the was certainly worldwide flooding about 15,000 years ago due to the end of the last ice age. i doubt it would have been a global flood but would certainly have been localised within various geographic areas, and would have affected every area of the globe at some stage or other.
with substantial amounts of water caught up in continental glaciers, global sea levels would have been approx 80m lower and civilisations would have flourished on what is now the continental shelf.
as the glaciers slowly melted, unimaginably massive glacial dams would have formed on the continents particularly in mountainous areas eg himalayas. eventually these dams would have had to break releasing seas of water towards the coast destroying everything along the way.
i believe this is the phenomena alluded to by the biblical great flood story and also explains why every culture has their own flood myth. the existence of the ice age, and the correspondingly lower sea levels are not disputed in scientific circles. it follows logically that the rising sea levels as the ice age melted would have resulted in widescale flooding. this phenomena could also explain the existence and destruction of atlantis - also described by plato in his dialogues.
noah would not have necessarily had to have been hearing messages from god in order to have the foresight to build an ark and start collecting animals to put on it. he would have just had to have had a degree of scientific and environmental knowledge about the impending devastation that would occur when the glacial dams inevitably collapsed.
we have no way of knowing the degree of civilisation that was achieved during this time as it was destroyed.. however archaeologists such as graham hancock have discovered and published findings of underwater monolithic constructions the likes of which could still not be constructed today with our modern technology. (underworld - graham hancock).
i think the old testament is true to the extent that it is one of the important records of human history and civilisation that was not lost during the dark ages or the burning of the library in alexandria.
the new testament i think is a bit of a crock it makes no sense to me at all.
