Click on this image to see a detailed map of NOLA elevation from LIDAR imagery.  Anything that is indicated with Blue to light blue is below sea level.  The highest ground is in red.  You can clearly see the levees in red - especially on the Mississippi River.  The French quarter is the oldest part of the city and is therefore on relatively high ground.  the rest of the city - especially to the north was swamp when the French Quarter was established. 
NOLA ELEVATION MAPS
Click on this image to see a the same detailed imagery with major streets and highways overlaid.  The interstate highways are serving as helicopter pads and boat launches right now.
Click on this image to see the FEMA flood zones (in tan) overlaid on the city.  Not surprisingly, most of the city lies in a FEMA hazardous flood zone. 
Click on this image to see the locations of a couple music venues near and dear to my heart in the NOLA region.  Most seem high enough that they should have not gotten any flood damage (except maybe the Saenger - gack!).  Wind damage is anyone's guess.  Alas..
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