Hairsine-Rose (HR) model is the only multi sediment size soil erosion
model. The HR model is modifed by considering the effects of sediment bedload and
bed elevation. A two step composite Liska-Wendroff scheme (LwLf4) which
designed for solving the Shallow Water Equations is employed for solving the
modifed Hairsine-Rose model. The numerical approximations of LwLf4 are
compared with an independent MOL solution to test its validation. They
are also compared against a steady state analytical solution and experiment
data. Buffer strip is an effective way to reduce sediment transportation for
certain region. Modifed HR model is employed for solving a particular buffer
strip problem. The numerical approximations of buffer strip are compared
with some experiment data which shows good matches.