In this study, an integrated spatial framework approach has been developed by combining GIS-based Multi-criteria Decision Analysis (MCDA), the DRASTIC model, SCS-Curve Number-based runoff estimation with field-based measurements to delineate optimal (highly suitable) recharge zones in a semi-arid drought prone basaltic aquifers of the Godavari River Basin (GRB), Western India, for sustainable groundwater development. A total number of twenty-three variables across five categories (hydrological, morphological, soil, land cover and social parameters) were spatially downscaled for rainfall and resampled for remaining variables at a grid resolution of 1 × 1 km for demarcation of the Groundwater Potential (GWP) and Groundwater Vulnerable (GWV) zones using the Fuzzy AHP (a GIS-based MCDA) and the DRASTIC model, respectively. The accuracy of the generated GWP and GWV maps was validated using ROC curves. Further, the runoff potentiality in 70 sub-basins was evaluated using the SCS-CN method. A composite groundwater development suitability map, prioritising zones with high availability, low vulnerability, and high recharge likelihood, was prepared by overlaying the GWPZ, GWVZ, and runoff potential maps. Only 3.6% (~ 2036 km 2 ) of the total catchment area of which 70% is in the drought-prone districts is found to be highly suitable for groundwater development. The accuracy of the highly suitable recharge sites ( n = 7) was also validated through field-based infiltration tests and visual inspections. It mainly covers north-eastern, central and south-eastern part of the basin where groundwater flow lines have generally converged. The integrated framework not only enhances the spatial precision but also enables risk-informed groundwater planning in the GRB, thereby making a direct contribution to the United Nations’ Sustainable Development Goals (SDGs) 3 and 6.
Karan et al. (Tue,) studied this question.