The accuracy of numerical models' was checked by comparing the designed and gated discharges with the models values. For designed flow discharge in the old stilling basin, the numerical model produced 440.5 m³/s discharge that underestimated only 0.79% discharge compared to the designed value of 444 m³/s. However, in the new stilling basin, this error increased up to 0.89%, that produced 440 m³/s discharge. For gated flow in the old stilling basin, the model produced 0.32% higher discharge compared to orifice discharge of 44 m³/s. However, in the new stilling basin, the model underestimated the discharge up to 1.2%. These validation results indicated that the present numerical models using FLOW-3D have produced acceptable results, and allowed for further analysis of hydraulic jump characteristics in the stilling basins under study. The results of different characteristics of hydraulic jump in the two stilling basins are presented in Table 4.