Estimating the flash flood quantitative parameters affecting the oil-fields infrastructures in Ras Sudr, Sinai, Egypt, during the January 2010 event

This paper aims to quantify the hydrological parameters for the flash flood event of 17th January 2010 in Sinai using multiple sets of remote sensing data and field work for the nongaged catchments (approximately 2100 sq km) of the wadis affecting Ras Sudr area, which is heavily occupied by numerous oil fields and related activities. The affected areas were visited, and several cross sections of the main active channels were surveyed to estimate the peak discharge rates. The Tropical Rainfall Monitoring Mission (TRMM) data have been used to estimate rainfall parameters for the catchments due to the absence of in situ data. The digital elevation model (DEM) of the Shuttle Radar Topography Mission (SRTM) was used to extract the hydrographic data following standard procedures and techniques of the Geographic Information Systems (GIS). Both of the surveyed and extracted parameters for the active channels were integrated into GIS to estimate the runoff parameters using the open-channel flow equation of Manning’s. The simulated hydrographs show that the total discharge exceeded 5.7 million cubic meters and the peak discharge rate was 70 cubic meters per second. The mitigation of extreme flash flood is possible by altering the natural flow dispersion over the alluvial fan, and conveying the resulting flows into one adjusted channel

Assessment of hydrological changes in the Nile River due to the construction of Renaissance Dam in Ethiopia

This paper assesses impact of the Renaissance Dam on Ethiopia; on the Nile discharge ultimately reaches Egypt downstream. The Landsat-8 satellite images of 2013 were obtained and interpreted to identify locations for the construction sites for the Renaissance Dam. Then the Shuttle Radar Topography Mission (SRTM) data were obtained and processed to create a digital elevation model (DEM) for the Blue Nile upstream areas that will be submerged. Different scenarios for the dams’ heights and resulting storages were simulated to estimate the resulting abstraction of the Blue Nile flows until completion of the project and the annual losses due to evaporation thereafter. The current site (506 m asl) for the Renaissance Dam allows the creation of a 100 m deep reservoir with a total storage of 17.5 km3; overflows will occur at that lake’s level (606 m asl) from the north western part of the developed lake into Rosaires downstream. Construction of the spillway dam to control the overflow area can allow the creation of a 180 m deep lake that store up to 173 km3 in a lake that will cover 3130 km2. The analysis of Tropical Rainfall Monitoring Mission (TRMM) suggests that the variation of total annual rainfall could reach 20%, thus the resulting hydrological fluctuations could affect the estimated filling time, the operational functions and discharge downstream. The negative hydrological impacts of the Renaissance Dam will increase by increasing the height of its spillway dam, as increasing the storage capacity could affect the strategic storage for the reservoirs in Egypt and Sudan. It is strongly recommended that an agreement should be reached to compromise the storage capacities and water supplies for all dams on the Nile to thoroughly satisfy the necessary needs

Management of waste water discharge within the Nile Valley of Egypt: The collapse of Al Ballanah waste water’s lake in Aswan in September 2013

This paper investigates the management strategies of waste water being conveyed into the hinterland of the Nile Valley areas in south Egypt. The inappropriate planning for sanitation drainage and treatment localities and consequent waste water use has developed an environmental disaster. The surplus accumulation of waste water into the evaporation lake led to its collapse in September 2013, and the flows contaminated the agricultural areas and the Nile River. Remote sensing data, digital elevation models (DEM) and soil maps were integrated into geographic information system (GIS) to ensure the full consumption of waste water via evaporation and cultivation of appropriate non-edible crops. The annual produced treated-water is approximately 10 million cubic meters, and the existing cultivated woodland covers 140 ha, which only consumes 1.1 million cubic meters of water. The oxidation and evaporation lakes and ponds annually consume 4 million cubic meters. The available soil suitable for reclamation is distributed within higher topography areas that require pumping via pressure lines. These soils cover 554.6 h and would consume up to 10.5 million cubic meters, which is sufficient to consume the treated water. Given the current difficulties to cultivate the available soil, the surplus accumulation of waste water can further be consumed via increasing evaporation rates from the water bodies through the introduction of voracious water crops such as water hyacinth. Additionally, these water plants will enhance the quality of waste water and could be used as raw materials for other purposes. Keywords: Remote sensing, GIS, Environment, Nile, Waste water, Cultivatio

The Implications of the Topographic, Hydrologic and Tectonic Settings Onthe Development of Bahr El-Ghazal Catchment, South Sudan

