Closed-end furrows are commonly used to irrigate crop in northern part of China. The irrigation performance of furrow in this area is often low. The objectives of this paper are to verify reliability of infiltration parameters and Manning roughness estimated with SIPAR_ID software and present an optimized method for design of closed-end furrow system. The study consisted of field experiments and numerical simulation. Field experiments were conducted in two villages of Yangling district in

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... r 2007. Infiltration parameters and Manning roughness values were estimated with SIPAR_ID software. The estimated values were put into the WinSRFR software, and then the advance trajectory, flow depths in the upstream, and irrigation performance were simulated on each test furrow. The results showed that the simulated values with the WinSRFR software were in excellent agreement with the measured data. Therefore, the infiltration parameters and Manning roughness estimated with SIPAR_ID software were reliable. Later, an optimized model for design of closed-end furrow irrigation system was proposed, based on field data and using the project of Uniform design and the WinSRFR software. Its solution required the use of optimized methodology with genetic algorithm (GA), and the inflow discharge and cutoff time were the independent variables. The results showed that adequate and efficient irrigations can be obtained using closed-end furrows through a proper selection of inflow discharge and cutoff time.