averaging, but we have found that the approach given by Equation (24) gives the most consistent
results under a wide variety of grid configurations. We note that under certain grid configurations
it was observed that mild in-plane (x-y plane) oscillations appeared in the continuous
representation of the bed. The weighted angle approach minimized the appearance of these
oscillations, which were often much more visible using other averaging techniques. It should be
noted this procedure does not affect the local conservation property of the sediment due to the
fact that z is not actually used in the computations for updating the bed.