The rain lasted 40 days, after which the earth remained submerged for 150 additional days until the water began to subside. Sixty days after the water began to subside, Noah sent out a raven and then a dove in order to see if the water had receded completely.
Not Waiting for G‑d
וַיִּפְתַּח נֹחַ אֶת חַלּוֹן הַתֵּבָה אֲשֶׁר עָשָׂה: וַיְשַׁלַּח אֶת הָעֹרֵב וגו': (בראשית ח:ו–ז)
Noah opened the window he had made in the ark and sent out the raven. Genesis 8:6-7

As the Torah will recount, Noah did not leave the ark until G‑d told him to do so. So what was the purpose of seeing if the land was dry by sending out these birds?

The answer is that since G‑d had entrusted him with the survival of life, Noah felt responsible to take whatever natural steps would encourage G‑d to hasten the renewal of life on earth.

The pain of exile is compared to the raging waters of the Flood. Like the Flood, only G‑d can end the exile. But, like Noah, we can hasten the redemption by actively yearning for it and doing all in our power to hasten its arrival.1