Prioritization of Watershed for GWPZ Through Remote Sensing, GIS and Integrated Weighted Sum Approach: A Case Study of Dhodana River Basin, Central India

Abstract

The Dhodana watershed is a part of Deccan Volcanic Province (DVP) of central India. The basalt lava flows of the area are of simple aa type and forms a multi-layered aquifer system due to alternate hard massive and vesicular units which creates heterogeneity uncertainty of groundwater occurrence. The hydrogeological field data acquired during field operations was taken into account to create an accurate picture of groundwater availability. The results show that static water levels range between 4.58 mbgl to 18.6 mbgl in pre-monsoon season and between 0.1 mbgl to 15.5 mbgl in post-monsoon season. The seasonal water level fluctuation ranges between 2 mbgl to 7.93 mbgl. Similarly yield of the dug wells in pre-monsoon season ranges between 4500 litre/day to 1,97,100 litre/day and in the post-monsoon season ranges between 36,000 litre/day to 5,40,000 litre/day. Thematic maps like lithology, geomorphology, soil, slope, land use-land cover, lineaments were taken into consideration with appropriate weightages, according to their contribution for groundwater occurrence. The remote sensing technique and GIS softwares were utilized for this purpose. The watershed was divided into five categories, based on their respective weightages as: very good, good, moderate to good, poor to moderate and poor groundwater potential zones. This result shows that the area of very good and good groundwater potential covers 6% and 24% watershed area, which is mostly under storage zone; moderate to good and poor to moderate GWPZ covers 33% and 23% area of the watershed in the runoff and recharge zones. The area of poor groundwater potential covers 14 % of the watershed in the runoff zone. It is also observed that groundwater potential is almost same along river and drainage banks.