NEW DELHI : The central government plans to recharge groundwater using treated water as part of a new attempt to alleviate water shortages in Tamil Nadu. If the pilot proves successful, the method will likely be replicated in other parts of the country as well.
Lack of fresh water to recharge groundwater is a problem in large parts of Tamil Nadu where saline seawater has seeped into the ground rendering it infertile.
The artificial recharge project is being implemented in collaboration with the Netherlands, according to the department of water resources, river development and rejuvenation of the Ganges under the Jal Shakti ministry.
The pilot project implemented in Araniyar and Korattailaiyar river doab in Tamil Nadu is an innovative solution, the department said. Doab refers to the alluvial land between two converging rivers.
“In India or any other country, direct recharge from treated water has not been adopted as groundwater is used for all purposes including consumption. The area has already been affected by seawater intrusion and the groundwater is already saline. Considering the poor groundwater quality, it would be wise to conduct a pilot study in this area and understand the impact through vigorous monitoring and based on the results, the same can be replicated in other areas. having similar issues,” the department said.
According to a 2018 estimate by Niti Aayog, 600 million people in India face high to extreme water stress, and an estimated 200,000 people die each year due to insufficient access to safe drinking water, a crisis that is expected to get worse.
The water situation in states such as Rajasthan, UP and Gujarat is also of concern according to government estimates. Niti Aayog predicted that by 2030, India’s water demand will double the available supply. The policy think tank released a water management index in 2019 which ranked Gujarat as the best performer in 2016-17 and Jharkhand as the worst. He also projected that India’s water requirement by 2050 under a high-use scenario would likely be 1.18 trillion m3. m (BCM) while availability is likely to be less than 1,137 BCM.
“The natural way to purify rainwater and polluted surface water is to harvest it and turn it into groundwater. Government and NGOs should focus on reducing the cost of projects and magnifying the benefits and success of groundwater recharge through adequate knowledge of geological conditions,” said Rahul Todmal, Assistant Professor of Geography at the University of Pune.
An attempt was made earlier by the government of Tamil Nadu to push the seawater interface seaward by injecting fresh water into the aquifer, but this was halted due to non- availability of freshwater sources, the department said.
The Central Ground Water Board simulation suggested a possibility of positive impact from artificial recharge.