What is an Artesian Spring?

water well

An Artesian well, or Artesian spring, is a source of ground water that is forced to the earth’s surface by of pressure caused by underground layers of rock surrounding the aquifer. It differs from a regular water well in that it doesn't require a pump to get the water to the surface. The only requirement is gravity and the pressure it creates. For this reason, Artesian springs occur at the base of a mountain or hill where the water can flow down into a well.

Why Does it Matter?

Bottled water brands like to use language specific to the manner in which the water comes to the earth’s surface. While the source of ground water may be the same, technically, water is only truly ‘artesian spring water’ if it flows naturally to the surface by pressure from non-permeable rock strata. Water trapped in the way is considered to be under artesian pressure. But gravity is also another important factor in determining what water qualifies as artesian, and how it is forced out through rocks to the earth’s surface. Typically, a mountain or hill gathers rain water which filters down into the aquifer beneath the first later of rock, and then flows underground until it can find a fissure in the rock to force its way out. The top end of the aquifer is called the ‘water table’, which unconfined water and needs to be pumped out to be accessed. Artesian water comes from trapped or confined water.

artesian well The word artesian comes from the town of Artois in France, the site of the old Roman city of Artesium, where the world’s most famous free flowing wells were drilled centuries ago during the Middle Ages.

Water brands like to promote the fact that their water is ‘artesian’, and that the natural processes that allow the water to be accessed give it a special taste or health benefit. The truth is, most artesian bottled water is the same, with the exception of the alkalinity or PH in the water. Water with naturally occurring high PH levels generally taste better because they are less acidic and have more minerals, which humans generally like to taste when they drink a nice cold glass of water. Bottled artesian water with a PH over 7.7 is considered to be alkaline water, while normal tap water has a PH of 7.

Photo by Frank Albrecht on Unsplash

by Charles Baker