Not embarrassing at all. You assume the earth had the same characteristics before the flood as after. This is clearly could not be the case if one takes the Genesis account at face value, as Jesus Himself did.
The issue is that the Earth would not have the characteristics it has now, had the flood actually occurred. It would take a geologically long time for the Earth to recover from such a cataclysm, assuming of course that the excess water could be destroyed somehow.
But if there were some magic means of destroying the excess water without destroying the Earth beneath it, one wonders why God did not simply bring it to bear against the evil men and babies, who were themselves two-thirds water, rather than the more ham-handed technique he used.