The impact of a dam-break wave on an erodible embankment with a steep slope has been studied recently using both experimental and numerical approaches. In this paper, the semi-implicit staggered scheme for approximating the Shallow Water Equation - Exner model will be elaborated to describe the erodible embankment (in the form of sediment) on a steep slope. This scheme is known as a robust scheme to approximate shallow water-Exner model. The results are shown in a good agreement with the experimental data. The comparisons of numerical results with data experiment using slopes \Phi=59.04^o and \Phi=41.42^o by coefficient of Grass formula Ag=2 \times 10^-5 and Ag=10^-5 respectively are found the closest results to the experiment. This paper can be seen as the additional validation of semi-implicit staggered scheme in the paper of Gunawan, et al (2015).