Chapter 19 - Interlinking of Rivers as a Strategy to Mitigate Coeval Floods and Droughts: India in Focus With Perspectives on Coastal Zone Management

Abstract

India is the seventh-largest country in the world, covering an area of 3.29 millionkm2, which is only 2.4% of the world's land area, sustaining ~8% of the world's biodiversity. Owing to its unique geography, landscape, and rainfall pattern, the Indian subcontinent experiences dual problems related to water: severe droughts and flooding simultaneously in different parts of the country. In order to obviate this irony, linking glacier-monsoon fed perennial rivers of the north with seasonal rivers of the south has been proposed. On completion, the mammoth program of interlinking of rivers (ILR) will be the world's largest irrigation infrastructure project, linking 37 rivers through 30 links by establishing about 15,000km of new canals and 3000 dams of various sizes. Because each river basin acts as a holistic system in tune with the climatic, geological, and anthropogenic interactions, any study on the river system should understand the dynamics of the river basin as a whole. A river basin is a basic geographic and climatological unit within which the vagaries of natural processes act and manifest at different spatio-temporal scales. However, even if juxtaposed, no two river basins respond to natural processes in a similar way, and thus, each river basin is unique. Hence, any developmental activity or conservation effort has to be designed and implemented unique to each river basin. At this juncture, linking the diverse river systems that are distinct in terms of climate, geomorphology, geology, structure, land use, source of water, monsoon systems, biodiversity, human populace, and so forth as envisaged in the ILR stands unprecedented in terms of type, and magnitude. If so, the program poses severe constraints on the assessment of probable environmental, ecological, and other feedback, and strategizing remedial and reclamation measures. Recognizing this, we explore the interlinked nature of river systems and coastal stability, and probable impacts, and suggest necessary mitigation measures with reference to the proposed ILR. Preparation of natural environmental baseline data, based on which formulation of a masterplan within which subplans unique for each river basin and establishment of monitoring system on a short-medium-long term basis are suggested for effective implementation of the river linking and sustainable development.