الفهرس 
CHAPTER (1) INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
River transport is one of the oldest and most economic means of transport in the world. Dredging is currently used as a temporary work to keep the navigable. Also, most the intake places of water plants and power along the river are dredging to keep their efficiency. Due to the lack of an integrated management of the ongoing and the study of the impact on the river morphology and forecasting variables incident dredging operations. Hence, the dredging processes repeated annually at different locations cause direct disturbance in the river, consequently leads to many changes in the behavior of the Nile. The re-dredge process was also found to increase the annual cost of maintenance at such locations. Accordingly, this research aims to analyze and evaluate the effect of re-dredging at navigational bottlenecks and the intakes of water plants and power on the river morphology. In addition, it would be predicted the rate of the morphological changes (general degradation and aggradation) expected along the River Nile navigational path using available records of historical and recent data and by applying the mathematical model. The results could support decision-makers to plan integration measures to limit the complications of re-dredging on the river stability. For achieving this goal, Korimat region that lies between km 86 to km 99 U/S Roda are selected. The study reach had been subjected to much re-dredging work at several navigational bottlenecks and also around the intakes of Korimat water plant
and power. A comprehensive field survey for data collection was conducted.
Many set of aerial hydrographical survey maps during the period 1982, 2005, 2012
and 2016 were mainly prepared by digitized maps, computer programs consequently studied, analyzed and evaluated the study area characteristics with the time. A 2-D model (Delft3D) was used for the simulation and prediction purposes. The calibration and verification were performed by the model using available data for years 2004 and 2005 respectively. Then, it was applied the critical proposed scenarios.
The output results were reviewed evaluated and analyzed. They included the resulting changes in the bed morphology along the study area and determine some critical situations were shown within the study region that directly affected the efficiency of the navigational path.
Four scenarios were applied using the recent hydrographical data at year 2016 to simulate the dredging operation scenarios in case of releasing the proposed discharges which the maximum and minimum discharge within the period 1982 to 2009 years.
Consequently, it may help the decision makers to take actions to improve the
integrated dredging management system.
The first scenario represent in the natural case without any dredging for the navigational path or around the intakes for evaluating the natural morphological changes without any human intervention. While the second scenario was applied in case of dredging, the current navigational path at the west channel of Korimat Island and the dredging in front of the water and power stations, which locate at the east channel to analyze and evaluate their efficiency. The third scenario aimed to suggest alternative navigational path in the east channel as the same path at year 1982 to manage the dredging processes and to redistribute the flow in the east and west channel around the Korimat island. The fourth scenario applied to show the effect of applying the closure dam with three different trials for its dimension. This scenario is useful to redirect at most of flow to the east channel to improve the efficiency for both
the navigational path and the water and power station. On the other hand, it has some of side effects on the river morphology. from the analysis and evaluation the model results, the third scenario is considered the optimum solution according to manage the
dredging processes. In addition, the rate of deposition in the front of the water and power intakes and navigation bottlenecks would be decreased consequently the efficiency for their increase. Moreover, the island will not attach with any side of banks therefore it helps the Korimat island keeps its characteristic.