[mikekchar]

Not an expert in the matter, but I'm guessing the pressure on such a wall would be too great. One of the things that caused the death of many people in the big tsunami after the Tokoku earthquake was the assumption that if you just went up to the roof of your apartment building you would be safe. Unfortunately, the wave just wiped out everything. Huge concrete buildings were just flattened.

To be honest, I have often wondered how the powerplant survived at all. I guess it was high enough up and that only the generators got clobbered, but I haven't looked into it in detail.