Why are graves above the ground in Louisiana?

Answer 1

I visited New Orleans on August 13, 2009 and did a tour of the city. Our tour guide told us that back in the day caskets used to be buried underground. However, since New Orleans is below sea level, the caskets would uproot from the ground and float down the streets during heavy rain / floods. They ending up in nearby parishes or many miles away, and with no labeling on the caskets it was difficult to find out where they belonged. As a result, the dead are now buried in above ground graves called mausoleums and appropriate labeling on the enclosure where the deceased is kept is required.

Answer 2

Because the ground in most coastal parts of Louisiana such as New Orleans is below sea level. When there is flooding and torrential rains it causes the bodies to unearth and float around when they aren't buried above ground.