Researchers from IIT, Bombay, have developed a model for deciding how much water should be released from multiple reservoirs into the river basin to curb wastage and, at the same time, prevent under-utilization. The current practice of releasing water from reservoirs is based on arbitrary planning which leads to under-utilization of water. Adopting the new model can help decide the duration and quantity of water to be released from multiple reservoirs.
The study is based on genetic algorithm or formula, which was successfully applied to the multiple reservoir system in the Upper Godavari basin comprising five reservoirs: Waghad, Karanjwan, Punegaon, Ozerkhed and Palkhed in Nashik. It indicated an 11% increase in benefits over the existing practice due to optimum supply of water to crops. Avinash .S. Garudkar, who is an external examiner for University of Punes, Bachelor of Engineering examination as well as the assistant professor at Water and Land Management Institute, Aurangabad, undertook the research along with A.K. Rastogi, and T. I. Eldho from IIT, Bombay, and S D Gorantiwar of Mahatma Phule Agricultural University, Rahuri.
The research, which has been recently published in Springer, a European research and development journal, focuses on optimum water release from reservoirs considering heterogeneity of the command area (such as different soil types and different crops). Optimum utilization of water means appropriate release for irrigation as per the requirement of different crops grown in different soils. The amount of water released should match the demand of water in the area under cultivation, said Garudkar. Releasing water for irrigation, hydropower, domestic use and industries from a single isolated reservoir is comparatively easy as guidelines for the same are available.
However, multi-reservoir operation in the river basin is complicated and has no guidelines on how much water should be released and when, also due to variations in the soil and crop types in the area under cultivation, he said. The present practice of water release from various reservoirs is based on arbitrary planning, influenced by the demand for water in the region, among other things. Moreover, different climatic conditions, and number of crops grown simultaneously in the command area with different soil types require different quantities of water, which further complicates the water release process.
Hence, the need for a mathematical tool to gauge the amount of water that should be released from different reservoirs so as to achieve maximum crop yield, added Garudkar. The new model decides the quantity of water that should be released from multiple reservoirs in the river basin, considering the heterogeneous requirements of the climate, type of crops and types of soil in the area of cultivation. The application of the model will enable all farmers in the command area to irrigate their land proportionally along with increasing their net benefits, added Garudkar.
The model uses the analogy of human genes and chromosomes for deciding water release from various reservoirs in the river basin to maximize benefits. Rastogi, who is a senior professor in IIT, Bombay, said, The earlier conventional optimization techniques offer inferior solutions to complex problems. Genetic algorithm, however, gives you the best solutions. These formulae or algorithms have also been used in other fields, such as for achieving structural optimization in architecture, groundwater optimization, or robotic movements and the like. Genetic algorithm gives you the best combination of resources, ensuring maximum benefits.
Courtesy: Times of India