If I understand it correctly, a being created humankind; it became angry with what it had created; it then decided to drown the evidence of its flawed creation.
The problem with that story is that it makes the being look like a clay-master who blames the clay for the flaws in the finished product; a being who had yet to learn the truth of the fact that the fruit doesn't fall far from the tree. A tree is known by its fruit. If we be of god, and we be sinful, what kind of a tree does that make god?
Who wrote the account? When was it written? What was, and still is, a core Middle Eastern belief about God?
The belief held about God is that God is the power behind everything that happens. Some Muslims hold the belief that they cannot even move their little finger each time lest it first be the will of God. Another deeply held religious belief in Biblical times is that God is all good and merciful. How to reconcile these beliefs about God. It is still human nature today, is to examine one's behavior towards the person(s) who has passed on.
The account was written, my man, after the fact--and we can see they felt their behavior had been so bad when held up to the goodness of God it deserved eradication. Take note of Noah's behavior. The most righteous man living at that time said nothing to anyone about their bad behavior; did not warn them of retribution, and afterwards suffered so much from survivor's guilt he became a drunk. One son tried to cover up this dirty linen, the other decided to air it publicly.
Further, they decided in order to prevent the previous evil from surfacing again, everyone should spread out so as not be so readily influenced, However, humans being what we are, people instead began gathering and building the great city of Babylon. So many came in, it became known as the city of many languages, so many languages they no longer understood each other. We are told this is why the great city collapsed. (Remember, people spoke the way they did instead of all the same because it was the will of God, as was everything.)
Moving along through Genesis, is the theme that societies that lacked discipline were doomed to fail. The most obvious sign of an undisciplined society? Loose sexual morals and lack of hospitality.
Note, these are all things our ancient ancestors, barely out of the Stone Age, warned their children and descendants about. Parents, today, still try to do the same: Warn their children of the mistakes they made, hoping the children will learn from them. Doesn't work that well today either, does it?
Children's version: Be good or a flood will wash you away. Don't tell the neighbors your dad drinks. Build a tower, create new languages.