A VERY recent multiauthored paper titled ‘Mapping the world’s free-flowing rivers’ has been published in the journal Nature.
The notion of free-flowing rivers became popular in the Western world, especially with the initiatives of the World Wide Fund for Nature (WWF). The working definition of a free-flowing river goes as a river system that is largely unaffected by human interventions in its flow and connectivity. This entails a flow regime with water, silt, and other natural materials sustaining the basin ecosystem in its natural form. WWF network puts this as a system where “… river dolphins and migratory fish, can swim up and down stream at will. And the river itself can swell and shrink naturally, flow at an organic volume and rate, and replenish groundwater sources.”.
This idea resonates well with the WaterEnergy-Biodiversity-Sediment (WEBS) concept articulated by renowned river expert Jayanta Bandyopadhyay. WEBS is an important step towards developing a holistic basin governance perspective that includes combining the social and cultural aspects with ecological and engineering perspectives. The basin is looked at as a complex combination of water, energy, biodiversity, and sediment through the inextricable linkages with ecosystems and livelihoods.
Human interventions on hydrological flows for energy (hydropower projects) inhibit the river’s capacity to carry sediments downstream for soil formation of the deltaic regions. It also arrests movements of aquatic species, often affecting their breeding behaviours, and food habits, causing their extinction.
So, a free-flowing river entails keeping water instream to preserve its immense ecosystem functions, and the ecosystem services, for the human community. This kind of water management — favouring demand management and ecosystem restoration is in consonance with integrated basin governance. However, Indian water policymaking is dominated by the reductionist, structuralist engineering paradigm looking at short-term economic benefits, and ignoring longterm sustainability concerns.
This owes its origin to the establishment of Thompson Engineering College at Roorkee (now IIT Roorkee) during the British era that provided young Indian students with training in the European knowledge of water engineering. Early British projects had been exemplified by the Sarada Barrage, flood control of the Kosi, and the Upper Ganges Canal to divert water from the Ganga at Hardwar near Roorkee.
The European engineering paradigm would not have much idea of Indian rivers, as it hardly had a concept of ‘drought’ (or lean season flow) and ‘floods’ (peak flow) in ‘arithmetic hydrology’, where abundance or scarcity is defined only in per capita terms. Most European rivers hardly revealed any seasonal pattern. So, regular annual occurrences of monsoon floods in the Ganga or the Cauvery floodplains were considered aberrations.
Even sediments were treated as a problem, rather than an ecosystem service, as British engineers hardly documented sediment in the planning and conceptualisation stage. So, in the Bihar floodplain in the Ganga sub-basin of India, what was apparently perceived as ‘flood damage,’ was actually a process of sediment deposition that leaves behind rich silt and micronutrients that have helped in the natural creation of the ‘rice bowl’ of South Asia. Further downstream, the Farakka Barrage, constructed in 1975 to resuscitate the Calcutta port, resulted not only in stream-flow depletion in its natural course, but also sediment deposit in its upstream that has often been termed to be the cause behind upstream Bihar floods. This is due to the ‘backwater effects’ when high flows in the Ganga and its left-bank tributary, Koshi, coincide.
On the other hand, the sediment carrying capacity of the mainstream Ganga has reduced substantially thereby inhibiting the soil formation of the Bengal delta.
The reductionist tradition of ‘arithmetic hydrology’ is extremely prevalent with the way government machineries define ‘environmental flows,’ whose globally accepted definition is “the quantity, timing, and quality of water flows required to sustain ... ecosystems and the human livelihoods ...that depend on these ecosystems.” In contrast, the entire needs for the ecosystem have been reduced to a single number expressed as percentage of the total flow by the ministry of water resources, river development and Ganga rejuvenation on the basis of some arbitrary methods proposed by IIT Kanpur.
Similarly, the suicidal idea of interlinking of rivers is based on the unsubstantiated premise of ‘scarce’ and ‘surplus’ basin definition, resulting from this reductionist engineering thinking which fails to recognise that every drop of water has an ecological function. Before the just-concluded election, the newlyelected party at the Centre had written in its manifesto that all issues related to water will be brought under one umbrella body. If implemented, this will be a step towards holism out of the existing fragmentation. However, institutional holism is not sufficient; it has to exist in approach and practice. At a basin scale, the idea of ‘free-flowing rivers’ needs to be adopted by the new body, if formed, to the extent possible. A secure hydrological future requires keeping water instream through demand management.
This commentary originally appeared in Mail Today.
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Dr. Nilanjan Ghosh is a Director at the Observer Research Foundation (ORF), India. In that capacity, he heads two centres at the Foundation, namely, the ...
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