An analysis of the behaviour of fluid mud in estuaries

The movement of fluid mud has been cited as the most likely cause of rapid siltation in the majority of the ports in the world located in muddy estuaries. In the past, it has been very difficult to predict or quantify this extra siltation, which may in some cases double the annual maintenance dredging bill for a new port extension. A theoretical analysis was made of the behaviour of fluid mud in estuaries including a review of the literature. Basic theories were devised and modified to describe the formation of fluid mud from a more dilute suspension and its motion down a sloping bed and along a flat bed. The analysis casts a new light on several previously unexplained phenomena observed in estuaries.