ENVIRONMENTAL MITIGATION OF SEDIMENT ACCUMULATIONS AT DRINKING WATER STATIONS INTAKE IN EGYPT

Abstract

The construction of the Aswan High Dam (AHD) and a storage reservoir on the River Nile caused an imbalance of sediment discharges downstream of the dam. The river between Aswan and delta barrages is divided into four reaches by a series of barrages (Isna, Nag Hammadi, Assuit and delta). The regime of sediment transport was changed significantly in the reaches upstream of the barrages. Excessive sedimentation at water intakes on rivers causes interruption in water supply and may damage of pumps with consequent high operating costs. The problems of sedimentation at drinking water station intakes on rivers could be minimized by applying a new technique that can be added within the components of drinking water station intakes. Sedimentation problems are relatively common along the River Nile. The water intakes located on the River Nile had experienced chronic problems with bed sediment buildup. The sediment, comprising a mix of silt and sand, hindered the operation of the intake’s pumps. Partial blockage by sediment restricts water flow through the system’s tubes, elevating turbine backpressure, and reduces the station’s efficiency. it is required to remove sediment accumulated within the intake, and dredge the river bed in the vicinity of the intake periodically. at the water intakes located along the River Nile' banks which are prone to sedimentation problems, there is a need to remove sediment from the intakes to ensure continuous water supply from these intakes, and to protect the pumps against damage and sediment clogging. This research studies the environmental impact as a result of accumulated sediment in front of water intakes, because of the dredging V process in front of these stations. For example, this can be affected on the flora, fauna, river navigation, fisheries, and water quality. The study aims to find a technical solution suitable for using to reduce the negative impact of sediment problem in front of water intakes on River Nile, in order to improve operating efficiency. So the suggested new technology can be added within the components of water intakes that suffer from the sediment problem to overcome this problem. Thesis components: This study includes seven chapters as follow: Chapter (1): (Introduction) This chapter introduces the main items of this research and gives a general idea about it. The main target of this research is to mitigate the contaminated sediment at front of water intakes along River Nile. Furthermore, this chapter explains the main objectives of the research and study plan and research components. Chapter (2): (Literature Review)