As predicted by the prophet Costner

Okay, so what happens is the sun shines on the oceans and evaporates water and makes clouds. And then it rains everywhere, including on land, which is largely water soluble. So some of the land melts and runs off into rivers. And the rivers flow downhill until the water ends up back in the ocean. And when it gets evaporated again, it leaves all those bits of the surface world behind. Doesn’t it seem like the water cycle would eventually dissolve all the dry land and wash it down into the sea? Is this something I should be concerned about?