TY - JOUR
T1 - Demystifying the decadal shift in the extent of groundwater in the coastal aquifers of Gujarat, India
T2 - A case of reduced extent but increased magnitude of seawater intrusion
AU - Kumar, Manish
AU - Panday, Durga Prasad
AU - Bhagat, Chandrashekhar
AU - Herbha, Nilkanth
AU - Agarwal, Vivek
N1 - Funding information: This work is partially funded by Climate Change Department of Gujarat State Government, India, and Seed project funded by UPES. We wish to thank Prof. Vikrant Jain for the administrative support.
PY - 2023/11/10
Y1 - 2023/11/10
N2 - Catastrophic increase in urbanisation and industrialisation along the coastal region leads to increased stress on groundwater reservoirs worldwide. As a growing economy, India faces extreme water crises due to rising water demand and escalating salinisation, specifically in the coastal districts. Therefore, this study shows the implication of a comprehensive modelling approach to assess the spatiotemporal changes in hydrogeochemical processes in the coastal aquifer of the Surat district. Using a multi-model assessment approach, the present study focuses on the decadal evolution in groundwater quality of the coastal aquifers of Surat, Gujarat. Fifty-one groundwater samples were collected for 2008, 2012, and 2018 to assess the spatio-temporal shift in groundwater quality. Piper diagram revealed a shift of hydrogeochemical facies from Mg
2+-HCO
3
− type to Ca
2+-Mg
2+-Cl
− type, indicating the increased salinisation over a decade. The result suggests that rock-water interaction, seawater intrusion mechanism, and anthropogenic activities (intensive agricultural activities and improper waste management) govern the hydrogeochemical processes in the coastal aquifer. A shift of dominance of carbonate weathering to silicate weathering with the dissolution of calcite, dolomite, and gypsum, changing the hydrogeochemistry, was observed over the last decades. This shift leads to the increasing hardness of groundwater. The enrichment of nutrients in groundwater during 2018 (NO
3
− = 2 to 85 mg. L
−1) compared to 2008 (NO
3
− = 1 to 36 mg.L
−1) indicates the increasing imprints of agricultural fertilizer application and human organic waste through sewage contamination on the coastal aquifer. The seawater mixing index model demonstrates that extent of seawater intrusion reduced in 2018 compared to 2012, but the magnitude increased near the coastal talukas (SMI =9.5). The present study helps to understand the increasing anthropogenic activities over a decade leading to increased salinisation and groundwater contamination in the aquifer system. This work can help local stakeholders, water resource managers, and the state government manage the groundwater resources and the future potential threat of aquifer contamination.
AB - Catastrophic increase in urbanisation and industrialisation along the coastal region leads to increased stress on groundwater reservoirs worldwide. As a growing economy, India faces extreme water crises due to rising water demand and escalating salinisation, specifically in the coastal districts. Therefore, this study shows the implication of a comprehensive modelling approach to assess the spatiotemporal changes in hydrogeochemical processes in the coastal aquifer of the Surat district. Using a multi-model assessment approach, the present study focuses on the decadal evolution in groundwater quality of the coastal aquifers of Surat, Gujarat. Fifty-one groundwater samples were collected for 2008, 2012, and 2018 to assess the spatio-temporal shift in groundwater quality. Piper diagram revealed a shift of hydrogeochemical facies from Mg
2+-HCO
3
− type to Ca
2+-Mg
2+-Cl
− type, indicating the increased salinisation over a decade. The result suggests that rock-water interaction, seawater intrusion mechanism, and anthropogenic activities (intensive agricultural activities and improper waste management) govern the hydrogeochemical processes in the coastal aquifer. A shift of dominance of carbonate weathering to silicate weathering with the dissolution of calcite, dolomite, and gypsum, changing the hydrogeochemistry, was observed over the last decades. This shift leads to the increasing hardness of groundwater. The enrichment of nutrients in groundwater during 2018 (NO
3
− = 2 to 85 mg. L
−1) compared to 2008 (NO
3
− = 1 to 36 mg.L
−1) indicates the increasing imprints of agricultural fertilizer application and human organic waste through sewage contamination on the coastal aquifer. The seawater mixing index model demonstrates that extent of seawater intrusion reduced in 2018 compared to 2012, but the magnitude increased near the coastal talukas (SMI =9.5). The present study helps to understand the increasing anthropogenic activities over a decade leading to increased salinisation and groundwater contamination in the aquifer system. This work can help local stakeholders, water resource managers, and the state government manage the groundwater resources and the future potential threat of aquifer contamination.
KW - Speciation modelling
KW - Contamination
KW - Seawater intrusion
KW - Hydrogeochemistry
KW - Gujarat coast
KW - Groundwater quality
UR - http://www.scopus.com/inward/record.url?scp=85165640410&partnerID=8YFLogxK
U2 - 10.1016/j.scitotenv.2023.165451
DO - 10.1016/j.scitotenv.2023.165451
M3 - Article
C2 - 37451470
SN - 0048-9697
VL - 898
JO - The Science of the Total Environment
JF - The Science of the Total Environment
M1 - 165451
ER -