Groundwater Depletion Signatures in Southeastern Karnataka

Groundwater level data for 1909 and 2004 evince marked but non-uniform groundwater depletion in . southeastern Karnataka. Over the century period, vertical depletion is distinct in the fractured regional aquifer system, mainly in four zones or nadirs. Out of these four, the zone.discharging into Palar basin on the southwest of Kolar schist belt shows widest nadir of groundwater depletion.

Deep mining at Kolar Gold fields over a prolonged period induced deep fractures that facilitated massive migration of groundwater to deeper levels by viscous flow. It is estimated that in deeply fractured zones like KGF, the quantity of groundwater accumulated annually is about 0.4 MCM/km² whereas the average annual rainfall recharge in the average surrounding area is only about 0.09 MCM/km².

The groundwater suction effect in KGF mines and further transfer of groundwater laterally into the highly Fractured discharge zone of low lying river basins, along shear zones and major fractures, appears to be primarily responsible for the severe lowering of groundwater in the region.