Abstract. One-dimensional (1D) flow models have been routinely used in practical hydraulic applications. Example models include HEC_RAS (Brunner, 2006), MIKE11 (DHI, 2002), CCHE1D (Wu and Vieira, 2002), and SRH_1D (Huang and Greimann, 2007). These 1D models will remain useful, particularly for applications with a long river reach (more than 50 km) or over a long time period (over a year). Their limitation, however, are well known and there are situations where multi-dimensional modeling is needed. For most river flows, water depth is shallow relative to width and vertical acceleration is negligible in comparison with gravity. So the two-dimensional (2D) depth-averaged model provides the next level of modeling accuracy for many practical open channel flows. Indeed, time has been ripe that 2D models may be routinely used for river projects on a personal computer. A range of 2D models have been developed and applied to a wide range of problems since the work of chow and Ben-Zvi (1973). The ability of a 2D model to solve open channel flows with complex geometries has always been a thrust for improvement as it is relevant to practical applications. In this report hydrodynamic and Sediment Transport Equations and Sensitivity Parameter Using the  Model are introduced.