What does Genesis 7:19 mean?
As in the prior verse, Genesis uses the Hebrew root word gabar, translated as "prevailed or triumphed" to describe the victory of the floodwaters of God's judgment. This catastrophic effect is shown in how high the water rises over the surface of the ground. The water is said to cover all of the highest hā'rim. This term, hā'rim is also often translated as "hills," or even "high hills."This is important in the discussion of whether or not this was a planetary flood, or a "local" flood only affecting the regions inhabited by men. The tallest peaks in the Middle East region are not nearly as high as those in other places on earth. The highest point in the middle east is Mount Damāvand, in Iran, more than 18,000 feet (5,600 m) above sea level. Israel's highest point is in the Golan Heights, and rises almost 7,300 feet (2,200 m) above sea level. By comparison, Mount Everest is more than 29,000 feet (8,000 m) high, and some parts of Argentina are more than 22,000 feet (nearly 7,000 m) tall. In other words, according to proponents of a local flood, the amount of water needed to annihilate the early territory of men would have been far, far less than that needed to cover the peaks of the planet's highest mountains.
At the same time, others have speculated that the eruption of the waters from the deep, in combination with the enormous forces of the floodwaters on the earth, resulted in the creation of the mountains as we know them today. That would include these various points already mentioned.
In any case, the Bible is explicitly claiming that the waters from this flood covered every meaningful point of land, leaving no possibility of escape or rescue for those who were not on the ark.