There's isn't symbolism in the creation account. Those were real people and real events. Adam and Eve in the Garden were real people with real events. Noah and the Flood were actual events. Jesus affirmed the story of Noah.
(Matthew 24:37-39 NIV) As it was in the days of Noah, so it will be at the coming of the Son of Man. {38} For in the days before the flood, people were eating and drinking, marrying and giving in marriage, up to the day Noah entered the ark; {39} and they knew nothing about what would happen until the flood came and took them all away. That is how it will be at the coming of the Son of Man.