Abstract: The water levels in Krishna Raja Sagara (KRS) reservoir depended mainly on the southwest monsoon over Karnataka, especially at the Cauvery catchment area and its inflow. The Krishna Raja Sagara (KRS) reservoir with the gross capacity of 49.45 thousand million cubic feet (tmc ft) and maximum water level is 124.8 ft that quenches major cities of Bengaluru, Mysuru, Mandya and other 47 towns and 625 nearby villages for their daily needs. With water levels drastically receding during extreme hot conditions in the Cauvery basin, Bengaluru is more likely staring at severe drinking water shortage. Water scarcity issues may arise in upcoming years due to its demand especially in industrial sectors of Bengaluru city, low rainfall conditions, rapid evapo-transportation due to extreme summer seasons and global warming (?). The present work deals with the utilization of GIS based Analytical Hierarchy Process (AHP) technique to delineate best sites to modify surface run-off through limited field visits. SoI toposheet, IRS-LISS-III and ASTER DEM data are collected to achieve present aim. All the important thematic layers have been digitized and overlaid one above the other to produce desired output in GIS environment. Each generated thematic maps have been assigned suitable weightages using AHP depending on the features priority to derive suitable sites for groundwater augmentation. The final results highlight the best sites for Artificial Recharge Structures (ARS) in decision making process which is a suitable model for similar geological terrain using AHP approach.

Keywords: Krishna Raja (K.R) Nagara; LISS-III; Geospatial Technology; ARS; AHP.

| DOI: 10.17148/IARJSET.2021.8768