Unexplained bubbling in Louisiana’s Bayou Corne and Grand Bayou was reported in June and July 2012 to state and local officials. On Aug. 3 of that year, a large area of wooded swamp in the Bayou Corne area began to subside, resulting in the formation of a sinkhole that is now about 25 acres in size. That same month, state officials issued a declaration of emergency and ordered the mandatory evacuation of about 150 nearby households. The order is still in effect.
After investigation by the Louisiana Department of Natural Resources and other government agencies, it was determined that a sidewall collapse of an underlying cavern had occurred in the Napoleonville Salt Dome. Salt domes are large, ancient formations in the ground created as a consequence of the relative buoyancy of salt when buried beneath other types of sediment. Caverns are formed by pumping water underground to dissolve the salt and create a void.
