Chapter 7 - Delineation of groundwater potential zones in the hard rock terrain of an extended part of Chhotanagpur plateau applying frequency ratio (FR) model

Abstract

Scientific mapping of groundwater potential zones is highly required for unprecedented urban and rural growth and industrial expansion, particularly in Chhotanagpur hard rock terrain. The principal objective of this study is to identify the potential pockets of groundwater applying frequency ratio (FR) model. Different significant factors such as land use land cover, lineament, rainfall, soil texture, slope, drainage density, groundwater fluctuation, geology, hydrogeomorphology have been carefully considered for this investigation. We considered 56 tube wells for better performance, particularly in this study area. Out of 56 tube wells, almost 70% and 30% have been used as a training and testing samples, respectively, for the FR model. Finally, groundwater potential zone map has been classified into five categories, such as very high, high, moderate, low, and very low. Results show that the very low groundwater potential zone is confined in the southwestern part (Arsha, Bagmundi, and Jhalda block), whereas very high is found in southern (Bandwan and Manbazar II block) due to favorable geological and good soil conditions. The percentage of the accuracy of FR model is 79.1% which indicates a good prediction rate. This scientific model can assist to regional planners and policymakers for sustainable groundwater development and management.