Water table

A water table (from the Greek "phrear" meaning a well) is a mass of water contained in fissures in the subsoil; it is generally accessible through a well or by drilling. The bottom of a water table can be an impermeable layer as can the top; in this case it becomes confined. Near the sea, the fresh water table meets the salt water table; the fresh water being denser, passes under the salt water table.