What is an Aquifer
Let's Talk Aquifers
An aquifer is a geologic formation beneath our feet formed by permeable material, such as sand or gravel, capable of storing and giving water. Water occupies the void spaces between sand grains, gravel, or rock fractures.
Aquifers in the Mississippi embayment are sediment-rich geologic formation comprised of sand and gravels.
There are many aquifers in the Mississippi embayment, but we will highlight the big FOUR.
- Mississippi River Valley Alluvial (MRVA) aquifer– was deposited by the Mississippi River and composed mostly of sand and gravel; offers huge amounts of water; and mostly used by agriculture in Arkansas, Mississippi, and Louisiana. This aquifer is not confined so is recharged directly by rain and rivers.
- Shallow aquifer – a simple name given to unconfined aquifer conditions covering much of west Tennessee that represents the upper most aquifer and is composed of sand and gravel. Used some for agriculture in rural areas of this region, it is of greater importance and concern in Shelby County as it is contaminated in places and leaks into the deeper Memphis aquifer.
- Memphis aquifer – also called the Sparta aquifer in Arkansas and Mississippi, is very extensive covering nearly the same extent of the Mississippi embayment, composed mostly of sand, thicker and confined closer to the Mississippi River; and thinner and unconfined as you move toward the edges of the embayment. This is a very important aquifer to Memphis and the surrounding communities for municipal and industrial uses.
- Fort Pillow aquifer – even deeper and below the Memphis/Sparta aquifer, it is thinner than its upper counterpart; composed of sand; and used by several water systems like West Memphis, the Millington Naval Base, and partially by the City of Millington and Memphis Light, Gas and Water (MLGW).