Tamer Gado currently is the head of the Department of Irrigation and Hydraulics Engineering, Tanta University, Egypt. His research in water resources management.
To achieve its ambitious plans to reclaim its deserts through mega projects, Egypt is heavily re... more To achieve its ambitious plans to reclaim its deserts through mega projects, Egypt is heavily relying on fossil or littlerecharged groundwater. This article revisits the results and methodologies of the studies onducted over the last two decades on groundwater management and uses in the Western Desert. Most previous studies aimed at simulating different groundwater abstraction scenarios by modeling local areas in aquifer systems, but with poor definitions of boundary conditions and limited historical data. Studies were constrained by the unavailability of data, access difficulties, and high collection costs in desert lands. Thus, to propose reliable sustainable groundwater resources development plans and recommendations for future protection strategies, an open-access monitoring network representing regional aquifers is needed. More nvestigations based on extensive field visits are essential to monitor environmental, economic, and social conditions, identify constraints, and learn lessons for reclaiming desert lands. Moreover, this review highlighted the need to frame a rational strategy for the long-term sustainable exploitation of non-renewable groundwater in the aquifer systems of Egypt and develop an appropriate exit strategy for desert communities in case of serious water resource depletion
Acque Sotterranee - Italian Journal of Groundwater
Saltwater intrusion (SWI) is a widespread environmental problem that poses a threat to coastal aq... more Saltwater intrusion (SWI) is a widespread environmental problem that poses a threat to coastal aquifers. To address this issue, this research employs both numerical and experimental methods to study saltwater intrusion under the impact of sea level rise and varying freshwater boundary conditions in two homogeneous aquifers. The study compares transient numerical groundwater heads and salt concentrations to experimental results under receding-front and advancing front conditions. In the low permeability aquifer, the root mean square error is 0.33 cm and the R2 is greater than 0.9817. Similarly, in the high permeability aquifer, the root mean square error is 0.92 cm and the R2 is greater than 0.9335. The study also compares the results of ten experimental tests for steady-state saltwater intrusion wedge and toe length with seven different analytical solutions. The experimental results are then compared to these analytical solutions to find the most suitable equation. The Rumer and Har...
Subsurface physical barriers have been effectively used to mitigate seawater intrusion (SWI). Tra... more Subsurface physical barriers have been effectively used to mitigate seawater intrusion (SWI). Traditionally, the primary emphasis in both numerical studies and practical implementations has been on vertical barriers. The current research aims to explore the dynamics of SWI under various cutoff-wall inclination angles and depths, as well as aquifer heterogeneity using both experimental and numerical simulations. The impact of aquifer characteristics was assessed by utilizing a low hydraulic conductivity (K) aquifer (case L), a high hydraulic conductivity aquifer (case H), and two stratified aquifers. The stratified aquifers were created by grouping different hydraulic conductivity layers into two cases: high K above low K (case H/L) and low K above high K (case L/H). The model simulations covered seven different cutoff-wall inclination angles: 45.0°, 63.4°, 76.0°, 90.0°, 104.0°, 116.6°, and 135.0°. The maximum repulsion ratio of SWI wedge length was observed at an inclination angle o...
One of the most prevalent and serious issues afflicting developing countries is the lack of adequ... more One of the most prevalent and serious issues afflicting developing countries is the lack of adequate space for waste disposal. Al-Gharbia Governorate, located in the middle of the Nile Delta in Egypt, suffers from random selection of sites for solid waste disposal, resulting in significant environmental challenges. The aim of this study is to determine optimal landfill locations within Al-Gharbia Governorate and validate the existing landfill sites. Four techniques of multi-criteria decision-making (MCDM) were applied to generate suitability maps for the Governorate: the analytical hierarchy procedure (AHP), ratio scale weighting (RSW), straight rank sum (SRS), and Boolean method. Eleven effective criteria were considered: groundwater, surface water, elevation, slope, soils, land use, roads, railways, urban areas, villages, and power lines. The suitability maps were categorized into four different classes: suitable, moderately suitable, low suitable, and unsuitable. The latest suitability map was determined by combining the results from the different methods, providing decision-makers with the means to select the optimal landfill site. The suitable zone encompasses a small area (3%), predominantly located in the northeast region (Al-Mahalla), central region (Tanta), and northern region (Kotour). Conversely, the unsuitable area covers a substantial portion (72.7%) due to the agricultural nature of the governorate, high population density, and elevated groundwater levels. Furthermore, all existing landfill sites fall within unsuitable or low suitable areas, inflicting severe impacts on the nearby environment, public health, and groundwater integrity.
