Groundwater sustainability in the Varuna river basin: impacts of climate change and population growth

This study uses the SWAT model combined with bias-corrected climate projections across four SSP scenarios to assess the impacts of climate change and population-driven water demand on groundwater sustainability in the Varuna river basin (VRB). Climate anomaly analysis revealed a significant decrease in precipitation and an increase in temperature under higher emission scenarios (SSP370 and SSP585), intensifying recharge drought conditions and evapotranspiration rates. Using Anselin's Local Moran's I method, we identified distinct spatial patterns of groundwater recharge. The low-emission scenario showed a stable recharge distribution (SSP126), whereas higher-emission pathways revealed extensive clusters of recharge hotspots and coldspots, indicating regional disparities in recharge. Additionally, the analysis of the groundwater sustainability ratio (GSR) dynamics showed intensified over-exploitation risks in SSP585, which were driven by reduced recharge and higher atmospheric water demand. These findings highlight the necessity for adaptive water management strategies to address climate-driven recharge disparities and enhance groundwater sustainability in the VRB through artificial recharge.