IIT Madras: Proposes to implement rapid groundwater recharge technology at Tirunelveli district

Indian Institute of Technology Madras Researchers has proposed implementing a rapid groundwater recharge technology for combined flood and drought mitigation near Ayankulam village in Thisayanvilai taluk of Tirunelveli district.

A proposal for this project has been submitted to the Tirunelveli district administration, which had requested IIT Madras to study this phenomenon.

A release for IIT-M on Friday said that an open agricultural well in Ayankulam was widely reported to recharge an estimated 1,500-2,500 liters of water every second for several weeks without overflowing. The recharge water for this well was from the excess overflow of an adjacent minor irrigation tank due to the record monsoon rains in Nov-Dec 2021.

The well became a local attraction and was called a “miracle well” since typical wells would fill and overflow in a matter of hours at such recharge rates. Local villagers have been practicing this ad-hoc method of well recharge during episodic intense monsoon years for several decades. They claim that this practice increased the local water table in a 10-15 [km] radius from the well.

The region surrounding this village is considered a dry belt with hot summers. Many small land-holding farmers have abandoned their farming practices and work as laborers in larger farms or other labor-based occupations. Being close to the coastal zone, several agricultural and domestic wells in the region suffer from saltwater intrusion due to excessive pumping and lowering of groundwater levels. Even extending the agricultural water availability by a few months each year can positively impact the livelihoods of these farmers.

The IIT Madras Team suggested implementing a ‘Rapid Recharge Technology,’ which, when developed, can bring several potential benefits to the region, including mitigating floods and droughts, creating a subsurface dam for water storage without evaporation loss, distributing water automatically and equitably throughout the region, filter and clean water when managed appropriately, and prevent and reverse saltwater intrusion in coastal aquifers.