Nile Basin Capacity Building Network 'NBCBN' River Morphology
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Nile Basin Capacity Building Network ‘NBCBN’ River Morphology Research Cluster GROUP III WATERSHED EROSION AND SEDIMENT TRANSPORT Survey of Literature and Data Inventory in Watershed Erosion and Sediments Transport BY Mr. Longin Ndorimana Mr. Astere Nindamutsa Dr. Samy Abdel-Fattah Saad Dr. Bayou Chane Dr. Ahmed Khalid Eldaw Dr. Hassan Fadul Dr. Osman Mohammed Naggar Coordinated By: Dr. Kamaleldin Bashar, Scientific Advisor: Prof. G. J. Klaassen, UNESCO-IHE 2005 NBCBN / River morphology Research Cluster EXCUTIVE SUMMARY Many parts of the Nile Basin are witnessing soil degradation and loss associated with erosion resulting from over exploitation of forests and vegetation cover. This is particularly severe in the Ethiopian highlands as well as in the Equatorial region. The arid and semi-arid regions of the basin are now experiencing serious environmental degradation and spread of desertification. Research is needed in watershed erosion and sediment transport to deal with problems such as: (1) increase of losses in soil & water; (2) increase of sediment deposition in reservoirs; (3) increase of sediment entering irrigation canals; (4) prediction in changes in river morphology; (5) evaluation of practical methods to conserve soil and water; (6) minimizing sediment transported by irrigation canals (7) appropriate sediment measuring techniques; (8) deterioration of quality of water. The overall aim of this research area is to provide Capacity Building in Watershed Erosion and Sediment Transport, in the Nile Basin Countries involved, to sustainably manage the water resources of the Basin. Considering the boundary conditions imposed by the time limit and budget constraints, the first phase proposed for this research was a survey of the literature and data inventory in water shed erosion and sediment transport. The objectives of this research proposal are: 1/ review and synthesize available data [their sources, availability, extend and quality); 2/ identification of gaps and/or new data needed and 3/ elaborate appropriate regional database network. Four countries are involved, viz: Burundi, Egypt, Ethiopia, and Sudan. Sudan will be the regional coordinator. It has been agreed on a number of activities as shown by the following matrix (L being the Lead Country and M Being the Member Country): Activity Matrix Activity Burundi Egypt Ethiopia Sudan Surveying the Literature in Sediment Yield M M L Surveying the Literature in Soil Conservation M M L M Measures Inventory of Sediment Transport Data M M M L Collection of Studies in Sediment Transport M M M L Inventory of Data on Sediment Load M M M L (including reservoir data) Comparison of Measuring Techniques M L M M Preparation of Report M M M L Results Phase ( 1) During Phase 1 the activities have concentrated on a survey of the literature and data inventory on both watershed erosion and sediment transport in the Nile basin. • Review and synthesize available data [their sources, availability, extend and quality); Watershed Erosion and Sediment Transport i NBCBN / River morphology Research Cluster • Identification of gaps in knowledge and data available and/or identify need for additional data collection • Elaborate appropriate regional database network. • Description of measuring methods and techniques for sediment transport in rivers which has resulted in the following products to be included in the Phase 1 report: • Survey of the literature on sediment yield • Survey of the literature in soil conservation measures • Inventory of sediment transport data • Collection of studies in sediment transport • Inventory of data on sediment load (including reservoir data) • Comparison of sediment measuring techniques Future Research Plans • Setting up and preparation of data base(s) on sediment yield and sediment transport in the Nile basin • Assessment of sediment yield in selected areas using remote sensing and GIS • Estimation of sediment from sand encroachment and gully erosion • Proposing more improved sediment transport measurement techniques • Cooperation with other activities like FRIEND/NILE is considered, in particular for the data base part. Watershed Erosion and Sediment Transport ii NBCBN / River morphology Research Cluster TABLE OF CONTENTS 1 INTRODUCTION.......................................................................................................................... 1 1.1 Background............................................................................................................................ 1 1.2 Why need for research in Watershed Erosion and Sediment Transport?............................... 2 1.2.1 Increase of Losses in Soil & Water............................................................................... 2 1.2.2 Increase of Sediment Deposition in Reservoirs ............................................................ 2 1.2.3 Increasing of Sediment Entering Irrigation Canals ....................................................... 2 1.2.4 Prediction of River Morphology ................................................................................... 2 1.2.5 Evaluation of Practical Methods to Conserve Soil and Water ...................................... 3 1.2.6 Minimizing Sediment Transported by Irrigation Canals............................................... 3 1.2.7 Appropriate Sediment Measuring Techniques.............................................................. 3 1.2.8 Deterioration of Quality of Water ................................................................................. 3 1.3 Research Objectives............................................................................................................... 3 1.4 Work Group........................................................................................................................... 4 1.5 Work Plan.............................................................................................................................. 5 1.5.1 Activities and Role of Member Countries..................................................................... 5 1.5.2 Activity Matrix.............................................................................................................. 5 1.5.3 Surveying the Literature in Sediment Yield.................................................................. 5 1.5.4 Surveying the Literature in Soil Conservation Measures.............................................. 5 1.5.5 Inventory of Sediment Transport Data.......................................................................... 6 1.5.6 Collection of Studies in Sediment Transport ................................................................ 6 1.5.7 Inventory of Data on Sediment Load (including Reservoir Data) ................................ 6 1.5.8 Comparison of Measuring Techniques.......................................................................... 6 1.5.9 Carrying Special Type of Sediment Transport.............................................................. 7 1.5.10 Preparation of the Report .............................................................................................. 8 1.6 Output .................................................................................................................................... 9 2 LITERATUR REVIEW............................................................................................................... 10 2.1 SURVEYING THE LITERATURE IN SOIL CONSERVATION MEASURES............... 10 2.1.1 Introduction................................................................................................................. 10 2.1.2 Soil Erosion................................................................................................................. 10 2.1.3 What is Conservation? ................................................................................................ 10 2.1.4 Causes of Soil Erosion ................................................................................................ 10 2.1.5 Soil and Water Conservation in Selected Countries in the Nile Basin: ...................... 12 2.1.6 Soil and climate types ................................................................................................. 17 2.1.7 Types of erosion.......................................................................................................... 18 2.1.8 Measuring of Soil Erosion........................................................................................... 18 2.1.9 Erosion Control Measures........................................................................................... 19 2.1.10 Run-Off Control Measures for Soil Conservation ...................................................... 20 2.1.11 River (or stream) bank erosion control........................................................................ 22 2.1.12 Maintenance ................................................................................................................ 25 2.2 SURVEYING THE LITERATURE IN SEDIMENT TRANSPORT ................................. 25 2.2.1 Introduction................................................................................................................. 25 2.2.2 Bed Load Transport Rate ............................................................................................ 26 2.2.3 Suspended Load Transport Rates................................................................................ 26 2.2.4 Total Load Transport Rates........................................................................................