Bedrocks have varying amounts of void spaces in them where groundwater accumulates. But Earth's bedrock consists of many types of rock, such as sandstone, granite, and limestone. If all bedrock consisted of a dense material like solid granite, then even gravity would have a hard time pulling water downward.

The rock below the Earth's surface is the bedrock. That means that water on the surface will try to seep into the ground below it. Nothing surprising here - gravity pulls water and everything else toward the center of the Earth. The saturated zone below the water table has water that fills the tiny spaces (pores) between rock particles and the cracks (fractures) of the rocks.Ī couple of important factors are responsible for the existence of groundwater: The dirt and rock in this unsaturated zone contain air and some water and support the vegetation on the Earth. The ground above the water table (the pink area) may be wet to a certain degree, but it does not stay saturated. Here is a simplified diagram showing how the ground is saturated below the water table (the solid blue area at the bottom). Water in the saturated groundwater system moves slowly and may eventually discharge into streams, lakes, and oceans. The part that continues downward through the soil until it reaches rock material that is saturated is groundwater recharge. Some part of the precipitation that lands on the ground surface infiltrates into the subsurface. Groundwater is a part of the natural water cycle (check out our interactive water cycle diagram). Water at very shallow depths might be just a few hours old at moderate depth, it may be 100 years old and at great depth or after having flowed long distances from places of entry, the water may have been in the ground for several thousand years. This water may occur close to the land surface, as in a marsh, or it may lie many hundreds of feet below the surface, as in some arid areas of the western United States. It is not always accessible, or fresh enough for use without treatment, and it's sometimes difficult to locate or to measure and describe. Some water underlies the Earth's surface almost everywhere, beneath hills, mountains, plains, and deserts. In fact, there is a over a thousand times more water in the ground than is in all the world's rivers and lakes.

They (and maybe you) may not realize that there is an immense amount of water in aquifers below the earth's surface. they pull down a lever and out of the ground below their feet comes clear, cool freshwater. These kids probably think there is some kind of magic happening here. Children using a pump to draw waterout of the ground.

Move water through sponge