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To simulate all the irrigation phases and predict design parameters in borders, a zero inertia model was developed. The model is constructed on base of saint venant equations with no acceleration, inertia, terms. An implicit finite difference scheme was used to discrete the governing equations. This solution of the system of finite diffetence equations is obtained at each time step by iteration method. Two data sets due to Roth (1971) and Roth et al. (1974), and two other data sets which were obtained in the fields at agricultural research centers in Ahvaz and Karaj were used to verify the model predictions for advance and recession times, runoff volume, and volume of water inflltrated.Comparison of simulation results and field data obtained indicates that model predicts advance and rescssion times, and volume of water infiltrated very well but the runoff volume was underestimated.Also, predictions by the model were compared with results from hydrodynamic models of bassett (1973) and Strelkoff (1977). This comparison shows that the model is accurate. However, the computer code is simpler and less than existing hydrodynamic irrigation models and it also runs fast.