Question for you. About 97% of all the water on the planet is salt water. If it rained enough to flood the entire surface of the planet to a depth of tens of thousands of feet then all that salt water mixed with the fresh water and polluted it. So what did Noah drink once all the water receded?
who’s to say that all that water was as salty as it is now, or that there wasn’t rain enough to fill fresh water run-off lakes? I am not a scientist, so I will say I don’t know, but although your question is thought provoking: it doesn’t disparage the theory of creation.
I do appreciate that you are thinking though, and this discussion is helpful, I hope!
Wine