Key Concepts

Sources of Water

Tesalia artesian spring, Machachi, Ecuador

An artesian aquifer is under pressure. The aquifer is usually surrounded by impermeable rock and the aquifer is typically made of sandstone or other porous rocks or sediment. The pressure built up in an aquifer will push water to the surface and create a permanent fountain when an artesian aquifer is tapped. The pressure in the aquifer will force the water up the well or crack without the use of a mechanical aid. This sometimes leads to spectacular water fountains. Artesian water matches spring water's range of characteristics, and brands often promote artesian quality as a distinguishing factor.

When the water's pressure brings it to the surface, that positive pressure in the aquifer can prevent contaminants from the ground or on the surface from seeping into the pressurized aquifer, making an artesian aquifer well protected.