Disclaimer: I have often considered creating a CreationistRingo alter ego to debate the other side. (I have been called argumentative and I can't deny it wthout shooting myself in the foot.) Unfortunately, I've come to the conclusion that it can't be done. There is no "other side". Creationism is the closest thing to a pure vacuum that humans have attained. Having said that, here goes:
Well i guess it is my turn then, to begin i will also start with an overused but valid question, where did the water all go?
Back where it came from.
Where would enough water to cover the earth even come from?
God had it up His sleeve.
The Flood was obviously a miracle, like the talking snake, walking on water, etc. It makes no more sense to look for scientific evidence of a Flood than it does to look for fossil snakes with vocal cords.
Maybe christians just stole from the greek flood story!
The Greeks knew the real truth about the flood but they embellished their myths with a lot of naked chicks for marketing reasons.
by applying the same power over water that was later displayed by Moses at the Red Sea, except instead of making a passage across the sea it made the water sweep over the land until it covered everything;
Since the Bible says the flood waters were fifteen cubits deep (Genesis 7:20), we should be able to calculate how much water is necessary to make a layer fifteen cubits deep covering the whole surface of the earth, up the sides of the mountains and so on.