Subsequently, the transport states in relation to the average flow velocity, shown in the figure, are explained further:

Transport state d), floating and sliding motion over deposits, does not have enough energy to transport all solid particles. The movement of the solids includes the bed load and suspended load, hence forming ripples, dunes and banks on the channel bottom. Deposit formation occurs because the average flow velocity in the channel cross section is substantially less than the critical flow rate. Eliminating deposit formation in large outflows requires velocities which are usually not reached during average rain events [Führb1979] [Führb62] [SteinR2005].