Hydrogeological characterization of the Quaternary aquifer of south Bengal Basin in India and the impact of urbanization on the groundwater resources of the system

Understanding the Past-Present-Future Hydrogeologic System Through Numerical Groundwater Modeling of South Bengal Basin, India

“…In the Ganges-Brahmaputra and Indus basins, the groundwater abstraction exceeds the potential groundwater recharge at the rate of ∼246 km 3 /year (CGWB, 2006). Over-withdrawal of groundwater causes problems such as land subsidence, deterioration of water quality, saltwater intrusion, decline of the piezometric surface, and increased pumping costs (Sikdar et al, 1996;Hoque et al, 2007;Galloway and Burbey, 2011;Hosono et al, 2011;McDonald et al, 2011;Sahu andSikdar, 2011, 2017;Banerjee and Sikdar, 2021). The deterioration of groundwater is more obvious for countries such as India, having more than 17% of the global population but only 2.5% of its geographical area (Patra et al, 2018;Banerjee and Sikdar, 2021).…”

“…Over-withdrawal of groundwater causes problems such as land subsidence, deterioration of water quality, saltwater intrusion, decline of the piezometric surface, and increased pumping costs (Sikdar et al, 1996;Hoque et al, 2007;Galloway and Burbey, 2011;Hosono et al, 2011;McDonald et al, 2011;Sahu andSikdar, 2011, 2017;Banerjee and Sikdar, 2021). The deterioration of groundwater is more obvious for countries such as India, having more than 17% of the global population but only 2.5% of its geographical area (Patra et al, 2018;Banerjee and Sikdar, 2021). In India, the unsystematic urban sprawl, fast growth of population, and expedited speed of industrialization create immense stress on the hydrogeological resources (Foster, 1988;Yisa and Jimoh, 2010;Patra et al, 2018;Banerjee and Sikdar, 2021;Ram et al, 2021).…”

“…The deterioration of groundwater is more obvious for countries such as India, having more than 17% of the global population but only 2.5% of its geographical area (Patra et al, 2018;Banerjee and Sikdar, 2021). In India, the unsystematic urban sprawl, fast growth of population, and expedited speed of industrialization create immense stress on the hydrogeological resources (Foster, 1988;Yisa and Jimoh, 2010;Patra et al, 2018;Banerjee and Sikdar, 2021;Ram et al, 2021). This is coupled with the majority of the Asian cities not having any groundwater policy to protect the stressed aquifer and remediate contaminated aquifer.…”

“…As a result, several million handpump-fitted wells and heavy-duty motor wells were installed to meet the demand for drinking, irrigation, and industrial purposes (Smith et al, 2000;BGS/DPHE/MML, 2001;Horneman et al, 2004;Harvey et al, 2005). The aquifer of the South Bengal Basin in West Bengal (India), located in the lower deltaic plain of the River Ganges, also is subjected to huge stress as a result of over-exploitation of groundwater due to rapid population growth and increase in urban sprawl (Banerjee and Sikdar, 2021).…”

“…The aquifer beneath two of the fast-growing megacities of the South Bengal Basin-Kolkata and Howrah-has been experiencing quality deterioration, lowering of piezometric surface, change of groundwater flow direction, expansion of groundwater trough, and change of aquifer behavior on a local scale (McArthur et al, 2018;Banerjee and Sikdar, 2021) due to the increase of built-up area and reduction of wetland and vegetation cover (Mukherjee et al, 2018). The estimated groundwater overdraft in 2016 is 408 × 10 3 m 3 /day, which lowered the piezometric surface by 34 cm within the study area, whereas the long-term decline of water levels is 13-37 cm/year (Banerjee and Sikdar, 2021). As a consequence, Kolkata and Howrah of the South Bengal Basin are moving toward an obvious water crisis.…”