The Arizal writes that of the 600,000 souls, the ones from the Dor Haflagah are always amongst us. They come back generation after generation. Now we know. The Torah is telling us where these souls of the Sodomites originated. G-d promised there never to be a flood of water.
Water is symbollic of Torah.
Today we have a flood of the evil inclination, a flood of scoffers. A generation from the time of Noach who tried to tear down his ark, his Taivah. And guess what, Taivah can be read two ways. The Torah wants us to know that in a time of flood it is only the Taivah that can save. Words of prayer.