Deanship of Scientific Research, University of Gezira
Abstract
The development in Sudan is basically dependent on the Blue Nile water. The high sediment load brought by the river during its flood has major influences on the design and operation of the reservoirs built across the river and the schemes irrigated from it. Sediment deposited in reservoirs reduces the useful life of the reservoirs as well as diminishes the benefits from the dam (irrigation and power genera(ion). Large operational costs are incurred every year in dredging the sediment from reservoirs and canal sediment clearance. The sediment monitoring programme launched in 1988 in Gezira Scheme and the Blue Nile, has revealed very important results and answered many vital questions regarding sedimentation in Gezira Scheme. On average 8.5 million tons of sediment enters Gezira scheme every year. More than 97% of this sediment is very fine; therefore, standard methods of sediment exclusion at the intakes will not offer a solution. More than 70% of the sediment can be excluded if the canals gates are closed during the period 20th July to 31st August.
This paper reviews the sedimentation problem in the Blue Nile and Gezira Scheme and its management options based on the outcomes of the monitoring programme
