Hey... cool thread!

Re: wall of water... There are a few people that contend that there
are records of big rocks falling from the sky, hitting the sea. A
meteor (or bunch of meteors) could likely make for one heck of a wave,
that could travel a fair piece inland... Sorta sounds a bit like a wall
of water.

It's not a scientific book by any stretch, but Uriel's Machine
(Knight/Lomas) discusses this possibility a bit. The suggestion there
is that 7 meteors hit the earth (10,000 ish years ago), giving rise to
many of the flood myths. They even suggest that Great Salt Lake, and
the salt flats in Utah came about because the basin they are in
(mountainous region) was filled with sea water that after evaporation
yielded a salt lake and flats. I'm skeptical, but an interesting
thought none the less.

M