You have resolved certain beliefs concerning the Bible over time, why not try to resolve this Noah's Flood story as well. I think you accept it as a Biblical truth, well, even Biblical truths must leave evidence, must leave a footprint, must have environmental consequences.
You can't determine the truth of this story by reading the Bible because you firstly must determine if it is a symbolic story or a literal story. Have a read about what we know from the studies of planet earth some 4.5 thousand years back. There are many branches of science that you can glean information from. There have been studies made of the hypothetical Ark.
Why don't you clear this up for yourself one and for all.
The water you mentioned is not liquid water, it is a type of water trapped inside the molecular structure of minerals and is probably what enables this planet to carry so much water at the surface. There are no forces possible that can drive this water back to a liquid state and deliver it to the surface, if there was and it happened the planet would crush itself.
If you then discover that this is a symbolic story read it again and see what it then means to you.
