High Quality Content by WIKIPEDIA articles! Lake Borgne is a lagoon in eastern Louisiana of the Gulf of Mexico. Due to coastal erosion, it is no longer actually a lake but rather an arm of the Gulf of Mexico. Its name comes from the French word borgne, which means "one-eyed". The three large lakes, Maurepas, Pontchartrain, and Borgne cover 55% of the Pontchartrain Basin. Lakes Maurepas and Pontchartrain are separated by land bridges of cypress swamp and fresh/intermediate marsh. A brackish marsh land bridge and Lake St. Catherine separate Lake Pontchartrain from Lake Borgne. The Rigolets and Chef Menteur Pass are the two open water connections between Pontchartrain and Borgne.