Towards Sustainable Groundwater Management: Predicting Deformation Scenarios with Coupled Hydrogeophysical Models

Land subsidence due to groundwater extraction can cause a permanent loss of groundwater storage, and thus mitigating this is crucial for sustainable groundwater management. One challenge in effective mitigation is accurately predicting the effect of groundwater pumping on land deformation due to uncertainty in subsurface hydrostratigraphy. In this study, we demonstrate how a coupled hydrogeophysical model, combining geophysical and InSAR data, can improve estimates of subsidence by providing information about the subsurface layers that are deforming. Using this model, we estimate future scenarios of subsidence, and the potential of managed aquifer recharge for reducing subsidence. We find that if no management changes are made, roughly ~2 m of subsidence will occur from 2019 to 2038, but that active managed aquifer recharge could reduce land subsidence by as much as ~4 m. This model can enable water managers to mitigate subsidence by prioritizing areas for managed aquifer recharge.