Ultimate bed slope in Calabrian streams upstream of check dams. Field study

In this paper a number of proposed criteria are analyzed that predict the ultimate equilibrium bed slope in streams upstream of a check dam. The analysis is based on a comprehensive data set that includes 132 reaches in streams located in southern Italy. The results of this study show that the procedures suggested by Ferro et al. and Julien and Wargadalam do not lead to satisfactory results. Better predictions of the ultimate bed slope are achieved using the criterion suggested by Gessler, which is based on the stochastic analysis of incipient motion in nonuniform bed material. This analysis is based on a design discharge corresponding to a return period of 1.2 years and accounts for the armoring process at the bed surface. The procedure allows an estimate of the equilibrium slope of a nonhomogeneous bed material.