This paper summarizes an experimental study of debris now which originates from the progressive erosion caused by water discharge on a steep, saturated slope. The initial slope was built with a horizontal rigid bottom and was composed by grains of either uniform diameter (respectively 2, 7 and 22 mm) or by a mixture of grains of these diameters. The resulting mixture was in the so-called "grain inertial range". Different characteristics of the debris now were investigated, with special attention to volumetric solid concentration and liquid-phase pressure. Experimental results are discussed and compared with experimental findings of other authors.
