An experience of forecasting unstable river channel changes (a case study of the Amu Darya upper reaches)

Abstract

A development of channel change forecasting is a task of great significance for natural river usage, for man-made changes of their regime and for gravity flowing channel construction. The problem is especially urgent in relation to rivers with unstable channel in erodible sediments. The paper describes a channel reach of the upper Amu Darya where time and rate of relief transformation appears to be an economic problem of great importance. Detailed channel studies carried out by Laboratory of soil erosion and channel processes (Moscow State university) have revealed main regularities of channel changes and factors they are conditioned with. The results have been used as a basis for channel changes forecasting and as a ground for complex of measures preventing unfavourable consequences of the changes.

High degree of the forecasting reliability allows to suggest a complex of studies which is necessary to carry out at rivers with unstable channel at the points of irrigation channel diversion, near bridges, ports etc.