An artesian well is one that is connected to an accumulation of water whose piezometric level is above the surface of the well. This means that the upper limit of the aquifer is higher than the opening through which the liquid exits the artesian well.
For this reason, the main peculiarity of an artesian well is that the water gushes out by itself without the need for pumping. The area where the body of water is located is known as the water table. The accumulation of water itself is between two waterproof layers.
The fact that the liquid is contained between impermeable layers makes it compressed, so the pressure is usually high. Said pressure is also due to the effect of height with respect to the well opening. Artesian systems can also contain water at high (thermal) temperatures.
Artesian wells have several peculiarities. In the first place, the cavity where the water goes has a great inclination and the walls of said cavity are waterproof.
The water enters as a result of the rains through the upper sloping end. In this case, there must be a certain permeability so that the mass of the rainwater enters and agglutinates towards the bottom. In this way, a high pressure is generated as a result of the weight of the liquid itself.
The hole where the water will come out should be located towards the lower sloping part. Then, it must be drilled towards the upper wall of said lower oblique end.
The waterproof character of the rocks that make up the edges of the concavity is due to their compact nature. In addition, for the well to function properly, the presence of heavy rains permeating towards the upper end of the sloping concavity is required at some time of the year.
Most of these conditions are usually found in valleys. Likewise, when drilling the curb of the well, the liquid usually comes out at very high pressure, and the water even rises several meters above the ground.
There are also so-called artesian springs. In these the principle of the accumulation of the water mass is similar; however, the liquid exits to the surface through holes that have formed in the layers of impermeable rock.
In summary, an artesian well has the following characteristics:
– It is made up of a sloping concavity under the ground.
– The walls of the concavity are made up of compact rocks of an impermeable nature.
– The water that enters is the product of the rains.
– The perforation to extract the water goes in the lower part and the weight of the liquid induces its high pressure.
Building an artesian well is often an excellent solution. These offer advantages such as the fact that the depth of the water level is usually known in advance.
Also, these wells can supply large amounts of water and do not require pumping equipment. Artesian water does not require equipment to clean the liquid due to its purity and the fact that it is not exposed to contaminants.
How is it built?
Previous surveys are often required to determine the presence of the aquifer or to search for ecological documents. Topographic maps also give good information in this regard.
A license is often required for exploration and the costs are high as it must be done by a company. On the other hand, if the depth of the well exceeds 7 meters, the excavation would have to be carried out with a drill.
Wells with depths greater than 30 require certain permits for extraction. Additionally, there would be the considerations regarding the pipes; these are recommended made of polymers and plastic when the depth is shallow.
Steel ones are an excellent option for greater depths, but the use of welding should be avoided due to the effects of corrosion.
Artesian wells are usually drilled with drills; the diameter of the initial hole must be greater than that of the pipe. The excavation must be done away from possible contaminants.
The tubes can be pushed by hand when it is shallow, if appropriate mechanical equipment is not required. Deep drilling can be done with rotaries or hammers.
Swivel and percussion cables can also be used, as well as water jets.
Finally, once the hole has been dug and the water level connected to the surface by means of a pipe, additional protection elements would have to be installed. In this case we refer to covers to prevent the entry of contaminants and protect the installation itself.
Differences between an artesian well and a normal well
The essential difference between an artesian well and a normal well is that in the former the water gushes on its own, even under pressure. On the other hand, in a normal well, some type of mechanism is required, either manual or pumps, to extract the water.
Artesian wells typically provide a much purer water quality that generally does not require treatment. Additionally, these tend to have longer lifetimes and supply greater amounts of water than a normal well.
In most cases, there is prior knowledge of the existence of aquifers from artesian wells; these are usually documented in the geological field.
Everything related to water wells is an exciting and vital topic for the human being. This is due to how essential this liquid is for the subsistence of the species.
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