Potential groundwater recharge in north-western India vs spaceborne GRACE gravity anomaly based monsoonal groundwater storage change for evaluation of groundwater potential and sustainability

Abstract

The north-western part of India has been affected by severe ground water depletion. In this study, an attempt has been made to assess potential ground water recharge of North West (NW) India and its comparison with Gravity Recovery and Climate Experiment (GRACE) gravity anomaly based monsoonal groundwater storage change. An assessment of potential groundwater recharge was done in terms of terrain suitability for groundwater recharge and average monsoonal recharge. Terrain suitability was assessed based on hydrogeology and terrain parameters which were then integrated with the spatial variability in monsoonal recharge (expressed as the surface water column available for underground infiltration). The average monsoonal groundwater storage (GWS) change was derived from GRACE terrestrial water storage (TWS) change. An evaluation of potential groundwater recharge vs. terrain suitability for groundwater recharge and potential groundwater recharge vs. monsoonal GRACE GWS change shows that there is high terrain suitability but low potential groundwater recharge in the north-western part of NW India essentially due to very low precipitation. In the north-western part, terrain suitability is high primarily due to the presence of sandy alluvium, deeper sandy loam soil and flat terrain. The remaining alluvial plains, lithologically covered by unconsolidated sediments with loamy-silty-sand or clayey-loamy-silty-sand soils, show moderate terrain suitability. Rainfall induced surface water infiltration capacity is high in Upper Ganga drainage basin and in major parts of Narmada drainage basin but low to very low in Luni-Ghaggar drainage basin and in major parts of Yamuna and Chambal drainage basins. The average monsoonal GRACE GWS change is low in the north-western part of NW India which is in agreement with potential groundwater recharge scenario. The comparison between precipitation, terrain infiltration potential and GRACE gravity based average groundwater storage observations enables to evaluate prospective and vulnerable areas in terms of groundwater availability and sustainability in NW India.