Beth...yes...basic structural geology (=non-controversial) would say 2 things:
1: Increased column of water in faults (increased fluid pressure) would weaken any fault. But, this fluid pressure from New Orleans would be unlikely to be tranmitted to the depths where larger quakes could nucleate...at least not quickly.

The weight of the water would increase vertical stressed..and this would occur right away. This would weaken "normal fault"....those related to crustal extension...or in this case...gravity. Normal faults is what you would have here...but the most active ones would be offshore to the south...and they may be shallow-enough that they would not do large quakes.

Opinion...not something to worry about right now in New Orleans...
Chris