ABSTRACT
What is scour? According to an Internet notice: ‘Scour is the removal of sediment (soil and rock) from streambeds and streambanks caused by moving water. Although scour may occur at any time, it is usually more significant during high flows, when the water is swift and deep. Swiftly moving water has more energy to lift and transport sediment than slowly moving water’. Is this really correct? We do not think so because an important point related to scour is the local erosion of sediments. Sediment transport, in contrast is more extended where sediment is dislocated and possibly deposited again. The difference between (more gradual) erosion and (concentrated local) scour of sediment in fluvial hydraulics may be the principal reason for complication with scour descriptions.
