries a health flag.
Needs attention
Community water systems
12 systems, largest first| System | Serves | Status | Rules violated, 3 yr | Unresolved |
|---|---|---|---|---|
|
City of Morgan City Water System |
12,703 | 1 | 0 | |
|
Water & Sewer Commission 4 of ST Mary |
9,709 | 1 | 0 | |
|
City of Patterson Water System |
8,456 | 2 | 0 | |
|
City of Franklin Water Supply |
8,325 | 5 | 2 | |
|
ST Mary Water & Sewer Comm #3 |
7,828 | 1 | 0 | |
|
ST Mary Parish W&s #2 Bayou Vista |
5,379 | 0 | 0 | |
|
City of Berwick |
5,024 | 2 | 1 | |
|
ST Mary Parish Water Sewerage Comm 1 |
2,823 | 4 | 2 | |
|
ST Mary Par JT Water Sewer Commission 5 |
1,240 | 2 | 0 | |
|
Port of West ST Mary |
400 | 2 | 1 | |
|
Glencoe Community Water System |
190 | 1 | 0 | |
|
Berwick Bayou Vista WW Commission |
0 | 1 | 0 |
Non-community systems (4: schools, campgrounds, workplaces, restaurants)
These systems serve places people visit rather than homes.
| System | Serves | Status | Rules violated, 3 yr | Unresolved |
|---|---|---|---|---|
|
Cypremort Point State Park |
500 | 0 | 0 | |
|
Quintana Marina |
280 | 0 | 0 | |
|
Compass Minerals la |
156 | 0 | 0 | |
|
Bayview Development |
100 | 0 | 0 |
Inactive systems (31, no longer operating or reporting)
Kept for the record and excluded from the county totals above. Browse inactive systems.
About this data
Totals cover active systems. Systems serving more than one county are counted in each county. EPA counts the rules a system was in violation of, not the individual violations; one rule can carry several.
Source: the U.S. EPA's Enforcement and Compliance History Online system (ECHO), which publishes the federal Safe Drinking Water Information System. EPA's terms and values are shown as published. The Louisiana records are from EPA's data refresh of Oct 7, 2026; EPA refreshes this data quarterly, and states report to EPA with a lag of three to six months, so the newest violations may not appear yet. Retrieved from ECHO on Oct 11, 2026.