Eighty percent of borewells fail due to unscientific methods in determining where to dig, according to hydrogeologist Devaraja Reddy NJ. Speaking at the Jalapatha symposium held at Cauvery Bhavan, Reddy explained that while there was once a regulation limiting borewell depth to 25 metres, these wells are now being drilled as deep as 600 metres (approximately 2,000 feet). The symposium, organized by the Bengaluru Jalamandali Abhiyantarara Sangha, aimed to raise awareness about water conservation and management.
Reddy, a hydrogeologist from Chitradurga, discussed sustainable alternatives to reduce the city’s dependency on borewells, emphasizing the importance of rainwater harvesting and recharging existing borewells. He stressed the urgent need for these solutions, highlighting that India receives around 1.12 lakh crore cubic metres of rainfall annually, while the demand is roughly 71,000 crore cubic metres. Despite this, much of the rainfall goes unused. “Bengaluru receives over 900 mm of rainfall annually, and if we focus on recharging borewells and harvesting rainwater, we can make a huge difference,” Reddy said.
Having drilled 25,000 borewells in his career, Reddy now focuses on replenishing the water extracted. He pointed out that 80% of aquifers in the region have been depleted, with the remaining 20% located in areas with little human interference. He also suggested exploring desalination projects, similar to Chennai’s desalination plant in Mangaluru, as a potential solution. “North Chennai receives 25% of its water supply from desalination, at a cost of about 22 paisa per litre,” he noted.
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