Lake Borgne is a lagoon of the Gulf of Mexico in southeastern Louisiana. Although early maps show it as a lake surrounded by land, coastal erosion has made it an arm of the Gulf of Mexico. Its name comes from the French word borgne, which means "one-eyed."

Lake Pontchartrain is an estuary located in southeastern Louisiana in the United States. It covers an area of 630 square miles (1,600 km2) with an average depth of 12 to 14 feet. Some shipping channels are kept deeper through dredging. It is roughly oval in shape, about 40 miles (64 km) from west to east and 24 miles (39 km) from south to north.