The flood is parable, not literal.
>"And he said unto them, Unto you it is given to know the mystery of the kingdom of God: but unto them that are without, all these things are done in parables:That seeing they may see, and not perceive; and hearing they may hear, and not understand; lest at any time they should be converted, and their sins should be forgiven them." - Mark 4:11-12
Jesus taught in parables and asked if you don't understand this parable how will you understand any of the parables because scripture is full of parables.
Remember, Jesus came for the LOST sheep of Israel.
The FIRMAMENT separates the "waters above" from the "waters below". Revelation 17:15 tells you the waters, where the PROSTITUTE sits, stands for people, multitudes, nations, and languages.
The waters are people.
In Egyptian mythology, Atum created Himself out of the primordial waters, the waters of Chaos, the waters of inactivity.
In the Old Testament, God created the heavens and the earth (not the planet and a place you go when you die, think "waters" above and below) and He hovered over the waters and created Adam.
If the waters are people, multitudes, nations and languages, what does that mean about the flood? Jesus told us not to fit into this world. God in the OT promised never to flood the earth again, and set a rainbow in the sky.
Do you think it's a coincidence the people who worry about population and push LGBTQ use the rainbow as a symbol?