The lake is linked to the Gulf of Mexico through the Rigolets strait and Chef Menteur Pass through the Lake Borgne. The lake was formed some 2,600 to 4,000 years ago when the Mississippi River Delta’s alluvial deposits created its eastern and southern shorelines.

Its average depth is about 12 feet, but there are deeper shipping channels that are constantly dredged to ensure safe navigation.

Lake Pontchartrain is a 630-square mile estuary in southeastern Louisiana.