Groundwater modelling using an analytic element method and finite difference method: An insight into Lower Ganga river basin

Abstract

Groundwater flow modelling provides the water flow dynamics for the estimation and prediction of groundwater movement and its condition in the aquifer. The modelling helps for the management of the groundwater resources under various hydrological and anthropogenic stresses. In this paper, a modelling exercise was performed using the analytic element method (AEM) and finite difference method (FDM) for the part of Ganga river basin which includes the Varanasi district. Further compression was performed to understand the limitations and benefits of both AEM and FDM based on ease of model development, data requirement and their performances. The groundwater model was developed for the transient state condition based on data for the year 2004-2017. The results show that for most of the observed wells, the difference between the observed head and the simulated head is found in the 90% confidence level. It is found that the AEM does not require a fixed boundary condition which makes the development of the conceptual model less complicated. In the FDM, pumping wells are approximately located and averaged over the cell which becomes a cause of the inaccurate location of the wells. It is found that model development in the AEM is less complicated compared to the FDM. It can be concluded that in some cases AEM-based modelling is more accurate as compared to FDM-based flow modelling. This study can be very helpful for groundwater professionals in deciding the best suitable method for their study area and to avoid the complexity of the model.

Groundwater Level Assessment in an Alluvial Aquifer Using Neural Networks

“…For the simulation of GW variations in the past, ANN models were used. ANN demonstrating has previously been used to mimic water table variations in several places [2,3,7,10,11,16,18,19,31,32]. These studies show that ANN models can be helpful in forecasting water table fluctuations, especially in areas where water cycle parameter records are scarce or non-existent.…”

“…Drought and depletion of groundwater reserves may result from excessive water use. Many communities are currently experiencing changes in the pattern of land [16,17,18], changes in the way of river Ganga [20,21,22,23,26,27] and rapid depletion in the level of GW due to high increase in population, which was 1.21 billion in 2011 as compared to 1991 (Census of India). Prior to overexploitation and poor groundwater management, groundwater was efficiently available to meet various daily demands; however, the groundwater table has been lowered in many regions [16,17,23,25].…”

Groundwater Potential Zone Delineation Using Multi-criteria Decision-making Approach: A Case Study

“…To learn about the characteristics of the ground surface, DEM data from the SRTM was used. DEM data was projected to the World Geodetic System 1984 (WGS, 1984) of the global reference system and the Universal Transverse Mercator (UTM) Zone-44N coordinate system (Omar et al, 2019). The Indian Meteorological Department provided rainfall statistics.…”

Wavelet gated multiformer for groundwater time series forecasting

“…Numerous approaches have been proposed for modeling, simulating, and predicting groundwater levels using conceptual models 15 , finite difference 16 , and finite element 17 , 18 approaches. Although classical models can be reliable for predictions, large volumes of data are necessary.…”