Drainage morphometry and groundwater potential mapping: application of geoinformatics with frequency ratio and influencing factor approaches

Abstract

Morphometric analyses have the ability to provide substantial evidences of drainage evolution, hydro-geomorphic, denudation, and tectonic characteristics that are essential for sustainable watershed management and planning. The aim of this study is to investigate different morphometric parameters and groundwater potentials in Savitri and Vashisthi basins though geographic information system (GIS) techniques. Utilizing high-resolution satellite images, conventional datasets, and relevant field data, we prepared eight thematic layers that regulate the groundwater potentials of an area, such as geology, lineaments, drainage density, slope, rainfall, soil texture and depth, and well density. All these conditioning factors were analyzed in GIS using weighted sum method utilizing the influencing factor (IF) and frequency ratio (FR) methods to prepare the groundwater potential maps. The resultant groundwater potential maps were classified into four sections of different potentiality as: very high, high, moderate, and low. The accuracy of these groundwater potential maps was confirmed by area under the curve (AUC) through establishing a relationship between cumulative percentage of different groundwater potential classes and cumulative percentage of the availability of wells. Prediction of groundwater potentials through FR showed pronounced efficiency (AUC = 75%) for both drainage basins compared to the IF technique (AUC = 69% and 65% for Savitri and Vashisthi, respectively). It was summarized that the reliability of FR technique is higher, contrasting to the IF technique for groundwater potential mapping in our study area. Moreover, morphometric parameters indicated that the drainage development is highly mature in both catchments. The resultant groundwater potential maps can be used for sustainable water resource management and developing artificial recharge projects in the study area.