What does Genesis 7:24 mean?

This verse brings us back to the Hebrew root word gabar, translated as "prevailed" in the ESV and other versions. It is a word used to refer to a military victory. The floodwaters "triumphed, overwhelmed, overcame or conquered" the surface of the land for 150 days, remaining victorious over everything beneath. Those who have witnessed a large river, a broken dam, or a tsunami have seen the immense power of moving water. Water only a few feet deep has the strength to tear down buildings and drown virtually any land animal. According to the Bible, the flood waters around the ark were never less than 18 cubits (22 feet or 7 meters) above the highest point of land. That's an invincible quantity of water, and nothing in its path survived (Genesis 7:23).

These 150 days include the first 40 days of torrential rain, followed at some point by the end of water gushing up from below. After this, the waters beginning to recede. But, for another 110 days, the flood waters utterly destroy everything in their path. As we'll see in the next chapter, the ark will finally come to rest on solid ground after those 150 days.