Recharge of deep borewells in hard rock terrain

India's dependence on the underground aquifer especially deep bore wells are well known. With over 22 million wells India has perhaps one of the largest such structures in the world. Since most of peninsular India is hard rock with basalt/granite/gneiss underlying they present a particular challenge for understanding. A series of experiments are on in Bangalore to determine what is the possible rate of recharge in some of these deep bore wells (depth greater than 150 feet) in hard rock terrains. This is primarily with a view to recharge these bore wells using filtered rooftop rainwater especially in urban areas. In Bangalore there are an estimated 200,000 bore wells and half of them are believed to have yielded well and are now non-yielding . The video demonstrates a recharge/slug test for one such bore well which has now stopped yielding water after 3 years - one day suddenly - as is usual with such bore wells in Bangalore. Add your suggestions to take this forward in the comments section!