On top of the saturated zone is the water table. The water table can be a few inches from the surface or be hundreds of feet below the ground. The water in lakes and rivers is called surface water. Sometimes surface water becomes groundwater. The water in the lakes and rivers soaks into the ground around and becomes groundwater.
Water can move through the ground like a slow moving river.
It is able to move through cracks in rocks, sand and gravel. An area that has lots of groundwater is called an aquifer. Wells can be drilled down into the aquifer and then the water can be used by people. Sometimes groundwater may be polluted. Many things can pollute the water.