India’s falling groundwater storage being replenished: Study

India’s groundwater storage, which had been falling steadily in recent years, is now being replenished according to researchers from IIT-Kharagpur and NASA. The dwindling supply of groundwater in India has been of great concern in recent years, with almost 60 per cent of the country being regarded as water stressed.

For the first time, researchers from India and abroad have given positive confirmation on the replenishment of groundwater storage at the regional scale. A research team from IIT-Kharagpur in collaboration with NASA scientists have reported replenishment of regional-scale groundwater storage (GWS) through long-term (1996-2014). The researchers used more than 19,000 groundwater observation locations, ground-based measurements and decadal-scale (2003-2014) satellite-based groundwater storage measurements.

“Our study shows a recent paradigm shift in Indian groundwater withdrawal, and management policies for sustainable water utilisation have probably started replenishing aquifers by increasing storage in western and southern India,” said research lead Abhijit Mukherjee from IIT-Kgp.

In parts of western (Gujarat) and southern (Andhra Pradesh) India, groundwater storage has been decreasing at the rate of -5.81±0.38 km3/year (1996-2001) and -0.92±0.12 km3/year (1996-2002) respectively. But this was reversed to replenish at the rate of 2.04±0.20 km3/year (2002-2014) and 0.76±0.08 km3/year (2003-2014), respectively. “We have been able to demonstrate the initial scenarios of rejuvenating groundwater in parts of India, which has the potential to be the largest groundwater replenishment occurrence in human history,” he added.