Before revision: By itself, a live bed in a uniform channel will not cause a scour hole - for this to be created some additional increase in shear stress is needed, such as that caused by a contraction (natural or artificial, such as a bridge) or a local obstruction (e.g.
After revision: By itself, a live bed in a uniform channel will not cause a scour hole — for this to be created some additional increase in shear stress is needed, such as that caused by a contraction (natural or artificial, such as a bridge) or a local obstruction (e.g.