Balancing groundwater access and sustainability through energy pricing in India

Pumping energy is a key component of the groundwater governance challenge. Yet it is largely missing in the discourse on agricultural use of groundwater. A sub-category of literature studying groundwater-energy nexus tends to focus on groundwater depletion hotspots where entrenched interests and long-standing history restrict the range of feasible energy models. We simulate expected impacts of expanding groundwater irrigation under five different energy provision models in a region with among the lowest irrigation coverage, and therefore, free of path dependent policies. We find aquifer properties play a crucial role in mediating the groundwater-energy nexus. On average, the maximum volume of water that can be pumped from a well of a specific depth in an alluvial aquifer is approximately 150 times the volume that can be pumped from a well in a hard-rock aquifer. Therefore, managing uncertainty in groundwater consumption is a far greater challenge in alluvial than hard-rock aquifers. Uncertainty in groundwater consumption can be limited in hard-rock aquifers if the number of wells and depths of wells can be controlled - capital subsidies for well construction could be a potential policy. Our results imply that while solar pumps are a risky alternative in alluvial aquifers for maintaining current and future groundwater levels, they are relatively safe and among the most economical for expanding irrigation in hard-rock regions. Using a novel dataset comprising of biophysical and socioeconomic data, we find hard-rock regions to have limited irrigation coverage, high availability of annually replenishable groundwater, and high concentrations of marginalized farmers. Therefore, groundwater irrigation expansion in hard-rock areas could have dual benefits of ensuring future food security and targeting poverty reduction.