Karst aquifers, the secret behind ‘miraculous’ well in Tamil Nadu's Ayankulam

TIRUNELVELI: An eight-month-long study conducted by an expert team from IIT Madras has revealed that the farm well at Ayankulam remained unfilled last December even when parts of Thisayanvilai taluk got flooded, as the well absorbed nearly 500-600 crore litres of water. 

In a statement, the district administration said the farm well is connected to limestone karst aquifers, which may have taken over 1,000 years to form. Assembly Speaker M Appavu and district Collector V Vishnu inspected the well on Monday. 

“The team dug 22 new borewells to collect soil samples. They found limestone deposits and underground streams during their study, which was initiated upon the Collector’s request. According to the study, 14 other nearby wells in Keeraikaranthattu, Sathankulam, Suvisheshapuram and Idaichivillai were found to be naturally linked with limestone karst aquifers,” the statement read.

The officials also noted that the Ayankulam farm well was more special than the other 14 wells, as it can be used to recharge the groundwater table in a 30-40 sq km radius. “While water in dams and other resources are prone to evaporation, underground water can be used by farmers whenever needed. Rainwater can be channelled to surrounding farm wells via underground streams, which will eliminate the need for an irrigation water-distribution system in Thisayanvilai region. This could also solve water sharing disputes,” the statement added, mentioning that the district administration would extend the area of the groundwater table to over 200 sq km.

IIT study finds 14 such wells in the region
The IIT Madras team found 14 other nearby wells in Keeraika-ranthattu, Sathankulam, Suvisheshapuram and Idaichivillai, which are naturally linked to limestone karst aquifers. But the Ayankulam farm well is special as it can recharge the groundwater table in a 30-40 sq km radius.