Optimizing Water Distribution in Irrigation Canals Using the NSGA-II Algorithm

Abstract

【Objective】 Optimization of water distribution in irrigation districts is a way to improve water use efficiency and water resource management. This paper proposes a method to optimize water distribution in irrigation canals. 【Method】 The flow rate in the canals at the lower end and the number of rotational groups are taken as the decision variables. The objectives of the optimization are to minimize the total water distribution duration, the distance between the upstream and downstream canals in the same group, and the difference in water distribution duration in each canal in the same rotational group. The optimization considers the constraints of time, outlet state, canal overflow capacity, and water balance. The model is applied to the Shipi East branch canal in Bojili irrigation regions, and the optimization is solved using the NSGA-II algorithm by dividing the lower-end canals into nine rotation irrigation groups. 【Result】 Dividing the adjacent canals into one round grouting group as possible as it could, and opening and closing them simultaneously to facilitate the management, the water distribution flow rate and total water distribution time calculated by the model meet the operational requirements. 【Conclusion】 The optimization model proposed in this paper can distribute water between canals to achieve high flow rate, short duration and less workload. It can be used to help improve water management in irrigation districts.

Keywords

• multi-objective water distribution
• canals water distribution
• rotational irrigation
• optimization model