Skip Discover Education Main Navigation
Skip Discover Education Main Navigation

Home> Aquifer


An aquifer is a layer of rock with water moving through it
Key Context
Aquifers contain many porous spaces that allow water to flow from one space to another. The water in an aquifer flows much more slowly than water on the surface of the ground. The speed at which the water flows depends on the size of the rock in the aquifer, as well as the rock’s ability to absorb the water. Water that is held in an aquifer, called groundwater, is a major freshwater resource. The depth at which groundwater is found depends on how low the bottom layer of the aquifer is. Humans generally use wells or other irrigation devices to bring groundwater from aquifers to the surface. One of the world’s largest aquifers is the Ogallala aquifer, which runs underneath the Great Plains in the United States. It is said to contain enough groundwater to cover the entire United States to a depth of one and a half feet.