There are many flood myths from all over the earth.
They have their origins in the end of the last ice age 14000 - 8000 years ago.
The sea level worldwide was more than a 100 m lower than today, which gave the people immense living place that no longer exists.
As this huge ice melt, in many places of the earth were catastrophic floods, making the sealevel to rise.
The mesopotamic flood myths (Gilgamesh, Noah and some others) could all be rooted to one of such LOCAL floods.
Scientists Pitman and Ryan found out, that about 8000 years ago, the Black Sea was a freshwater lake. As the Mediterranian sea rose, it broke through the Bosporus and flooded the area 1 year long, creating the black sea, a huge catastrophy for the people living there.
If you look at the hebrew words in the flood account, earth could mean land and mountains could mean hills. So it is not in contradiction to a 'local' flood.
The Watchtower sometimes quotes Flavius Josephus work 'Jewish antiquities' to prove their point.
In 'Jewish Antiquities' Josephus mentions that there were many others who survived the flood.
I have the book in german... so i can't quote it...
In Paragraph 94-95 Josephus mentions other ancient sources who talk of a mountain called Baris where many fled during the flood and survived, one coming in an arc.
In P. 109 Josephus talks about Noahs sons who went down the mountain and convinced many others who were on that mountain to come down with them.
There are so many geological, scientific, historical proof, that there couldn't have been a flood 4400 years ago. Dig a little bit in the web.
Dendrochronology (study of tree rings) has some proof, the study of Ice Cores, Cave Paintings who are 20-40000 years old would have been destroyed in such a flood.
Find out more about Cosquer Cave in France.
At the time that was the tiping point for me... as the only entrance to this cave with magnificent paintings is 40m under sea level... so the human painters must have lived during the ice age when sea level was down, being one of thousands of proofs of human existence more than 6000 years ago.
Cosquer cave also shows that the sea level was not higher than today, as those cave paintings would show signs of salt water if they would have been flooded.