
Aquifers & Flow
What Is an Aquifer? Groundwater in Plain English
An aquifer is a permeable layer of rock, sand, or gravel that stores and transmits enough groundwater to supply wells or springs.
Groundwater is hidden, but it is not mysterious once the layers and pathways are named. These guides translate hydrogeology into careful mental models without pretending that one diagram describes every site.

An aquifer is a permeable layer of rock, sand, or gravel that stores and transmits enough groundwater to supply wells or springs.