What is 'Artesian Condition'?

Why in the NEWS?

• Recently, water is leaking from beneath the ground in a village in Rajasthan.
• Dr. Narayan Das Inakhia, Senior Hydro-Geologist of Rajasthan State Ground Water Department, blamed 'Artesian Condition' for this incident.

Key Points:

• Geological incident that took place on 27th December in Taranagar village of Jaisalmer district of Rajasthan.
• On 27th December 2023, a large amount of water started emerging from the ground in Taranagar village of Jaisalmer.
• This incident happened when a farmer had hired a firm to dig a tube well up to 850 feet to extract water.
• After digging, water started flowing with high pressure in about an hour.
• The water pressure was so high that a truck and drilling machine also got stuck.
• A small amount of non-flammable gas also started coming out with the water.
• A large crater was also formed due to the high pressure of water.
• Similar conditions have been seen previously in desert regions of Australia and Africa.

What is an Artesian Condition?

• Artesian condition is a geological phenomenon that occurs when groundwater seeps spontaneously from a closed or compressed reservoir to the earth's surface.
• This reservoir is located between two impermeable layers that hold the water.
• When this reservoir is damaged at a place or the pressure there is low, the water comes out without any pressure from an external source.
• This process is called "artesian flow".

Main causes of Artesian Condition:

• Constriction of the reservoir (aquifer): 
  • Artesian condition occurs when water is trapped in a compressed reservoir.
  • These reservoirs are usually located between two hard rocks or layers that do not allow the water to escape.
• Pressure on the upper layer: 
  • There is an external pressure on the water in the reservoir. 
• When this pressure becomes too great, the water begins to seep upward on its own, creating artesian conditions.
• Natural passage of groundwater: 
  • In artesian conditions, there are sometimes cracks in the layers above the reservoir, which allow water to seep out naturally.
• Flow of artesian water:
  • When artesian conditions are formed, water comes out on its own to the surface or from a well, tap or other water source.
  • This natural flow often occurs when too much water has accumulated in an underground reservoir, or when underground layers (such as soil or rocks) break down and the water finds a way out.

Advantages and disadvantages of artesian conditions:

• Advantages: 
  • Water comes out spontaneously during this process, allowing water sources to be used without any external pumping.
• Disadvantages: 
  • Sometimes this situation comes in the form of subsidence, which may lead to flooding, drainage or pollution of other water sources.