The flood in Genesis 7-8 was an historical event with many layers of meaning. It was a time when Yahweh judged the wicked justly – but it was more than that. Geerhardus Vos explains (note: “deluge” is another term for “flood”).
“The cosmic extent of the deluge-event is both negative and positive.
First, negatively, the flood destroyed the world (cf. Gen. 6). This is a catastrophic world-judgment. This fact is confirmed by pagan mythology, where it is associated with the chaos-flood out of which the world arose. The creation and the deluge both have cosmic significance. It was not confined to man; but the purpose was that God repented that he had created the world.
Second, positively, it is the commencement of a new world-order. The waters receded on the first day of the month and the first month of the year (cf. Gen. 8:13); therefore a new year. It also possibly attaches itself to the periodicity [time periods] of history and the berit [covenant] principle. Periodicity is generally shown by the covenants that appear at the beginnings of periods.
Now the deluge and the post-diluvian (post-flood) order of things prefigure eschatological crisis and the eschatological state. In other words, the deluge and ‘new creation’ are typical [that is, a type] of the absolute end of the world and the final renewal of the world.
For more info, see 2 Peter 3:1-7 after reading flood account in Genesis.
The above quote was taken from Geerhardus Vos’ The Eschatology of the Old Testament, page 81.