Abstarct
A two-dimensional hydraulic flow model was developed using the SMS software (Surface Water Modeling System) to simulate the flow properties(thalweg line location) for meander in trapezoidal section channel, and its changes when a single emerge spur dike install at mid of the bend. The model was calibrated and verified through matching velocity profiles throughout the study reach. Thalweg line location were found due to the variation of spur dike characteristic including 180 runs, included five different ratios of spur dike length to top channel width (L/Tw), five ratios of spur dike arm to its body length (l/L), and two spur arm`s direction for four different flow rates, as a result, through the flow configuration the new location of the thalweg in the bend channel after using the spur dike was about (44-71)%Tw which mainly affected by spur body length.
