Again:
Gen. 7:
18 The waters became overwhelming and kept increasing greatly upon the earth, but the ark floated on the surface of the waters.
19 The waters overwhelmed the earth so greatly that all the tall mountains under the whole heavens were covered. 20 The waters rose up to 15 cubits above the mountains.
21 So all living creatures that were moving on the earth perished—the flying creatures, the domestic animals, the wild animals, the swarming creatures, and all mankind.
22 Everything on dry land that had the breath of life in its nostrils died. 23 So He wiped
every living thing from the surface of the earth, including man, animals, creeping animals, and the flying creatures of the sky. They were all wiped off the earth;
only Noah and those with him in the ark survived.
...8:1 But God gave attention to Noah and to all the wild animals and domestic animals that were with him in the ark, and God caused a wind to blow over the earth, and the waters began to subside.
When it says:
all the tall mountains under the whole heavens were covered and after that "
fifteen cubits above the mountains"
... it obviously means that among
ALL THE HIGH HILLS/MOUNTAINS is included
THE HIGHEST ONE of all of them, so
the 15 cubits were from the highest mountain upward ... not 9 meters from the river level or any other hill besides the tallest one
.
The account is talking about the
WHOLE EARTH, UNDER THE WHOLE HEAVEN being covered.
The Deluge that the Scriptures refer is global:
1 Pet. 3:20 (...) God was patiently waiting in Noah’s day, while the ark was being constructed, in which
a few people, that is, eight souls, were carried safely through the water.
Matt. 24:
37 For just as the days of Noah were, so the presence of the Son of man will be.
38 For as they were in those days before the Flood, eating and drinking, men marrying and women being given in marriage, until the day that
Noah entered into the ark, 39 and they took no note until
the Flood came and swept them all away, so the presence of the Son of man will be.
If the Deluge had not been global, all the years of building the ark (an immense ship) would have been avoided only if Noah and his family, without even worrying about any animal to survive, had made a trip to a distant land that did not would be affected by that supposed local flood. Obviously, the Bible story is about a planetary Deluge.
There are proofs of a global deluge all around the planet. Atheists and others confound these proofs with other events they say occurred also in the past.
1) Marine fossils in high lands,
2)
heavy transformations of the terrain all around the planet,
3) animals found frozen whose digestive condition shows they were surprised by a sudden catastrophe
4) agglomerations of hundreds of skeletons of non-native animals in remote caves,
5) stories of the flood in hundreds of ancient communities,
6) the fact that the diversity of civilizations and human language converge in the same area that coincides with the settlement of Noah and his family post- Deluge,
7) dozens of cities sunk in the depths of the sea
8) the fact that the time of the formation of modern civilizations coincides with the time that the Bible assigns to the event of the Flood, etc.