  We consider the flows of Monsoon Rivers in India that will permit the river
to perform all its natural functions. About 80% of the total flow for Indian
rivers is during the monsoon and the remaining 20% is during the non monsoon
period. By carrying out a case study of the river Yamuna in Delhi we find that
at least 50% of the virgin monsoon (July to September) flow is required for the
transport of the full spectrum of soil particles in the river sediment. A
similar flow is needed for adequate recharge of the floodplain aquifers along
river. For the non monsoon period (October to June) about 60% of the virgin
flow is necessary to avoid the growth of still water algae and to support river
biodiversity.
