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With an eye on all the natural functions of a river, the present article considers the flow of the river Yamuna in Delhi as an example of monsoon rivers in India. About 80% of the total virgin flow of Indian rivers is during the monsoon period and the remaining 20% is during the non-monsoon period. In case of the river Yamuna in Delhi, we find that at least 50% of the virgin monsoon (July to September) flow is required for 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 the river. For the non-monsoon period (October to June), at least 60% of the virgin flow is necessary to avoid growth of still-water algae and to support river biodiversity. We conclude that about 50–60% of the virgin flow is necessary throughout the year to maintain the health of the river system.

The book analyses the issue of river water sharing from various perspectives including hydrology, water treaties, disputes, different stakeholders in relation to inter-state water sharing and more. However, most laws and legislations were passed well before environmental issues were fully understood and the article presents issues and solutions that are environmentally sound.

This piece emphasizes the ecological importance of allowing rivers to flow their natural course, and the danger from interlinking these delicate evolutionary ecosystems