Groundwater potential assessment using an integrated AHP-driven geospatial and field exploration approach applied to a hard-rock aquifer Himalayan watershed

• Published in: Journal of hydrology. Regional studies Vol. 37; p. 100914
• Main Authors: Sapkota, Sanjib, Pandey, Vishnu Prasad, Bhattarai, Utsav, Panday, Suman, Shrestha, Surendra Raj, Maharjan, Sudan Bikash
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.10.2021; Elsevier
• Subjects: Analytical hierarchy process (AHP); aquifers; electrical resistance; Electrical resistivity tomography (ERT); GIS & RS; groundwater; Groundwater potential; Hard-rock aquifer; Himalayan region; Nepal; Nepal Himalaya; tomography; watersheds; Himalayan region; Nepal; Electrical resistivity tomography (ERT); GIS & RS; Nepal Himalaya; Groundwater potential; Analytical hierarchy process (AHP); Hard-rock aquifer
• ISSN: 2214-5818; 2214-5818
• DOI: 10.1016/j.ejrh.2021.100914

[Display omitted] •This is one of the very few studies of this kind in the Nepal Himalaya.•Six indicators representing various aspects of groundwater potential were selected.•A simplistic two-step validation strategy using spring-discharge & ERT was applied.•Lithology and lineament density were found to be the most influencing indicators. Eastern Nepal, The Himalayas. This research is aimed at delineating groundwater potential zones in a hard-rock aquifer Himalayan watershed integrating geo-spatial and field exploration techniques. A customized indicator-based weighting method, consisting of six indicators, was developed and applied in the study watershed. Spatially-distributed maps for the indicators were produced based on information from primary as well as secondary sources. The indicators were further aggregated and groundwater potential map was prepared using relative weights derived from Analytical Hierarchy Process with inputs from key hydrogeology experts. The map was then validated using observed data of springs as well as results from Electrical Resistivity Tomography (ERT). The novelty of this study lies in the application of two-step validation (using springs data from the field and ERT) of the groundwater potential mapping approach which demonstrates the robustness of the overall methodology for data scarce regions and paves way for its wider applicability in decision support for groundwater exploration activities. Further, this is one of the very few groundwater potential studies in the Nepal Himalaya hydrogeological setting.