OPERATIONAL GUIDANCE FOR REDUCING CONVEYANCE LOSSES IN CANALS WITH RESPECT TO DEMAND VARIATIONS

摘要

One of the major reasons of water wastage in irrigation canals are the operational losses a complex function of unsteady behaviour of flow that should be controlled. Demand variation in irrigation canals is associated with the operation of structures and flow regulation. Any regulation or structure adjustment in response to demand variation causes unsteady flow in canals. In this research, ICSS hydrodynamic model is used to analyze unsteady flow in response to demand variation of E1R1 canal of Dez irrigation network with 6 turnouts and appropriate operation instruction is determined. For this study, 20% increase of water delivery for the two most downstream turnouts is considered and 3 scenarios for opening or closure of 4 upstream turnouts are taken in to account. These scenarios simulated under nonoperation conditions and 6 hours water delivery in order to quantify operation losses. According to the results of simulation, proper operation instruction is determined. Volume of water loss in both operation and nonoperation situation are calculated and the impact of proper operation on improvement of operation efficiency is determined. The maximum water saved due to appropriate operation instruction is about 3971 cubic meter.