5-Decision Making for Conjuctive Water Use Planning in Inter-Basin Transfer Framework.

Abstract

The Inter-Basin Water Transfer (IBWT) as conceived in inter-linking of rivers is aimed at promoting integration of water resources through a national water grid on the concept of surplus and deficit basins for economic prosperity as well as socio-economic development from the national viewpoint. The present study examines the role of decision making in various issues of IBWT, categorized under conceptual framework, environmental, social and conjunctive water use plans. The study reveals that the main crux of the inter-basin transfer does not lie in identifying the surplus and deficit basins, but in quantifying the amount by which these basins will have surplus or deficit water. The need of conjunctive use of surface water and groundwater in the IBWT is explored and emphasized, and models dealing with and without water quality restrictions/scenarios are presented and discussed. Intervention to the natural hydrologic system with the gigantic order is bound to give sizeable adverse implications, which may be hydrological, environmental, social, economic as well as operational on short-term as well as long-term basis, and thus there is a need to have a holistic approach to visualize the interlinkages of various components of hydrological regimes and their interactions with ecosystems so that potential adverse consequences can be diagnosed and evaluated accurately. Muhicriterion approaches to deal with Multiobjective Decision Problems such as adhoc preference function programming, PORTRADE, E-constraint, weighting and surrogate worth tradeoff methods are also discussed to deal with non-commensurate divergent outcomes resulting from various viewpoints of IBWT to yield meaningfid, feasible, viable and implementalble solutions that can help greatly in decision making of inter-basin water transfers. It enables in collating and analyzing tangible and intangible outputs obtained from various implications and conjunctive water use studies to address pertinent issues associated with the IBWT, to perfOrm tradeoff analysis and to account for uncertainties associated with hydrological variables and vagueness associated with environmental and social objectives. The approach and models presented can provide an effective Decision Support System in chalking out best policies for t he ii ntegrated development and management of water resources i n t he I BWT framework to fulfill the desired economic and social development objectives while ensuring the sustainability of surface water as well as groundwater resources and restricting the damages to ecosystem and hydrosystem below the acceptable threshold limits.