Bonnet Carré Crevasse

The Bonnet Carré Crevasse was an 1871 breech in the Mississippi River levees some 15 miles upriver of New Orleans, Louisiana which resulted in substantial flooding. It was the worst flooding much of New Orleans had experienced since Sauvé's Crevasse in 1849.

Bonnet Carré was an area in St. Charles Parish, Louisiana. The East Bank river levee collapsed here at high water so dramatically that attempts to quickly staunch the breech were soon abandoned in the face of the huge and powerful flow of water. The flood eventually spread through most of the East Bank of the Parish all the way to Lake Pontchartrain. The river water increased the water level in the lake and in the system connecting Pontchartrain to the Gulf of Mexico, its eventual outlet. Lake Pontchartrain overflowed its banks, with the water spreading into surrounding communities including the Lake and "Back of Town" sections of New Orleans.

The river levee was not restored at Bonnet Carré until 1883.

The area is now the site of the Bonnet Carré Spillway.