Since time immemorial, Nepal, India and Bangladesh - three impoverished South Asian countries - have viewed the Ganga and its tributaries as perennial sources that sustain life.They warn that if nothing is done now by the governments and peoples of the region, the 'river of hope' could soon turn into the 'river of despair and gloom'."Fresh water in the region is not an infinite resource but a finite one," Mr Arifur Rehman, an adviser to Bangladesh's ministry of water resources said in Mumbai last week during an interaction programme organised by the Economic Development Institute of the World Bank attended by experts, journalists and academics from across the region.