Application of geospatial modeling in deciphering groundwater recharge site and structures in Paschim Medinipur district, India

Abstract

Indiscriminate urbanization and population explosion have put tremendous stress on groundwater resource of Paschim Medinipur, an agriculture-dominated area. In this aspect delineation of potential groundwater recharge zones can play a crucial role in the long run. Initially, ten different influencing factors i.e., geology, geomorphology, rainfall, aquifer material, drainage density, soil type, lineament and fault density, slope, elevation and Land use land cover (LULC) are integrated into ArcGIS environment to generate the potential groundwater recharge zones (GWRZ) within the study area. The final GWRZ was categorized into three classes namely high, medium and low where about 33% (3152.46 sq. km) of the total area fall under high GWRZ, about 25% (2379.02 sq. km) is covered by medium GWRZ and low GWRZ covers about 39.96% (3743.16 sq. km) of the study area. Predicted model is validated with water table fluctuation data collected from 87 monitoring wells by implementing Success Rate Curve (SRC) and the Prediction Rate Curve (PRC) where an accuracy of 81% prediction is observed. The study of WTF trend for past 23 years using the multiplicative model of time series shows a significant declining trend in-depth to water-table. Based on the model outcome various recharge structures are recommended in the specific locations of the study area which may be further confirmed through field investigation before implementation. Outcomes of the present study can be a first-hand tool to the policymakers, planners and government officials for sustainable water resource management in the study area.