Paul, the permanent wiring is installed as high as possible for that reason. The County has allowed some exceptions to normal rules for installing most outlets above 8 feet and using heavy duty extension cords and plug strips. Quite a bit of rewiring was needed 2 years ago, the water was to the bottom of the second floor rafters. Not a problem so far this year though.
Ken, there's no drywall used on the first floor at all. Walls are concrete with epoxy paint, floors are stained concrete, the bar is even concrete. It cleans up quickly, just open the doors and start hosing the place out. The surfaces are cleaned and sanitized.
There's usually fair warning before water floods the building so there's time to move furniture and light weight stuff to the second floor. Coolers, freezers, stoves, ice makers, etc. are rolled into a trailer or out onto the floating docks. The extension cords and plug strips go out with the appliances and all that's left are bare walls and floors.
Dick, glad to hear she's floating and that you're not flooded (within just a couple of inches though). Here's the current levels on the Mississippi and Illinois Rivers;

The Illinois River is flooded south of you.
I look forward to seeing you and your cruiser at our June Festival, June 25-27, 2010. Come down early, we'll cruise the Pool.
Al