Water distribution and scheduling model of an irrigation canal system

Abstract

A complete water distribution scheme should include the scheduling of the check gates and turn out gates. This study aims to resolve the water distribution problem in irrigation districts based on channel hydrodynamic simulation and using the hydraulic factor of water level increase in backwater areas. The supply-decided water distribution and scheduling model(SD-WDSM), the demand-decided water distribution and scheduling model(dd-WDSM) were established respectively. The model was applied to the Bojili irrigation district to verify it’s applicability. The results show that the SD-WDSM can adjust the length of the backwater area through the operation of the check gate, ensuring a large flow rate at the turn out gate. The dd-WDSM was established to group the water diversion canals by rotation irrigation, and the turn out gate in the same group could open and close simultaneously, which is convenient for the administrator to operate. The two models also ensure that the water is diverted as early as possible, and the operation numbers of the check gates and the turn out gates are less. The model obtains the complete scheduling scheme of the check gates and the turn out gates in the water distribution system. This model can improve agricultural water use efficiency and promote sustainable agricultural development. The proposed model is universal and can be applied to other irrigation districts.