SYSTEM ANALYSIS OF AN IRRIGATION PROJECT

Abstract

Water, the most precious gift of the nature, is the prime natural resource and source of life. Development of nation depends upon the effective, efficient and appropriate uses of its water resources. Water, as a resource, is under relentless pressure due to population explosion with rise in living standard, rapid urbanization, large-scale industrialization and environmental demands. Therefore, it is necessary to develop, conserve, utilize and economically manage this critically important resource on an integrated basis so as to meet the ever- growing demand. Water resources planning and development is broadly concerned with the accurate assessment, identification and management of water from different sources for the welfare of the human being. In this work entitled "Systems Analysis of An Irrigation Project", an attempt has been made to assess the surface water potential of the Mula basin and to determine the optimal annual yields by simultaneously optimizing the cropping pattern for projects at the same time, satisfying the project specific demands to the maximum possible extent during a successful year. The virgin flow series at the Mula river basin have been generated using water balance equation to assess the annual gross water surface yield of the basin. Observed flows at Mula site, water utilization and its, regeneration, evaporation losses from the reservoirs, storage effects, import and 'export of water have been considered in the water balance equation. The total water demand includes the irrigation water demand, environmental demand. The irrigation water demand has been estimated using standard FAQ method and the environmental and ecological demand has been assessed as per the norms adopted by NWDA. The project proposes to irrigation area 80,000 Ha CCA, by varieties cropping pattern, the annual gross irrigation requirement to be 485.346 MCM and the annual gross surface water yield of the Mula river basin is estimated to be 627.03 MCM at 75 percent annual dependability. 111 System analysis techniques are widely used in the field of water resources planning and management. Linear Programming (LP) based models can handle a very large number of decision variables and constraints which are generally encountered during the studies on river basins. The integrated reservoir yield model, an implicit stochastic LP based model, is applied to assess the optimal annual multi-yields with specific reliabilities and to determine the optimal cropping plan of the projects. The result of integrated reservoir yield model (IRYM), the optimal active reservoir storage capacity is found to be 627.77 MCM for single annual yield target 627.03 MCM (i.e., irrigation demand as firm yield), at 75% annual dependability, i.e., 8 failure years. It is 100% to meeting the maximum annual irrigation target. ry