LXX Gen 7:11

ἐν τῷ ἑξακοσιοστῷ ἔτει ἐν τῇ ζωῇ τοῦ Νῶε τοῦ μηνός, ἑβδόμῃ καὶ εἰκάδι τοῦ μηνός, τῇ ἡμέρᾳ ταύτῃ ἐρράγησαν πᾶσαι αἱ πηγαὶ τῆς ἀβύσσου, καὶ οἱ καταράκται τοῦ οὐρανοῦ

In the six hundredth year of Noah’s life, on the seventeenth day of the second month, all the fountains of the great deep burst forth, and the floodgates of the heavens were opened.