This might be a hard question to know the answer to, but are there any notable cultures in the world that do NOT have a flood myth? What stories does that culture have instead?
It seems to me that the ancestors of pretty much every known civilization on earth must have experienced some kind of catastrophic flooding.
But maybe there is a culture whose ancestors only have stories of volcanoes destroying civilization, or meteors or sickness or famine. Or maybe cultures who have no catastrophic stories?
In case someone here cannot answer it, you might want to try /r/AskAnthropology since it is question of cultural anthropology.
The Norse mythology contains no reference to a great flood - except that when Ragnarök (doomsday) happens, there will be a great flood. But there's no reference to such an event in the past.