Water Basics 101

Apr 9, 2014

This map portrays the volume of water being depleted from rivers, lakes and aquifers on a daily basis (MGD = million gallons per day).
Credit EPRI, 2014

Math helps us understand the causes of water shortages, how much water we’re wasting, as well as predict flooding.  The big picture can be seen when you grasp how much water is falling as rain or snow, moving into rivers or aquifers, and how much is being used in cities, industry and farms.  An explanation of the current water situation from the National Geographic can be found here.   

A recent article from the National Geographic said Ogallala Aquifer has one of the highest rates of groundwater consumption in the entire country.

What is an aquifer?  It’s an underground layer of water-bearing rock.  The rock is permeable, which means liquids and gases can pass though according to a recent article from National Geographic.

There are two types of aquifers: confined and unconfined.

An unconfined aquifer is covered by permeable rock and can receive water from the surface.  The water table rises and falls depending on the amount of water entering and leaving.  It is only partially filled with water.

A confined aquifer is trapped between two layers of rock and is filled with water.  More information about what an aquifer is can be found in this article from the National Geographic.