Abstract: Bahr El-Ghazal is considered to be one of the most unique catchments within the Nile Basin. It receives ~1280 mm of rainfall that produces ~21.4 billion m of water every years, only 0.5 billion m reaches 3 3 Lake No at the upstream of the White Nile.All the remaining water budget of this catchment is being consumed in theswampsregionat the lower part of the catchment, where the inflows are almost entirely lost to both evaporation and subsurface percolation. This is why the water budget of Bahr El-Ghazal catchment is considered negligible when calculating the waterresources for the downstream arid countries (Sudan and Egypt). Recent studies indicated that certain parts of the catchment are probably active. Observations from high-resolution satellite imagery indicate that there is a progressive flow-direction change in some tributaries, with the most recent ones flowing towards the swamps areas, suggestingthe presence of active tectonics during the Quaternary period. This study discusses the morpho-tectonics of the area and proposes an additional hydrological scheme to overcome the Sudd barrier through preventing water from flowing towards the low topography of the swamps region (Sudd Trough). Following the topographic gradient,the newly selected natural routes will dramatically increase the water budget of the Bahr El-Ghazal catchment and will support sustaining the currently proposed hydrological projects in the catchment

Qualitative and Quantitative Characterization of Municipal Waste in Uncontrolled Dumpsites and Landfills Using Integrated Remote Sensing, Geological and Geophysical Data: A Case Study

The conducted research offers an environmental assessment of municipal waste (MW) using remote sensing (RS), geological, and geophysical datasets. As a test site, the present study aims to characterize one of the largest uncontrolled dumpsites in Egypt. RS data analysis indicates that high temperature values are concentrated at the MW and landfill site allocations as a result of the decomposition process, leading to fire risks. Moreover, the geological and structural data draw attention to the structural-controlled old topography role on MW distributions. Consequently, the dumpsite MW has larger surface quantities near the downthrows of the mapped faults. For MW characterization, geophysical data are acquired to produce2D/3D resistivity models. Because MW has the ability to become soft clay, the municipal organic waste and landfill leachate resistivities are lower than that of municipal solid waste and sandy soils. The geophysical inversion results indicate that the maximum thickness of MW calibrating with the drilled borehole data is 60 m. Furthermore, the estimated MW dumpsite volume is about 42.32 MCM. Accordingly, the MW can be characterized in an accurate qualitative and quantitative manner. Our findings, therefore, help the efforts of uncontrolled dumpsite development and thus contribute to sustainability plans

Modeling Flash Floods and Induced Recharge into Alluvial Aquifers Using Multi-Temporal Remote Sensing and Electrical Resistivity Imaging

Flash flood hazard assessments, mitigation measures, and water harvesting efforts in desert environments are often challenged by data scarcity on the basin scale. The present study, using the Wadi Atfeh catchment as a test site, integrates remote sensing datasets with field and geoelectrical measurements to assess flash flood hazards, suggest mitigation measures, and to examine the recharge to the alluvium aquifer. The estimated peak discharge of the 13 March 2020 flood event was 97 m3/h, which exceeded the capacity of the culverts beneath the Eastern Military Highway (64 m3/h), and a new dam was suggested, where 75% of the catchment could be controlled. The monitoring of water infiltration into the alluvium aquifer using time-lapse electrical resistivity measurements along a fixed profile showed a limited connection between the wetted surficial sediments and the water table. Throughflow is probably the main source of recharge to the aquifer rather than vertical infiltration at the basin outlet. The findings suggest further measures to avoid the negative impacts of flash floods at the Wadi Atfeh catchment and similar basins in the Eastern Desert of Egypt. Furthermore, future hydrological studies in desert environments should take into consideration the major role of the throughflow in alluvium aquifer recharge

Toward an Integrated and Sustainable Water Resources Management in Structurally-Controlled Watersheds in Desert Environments Using Geophysical and Remote Sensing Methods

Sustainable water resources management in desert environment has yet to be reached due to the limited hydrological datasets under such extreme arid conditions. In the Eastern Sahara, the tectonic activity associated with the opening of the Red Sea adds more complexity to developing sustainable water management by creating multiple aquifers within subsided half-grabens along the Red Sea extension. To overcome these difficulties, a two-fold approach is adopted including integrated remote sensing and geoelectrical methods using Wadi Al-Ambagi watershed in the Eastern Desert of Egypt as a test site. First, the total discharge is estimated as 15.7 × 106 m3 following the application of a uniform storm of 10 mm effective precipitation, which exceeds the storage capacity of existing mitigation measures (5.5 × 106 m3), and thus additional dams are required. Second, the subsurface geometry of alluvium and sedimentary aquifers, within subsided blocks in the Arabian–Nubian shield (ANS), is delineated using 1D direct current and 2D electrical-resistivity tomography (ERT). Findings indicate that significant thicknesses of more than 80 m of permeable sedimentary units occur within the subsided blocks. Therefore, the scarce water resources can be managed by controlling the flash floods and suggesting proper dam sites at the location of thick alluvium and sedimentary rocks, where aquifers can be recharged representing a sustainable source for freshwater. The proposed approach is transferable and can be applied in similar arid rift-related watersheds in Saudi Arabia and worldwide