ABSTRACT
An understanding of the behaviour of river beds and banks is important to the designer of any river structure. The process of scouring in rivers can result from natural phenomena or from man-made alterations; either of these can produce effects over long reaches of the river or only locally. General scour occurs because of the increased capacity of a river to carry sediment during flood flows or as the consequence of various man-made alterations. In order to reduce the construction cost of bridges, the cross section at a crossing is often reduced by encroachment of the embankments on the flood plain or even on the river channel. The importance of meandering is that meander patterns propagate slowly downstream. It cannot be overemphasized that in order to comprehend the likely tendencies of the river to change its shape and location, the designer must collect and study a variety of relevant information including particularly the experience with former constructions in comparable conditions.
