Reservoir Sedimentation

Book excerpt: Research on reservoir sedimentation in recent years has been aimed mainly at water resources projects in developing countries. These countries, especially in Africa, often have to cope with long droughts, flash floods and severe erosion problems. Large reservoir capacities are required to capture water provided by flash floods so as to ensure the supply of water in periods of drought. The problem arising however is that these floods, due to their tremendous stream power, carry enormous volumes of sediment which, due to the size of reservoirs, are virtually deposited in toto in the reservoir basin, leading to fast deterioration of a costly investment. Accurate forecasting of reservoir behaviour is therefore of the utmost importance.This book fills a gap in current literature by providing in one volume comprehensive coverage of techniques required to practically investigate the effects sediment deposition in reservoirs has on the viability of water resources projects. Current techniques for practically estimating sediment yield from catchments, estimating the volume of sediment expected to deposit in reservoirs, predicting sediment distribution and calculating scour downstream of reservoirs are evaluated and presented. The liberal use of diagrams and graphs to explain the various techniques enhances understanding and makes practical application simple. A major feature of the book is the application of stream power theory to explain the process of reservoir sedimentation and to develop four new methods for predicting sediment distribution in reservoirs.The book is primarily directed at practising engineers involved in the planning and design of water resources projects and at post-graduate students interested in this field of study.