If the Flood happened as literalists say, then the Mesopotamians were much closer in history to the event, and their accounts conflict considerably with the Bible. For one thing, they say the ark was round, and not oblong. There's also the small problem that the two accounts disagree on which gods are real and therefore could have caused the Flood.
There's a Darren Aronofsky version of the story coming out soon, and like all of his work it will be excellent and I will be seeing it. I get that some atheists may think that's strange at first, but come on, it's just a fun story - why let the Christians have the rights to it? Let the secular world take it over! You'd see Beowulf and Clash of the Titans right? Plus, you'll get to see fundamentalists to go into conniptions over Aronofsky's version just like racists flipped out over Idris Elba playing Heimdall in Thor.
It's worth pointing out that in the Babylonian epic Gilgamesh, the ark-builder rather than futilely exhorting people to get to high ground, carefully avoids disclosing to his neighbors what exactly he's doing. "Um, nope, no, that's not a boat. Why, building a boat on high ground! That's crazy talk! Now step aside while I load these kangaroos which for some reason that looks oddly like it can be explained otherwise, will be completely forgotten in the Old Testament that people will write a few thousand years from now." (Note: one interesting idea is that the flooding of the Black Sea, which occurred in 5550 BC, may actually be the basis of the flood myth; it also may explain the diaspora of the Indo-European language family.)
In all seriousness, we love to beat up literal creationists because they're a fun and easy target, but the on-the-fence people who are inching closer to non-religion, and where our efforts are most likely to yield results, already don't believe this stuff, and probably don't care as much as we think about evolution.