I think it is God's way of telling low-tech people about massive geologic change, asking them to accept the details on faith.
The fact that science keeps discovering things which confirm what people of faith already know-- such as the existence of vast stores of water deep in the earth-- should not be a surprise.
"Remember, dear brothers and sisters, that few of you were wise in the world’s eyes or powerful or wealthy when God called you. Instead, God chose things the world considers foolish in order to shame those who think they are wise. And He chose things that are powerless to shame those who are powerful."
--Paul's first letter to the church at Corinth, 1:26-27
“No. Allegory for what?”
Water being a cleansing mechanism.
“The fact that science keeps discovering things which confirm what people of faith already know—”
People of faith do not know, they believe...thus faith. We were not there.
The final quote seems to be saying to remain humble, which is fine. I certainly might be missing the point though.