The river Ganga is primarily sustained by groundwater discharge, not glacial melt as widely believed, according to a study led by researchers at the Indian Institute of Technology (IIT) Roorkee. 

The study showed that natural underground contribution boosts the river’s volume by nearly 120 per cent along the middle stretch.

Meanwhile, more than 58 per cent of the river’s water is lost to evaporation during summer -- an alarming yet overlooked component of the river’s water budget.