The Egyptian Journal of Remote Sensing and Space Science, 2023
Moving towards horizontal expansion in the vast barren lands to alleviate overpopulation along th... more Moving towards horizontal expansion in the vast barren lands to alleviate overpopulation along the Nile River is imperative to Egypt’s 2030 sustainable development strategy. Accordingly, a mega reclamation project was advocated with a key goal of achieving food self-sufficiency. Solar-powered groundwater pumping system was adopted as the main water supply. Planning efforts are therefore inevitable to help locate the most favourable sites for such extensive cultivation activities. Herein, a multicriteria decision analysis was conducted to facilitate the zoning of potential rural communities across the northern portions of the Western Desert of Egypt. For this purpose, data of groundwater exploration, soil characterization, terrestrial accessibility, insolation intensity, and terrain information were fused to produce a high-resolution suitability map. The analytical hierarchy process approach was adopted to set the weighted importance of adopted criteria. The study area was categorized into Best, Good, Moderate, Fair, Poor, and Restricted classes at 1.7%, 13%, 42.6%, 26%, 10%, and 3%, respectively, of the entire region, while the constrained plots were masked out. The implemented and proposed wells fields within the underway national rural development project extend over agriculturally suitable pixels affirming the validity of the developed geospatial model. About 1.5 million ha, representing 7.2% of the undeveloped area, were found to be highly suitable for future expansion of agribusiness activities. The generated priority map will assist the decision-makers in the planning procedures for ongoing reclamation activities throughout Egypt.
An arid climate accompanied by a freshwater shortage plagued Egypt. It has resorted to groundwate... more An arid climate accompanied by a freshwater shortage plagued Egypt. It has resorted to groundwater reserves to meet the increasing water demands. Fossil aquifers were lately adopted as the sole water source to provide the irrigation water requirements of the ongoing reclamation activities in barren areas. Yet, the scarcity of measurements regarding the changes in the aquifers’ storage poses a great challenge to such sustainable resource management. In this context, the Gravity Recovery and Climate Experiment (GRACE) mission enables a novel consistent approach to deriving aquifers’ storage changes. In this study, the GRACE monthly solutions during the period 2003–2021 were utilized to estimate alterations in terrestrial water storage (TWS) throughout Egypt. Changes in groundwater storage (GWS) were inferred by subtracting soil water content, derived from the GLDAS-NOAH hydrological model, from the retrieved TWS. The secular trends in TWS and GWS were obtained using the linear least s...
This research was carried out in order to develop better methods for improving the accuracy of fl... more This research was carried out in order to develop better methods for improving the accuracy of flood estimation. The first part of the thesis deals with the estimation of floods at ungauged sites. At the beginning, a comparative study was done to determine the best approach for delineating homogeneous regions. Three approaches were considered in this study: (1) the scaling method, which is based on the scaling behaviour of the flood series with the basin area; (2) the region of influence (ROI); and (3) the canonical correlation analysis (CCA). Analyses of hydrologic data from Quebec have indicated that the annual maximum series (AMS) exhibited a simple scaling behaviour. Results of this numerical application have indicated that the flood quantile estimates obtained from the scaling approach were more accurate and more robust than those given by the ROI or CCA methods. Then, a regional index-flood method for ungauged sites based on the partial duration series (PDS) method and the sca...
