RicS. Some time ago several of us had a go at the flood problem in this Origins forum. The site was called "Gilgamesh ripped off Genesis" or something like that. Most of us agreed the Old Testament flood story grew from one flood or a series of floods on the Sumerian plain. By definition the plain would have developed as a floodplain. The Gilgamesh and Noah stories certainly have many similarities. You might like to go back and comment on that thread.