How come bodies of water (lakes, rivers, wetlands, oceans even…) exist above ground instead of the water simply being absorbed by the earth?
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1) They *do* sink into the ground. Eventually it’ll hit an *impermeable* layer of dense bedrock that the water can’t go through. The ground will become saturated and no more water can drain down.
2) The ground slows the water down: imagine a cup with small holes in it. The water will drain out, but as long as water goes *in* faster than it drains, the water level will stay elevated.
3) Some kinds of soil are less permeable to water, like clay. Rock, obviously, doesn’t allow water to sink through very easily.
4) Water that drains through the soil will eventually either sink into an aquifer or get forced back up from pressure and form a spring.
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