Linking of West and East Flowing Rivers of Karnataka: Management of Surface Water and Groundwater in Drought Prone Areas

Out of the State's total drainage area of 1,88,830 sq km, the westerly drainage is 24530 sq km (12.99%). More than 58% of (3408 TMC) the total surface water resources of Karnataka flow towards west flowing river basins which occupy less than 20% of the total area of the State. Out of this total 2000 TMC of West flowing waters, 40% (800 TMC) of rain water designated as Submarine Ground Water Discharge (SGWD) flows along with fertile silt into the Arabian sea through porous fractured and weathered hard rocks and sediments leaving unutilised flow of 1200 TMC of water. The modalities of the diversion of the rivers earlier mooted by K.L. Rao who envisaged constructing a Ganga-Cauvery link Canal; Captain Dustur's suggestion of construction of a garland canal for Western Ghats Watershed, G.S. Paramashivaiah's report on diversion of "sea flowing rivers" to meet the drought prone seven districts of Karnataka; BWSSB Expert Committee Report on diversion of excess water of Sharavathi to Bangalore; and Madhu Seethappa's Quest to Abate Thirsts, a proposal of diversion scheme of Sharavathi-Aganashini-Bedathi; and current proposals of Yettinahole and Mahadayi river diversions are discussed in this paper. There are a large number of streams and rivers that initially flow eastwards and changes their course to west due to the uplift of Mysore Plateau and headward erosion. Mahadayi, Kali, Bedathi, Aganashini, Sharavathi, Varahi, Seeta and Netravathi river basins are the main catchment areas apart from the small river basins, which contribute to 2000 TMC of total quantity of surface and groundwater along with fertile silt and organic matter. With this in background Geological Society of India on 28.05.2015 held a Seminar on Integrated and Sustainable Water Management, to prioritize sustainable conjunctive use of water in command areas, charging of groundwater in lift irrigated areas for filling up water in dry tanks for utilization of the same for developing dry land areas with particular focus on recharging aquifers in dry land areas where there is acute shortage of water for drinking in drought affected areas. The objective of this paper is to identify micro basins and select a few west flowing streams and rivers from their upland catchment areas and link them to the eastern drainage for providing drinking water, recharge groundwater through filling of existing dry tanks and rejuvenate dead rivers in drought affected areas in Eastern Karnataka without affecting the biodiversity and environment of Western Ghats in any substantial fashion.