Abstract. Groundwater recharge sustains groundwater discharge, including natural discharge through springs and base flow 15 to surface water as well as anthropogenic discharge through pumping wells. Here, for the first time, we compute long-term (1996)(1997)(1998)(1999)(2000)(2001)(2002)(2003)(2004)(2005)(2006)(2007)(2008)(2009)(2010)(2011)(2012)(2013)(2014)(2015) groundwater recharge rates using data retrieved from several groundwater level monitoring locations across India (3.3 million km 2 area), the most groundwater-stressed region globally. Spatial variations in groundwater recharge rates (basin-wide mean: 17 to 960 mm/yr) were estimated in the 22 major river basins across India. The extensive plains of the Indus-Ganges-Brahmaputra (IGB) river basins are subjected to prevalence of comparatively higher recharge. This is mainly 20 attributed to occurrence of coarse sediments, higher rainfall, and intensive irrigation-linked groundwater abstraction inducing recharge by increasing available groundwater storage and return flows. Lower recharge rates (<200 mm/yr) in most of the central and southern study areas occur in cratonic, crystalline fractured aquifers. Estimated recharge rates have been compared favorably with field-scale recharge estimates (n= 52) based on tracer (tritium) injection tests. Results show precipitation rates are not significantly influencing groundwater recharge in most of the river basins across India, indicating 25 human influence in prevailing recharge rates. The spatial variability in recharge rates could provide critical input to policy makers to develop more sustainable groundwater management in India.

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