Canal water distribution optimization model based on water supply conditions

Abstract

The optimization of canal water distribution is vital in irrigation areas because a reasonable distribution is required to improve the water distribution efficiency and maximize the benefits of water resources. In this paper, under the condition that the total volume and flow rate of water supply in the primary canal have been determined, the water supply is compared with crop water demand, and three optimal models of canal water distribution are established. In situation 1, the total volume of water supply is sufficient to meet the crop water demand during the growing period. In situation 2, the water supply is insufficient to meet crop water demand during their growth period; however, this problem is resolved by extending the water supply period. In situation 3, the water supply cannot meet the crop water demands during the growth period, even after adjusting the water supply period. Because the proposed water distribution optimization model is based on water supply conditions in irrigation areas, the irrigation area managers can easily develop their operation water distribution schemes. The model was validated using the Bojili irrigation area. Results showed that the model’s calculated variation trend of the main-canal flow rate was similar to the actual flow rate, and irrigation area managers could meet the model requirements with a small adjustment in the actual flow rate. The model also considered canal leakage loss, timely water distribution, water distribution fairness, and other goals, potentially improving agricultural water efficiency and water distribution satisfaction as well as promoting sustainable agricultural development. The model presented here is universal and can be used in other irrigation areas.