This study analyzed rainfall projections in Egypt throughout the current century in the context o... more This study analyzed rainfall projections in Egypt throughout the current century in the context of climate change. Three common bias-correction methods were applied to adjust regional climate model (RCM) simulations of precipitation regarding the observed daily rainfall data of 15 locations in Egypt. The results revealed that the empirical quantile mapping was the most appropriate method to correct the projection of rainfall indices. The projected changes in rainfall showed significant increases at most locations for all future scenarios. The western part of the country will be the most affected by climate change, anticipating a significant increase in precipitation, in contrast to the regions of the Nile Valley, Delta, and the Northern Coast, which may witness a decrease in precipitation and an increase in meteorological drought. Under the worst-case scenario, the rate of increase in rainfall indices over the country is expected to decline during the last decade of the century. The...
The extreme rainfall events have critical impacts on hydrologic systems and the society, especial... more The extreme rainfall events have critical impacts on hydrologic systems and the society, especially in arid countries. Recently, Egypt has been subject to some flash floods, due to extreme rainfall events, in particular regions (e.g., Sinai, North Coast, and Upper Egypt) that caused severe damages in lives and vital infrastructure and buildings. This chapter investigates, therefore, the statistical characteristics of rainfall over Egypt based on historical daily rainfall records at 30 stations throughout the country. Six types of rainfall data were extracted from daily records: monthly rainfall, annual rainfall, the monthly number of rainy days, the annual number of rainy days, monthly maximum daily rainfall, and annual maximum daily rainfall. Rainfall frequency analysis, based on the generalized extreme value (GEV) distribution along with the L-moments parameter estimation method, was applied to analyze annual maximum rainfall series. Results of the numerical application indicate a great variation over the whole country in all different aspects of rainfall. The rainfall indices have higher values in the north of the country than those in the middle and the south. Also, the annual maximum daily rainfall data in the case study has been well described by the GEV distribution with negative values of the shape parameter for all stations except only one station (Ras Sedr).
Recently, it has been recognized that society as a whole has become more vulnerable to extreme we... more Recently, it has been recognized that society as a whole has become more vulnerable to extreme weather and flood events. This paper investigates therefore the variability of flood peaks in Quebec (Canada) based on a detailed statistical analysis of the historical annual maximum flow (AMF) records. Firstly, temporal trends in the mean of flood peaks were examined. Then, the significance of the detected trends over the whole region was assessed. It was found that a quarter of the analyzed stations show significant trends in the AMF. Particularly, all of the significant trends are negative, indicating decreasing flood magnitudes in Quebec.
Abstract In hydraulic structures design, using cutoff walls is essential to reduce and control th... more Abstract In hydraulic structures design, using cutoff walls is essential to reduce and control the resultant uplift force (U), seepage discharge (Q), and exit hydraulic gradient (i). This research investigates the effectiveness of inclined double cutoff walls under hydraulic structures, considering the influence of depths, locations, and inclination angles of the upstream and downstream cutoff walls by using Finite Element Method (FEM). The results confirmed that installing a deeper cutoff wall on the downstream reduces the exit gradient even further. In the case of the cutoff walls located in the upstream and downstream ends, the exit gradient will be less than when the cutoff walls are installed at a closer distance. Increasing the inclination angle of downstream cutoff wall has a major impact on exit gradient reduction. Embedment of cutoff walls in the upstream and downstream ends with right angles and equal depths reduces the seepage discharge more than other cases.
