3-Dimensional Hydrogeological Flow Model Using Visual MODFLOW for Kulhan Nala in Kharun River Basin at Raipur, Chhattisgarh

The quantity of water in groundwater resource is of major concern these days. To overcome these issues, scientific methods and proper analysis needs to be carried out. Real groundwater system is dynamic in nature. To enhance understanding physical processes in subsurface zone, modeling technique is widely used. The Visual MODFLOW, which is one of the groundwater modeling tool has been explored in this study to locate the ground depletion zones in a small sub-basin namely, Kulhan nala which is about 942 km2 located in Raipur district in Kharun River basin. For this purpose, simulation of hydraulic head over an area carried out by taking previous years of variable data collected from different sources. Model has been assigned appropriate boundary type based on natural condition of study area. An unconfined aquifer having soil cover and underlying litho units are considered to be single layer for transient simulation of hydraulic head. The calibration of model involves interactively adjusting the model input data through a trial and error process to align the model’s output with observed data. The results show that the performance of the developed model is working well in identifying the groundwater depletion zone with the RMSE value of 3.4 m and R = 0.96 during calibration and RMSE value of 3.9 m and R = 0.98 during validation. The created flow model has provided insights into the direction of groundwater flow, water budget, and changes in hydraulic heads in response to applied stresses such as groundwater abstraction and rainfall recharge. The results of the model can be used as a scientific foundation to help water resource managers and policymakers make well-informed decisions and create sustainable groundwater management plans.