Environmental Science and Pollution Research, 2021
This study projected the future temperature change for Egypt during the late of this century (207... more This study projected the future temperature change for Egypt during the late of this century (2071–2100) for three representative concentration pathways (RCP2.6, RCP4.5, and RCP8.5), by correcting regional climate model (RCM) simulations of average, maximum, and minimum daily temperature with reference to observed data of 26 stations. Four commonly used methods of bias correction have been applied and evaluated: linear scaling, variance scaling, and theoretical and empirical quantile mapping. The compromise programing results of the applied evaluation criteria show that the best method is the variance scaling, and thus it was applied to transfer the correction factor to the projections. All temperature indices are expected to increase significantly under all scenarios and reach the highest record by the end of the century, i.e., the expected increase in average, maximum, and minimum temperature ranges between 4.08–7.41 °C, 4.55–7.89 °C, and 3.88–7.23 °C, respectively. The largest temperature rise will occur in the summer, with the highest increase in the maximum (minimum) temperature of 10.9 °C (10 °C) in July and August under RCP8.5. The maximum (minimum) winter temperature, on the other hand, will drop by a maximum of 2 °C (1.35 °C) under RCP2.6. The Western Desert and Upper Egypt are the regions most affected by climate change, while the northern region of Egypt is the least affected. These findings would help in impact assessment and adaptation strategies and encourage further investigation to evaluate various climate models in order to obtain a comprehensive assessment of the climate change impacts on different hydrometeorological processes in Egypt.
Recently, it has been recognized that society as a whole has become more vulnerable to extreme we... more Recently, it has been recognized that society as a whole has become more vulnerable to extreme weather and flood events. This paper investigates therefore the variability of flood peaks in Quebec (Canada) based on a detailed statistical analysis of the historical annual maximum flow (AMF) records. Firstly, temporal trends in the mean of flood peaks were examined. Then, the significance of the detected trends over the whole region was assessed. It was found that a quarter of the analyzed stations show significant trends in the AMF. Particularly, all of the significant trends are negative, indicating decreasing flood magnitudes in Quebec.
To achieve its ambitious plans to reclaim its deserts through mega projects, Egypt is heavily re... more To achieve its ambitious plans to reclaim its deserts through mega projects, Egypt is heavily relying on fossil or littlerecharged groundwater. This article revisits the results and methodologies of the studies onducted over the last two decades on groundwater management and uses in the Western Desert. Most previous studies aimed at simulating different groundwater abstraction scenarios by modeling local areas in aquifer systems, but with poor definitions of boundary conditions and limited historical data. Studies were constrained by the unavailability of data, access difficulties, and high collection costs in desert lands. Thus, to propose reliable sustainable groundwater resources development plans and recommendations for future protection strategies, an open-access monitoring network representing regional aquifers is needed. More nvestigations based on extensive field visits are essential to monitor environmental, economic, and social conditions, identify constraints, and learn lessons for reclaiming desert lands. Moreover, this review highlighted the need to frame a rational strategy for the long-term sustainable exploitation of non-renewable groundwater in the aquifer systems of Egypt and develop an appropriate exit strategy for desert communities in case of serious water resource depletion
Acque Sotterranee - Italian Journal of Groundwater
Saltwater intrusion (SWI) is a widespread environmental problem that poses a threat to coastal aq... more Saltwater intrusion (SWI) is a widespread environmental problem that poses a threat to coastal aquifers. To address this issue, this research employs both numerical and experimental methods to study saltwater intrusion under the impact of sea level rise and varying freshwater boundary conditions in two homogeneous aquifers. The study compares transient numerical groundwater heads and salt concentrations to experimental results under receding-front and advancing front conditions. In the low permeability aquifer, the root mean square error is 0.33 cm and the R2 is greater than 0.9817. Similarly, in the high permeability aquifer, the root mean square error is 0.92 cm and the R2 is greater than 0.9335. The study also compares the results of ten experimental tests for steady-state saltwater intrusion wedge and toe length with seven different analytical solutions. The experimental results are then compared to these analytical solutions to find the most suitable equation. The Rumer and Har...
Subsurface physical barriers have been effectively used to mitigate seawater intrusion (SWI). Tra... more Subsurface physical barriers have been effectively used to mitigate seawater intrusion (SWI). Traditionally, the primary emphasis in both numerical studies and practical implementations has been on vertical barriers. The current research aims to explore the dynamics of SWI under various cutoff-wall inclination angles and depths, as well as aquifer heterogeneity using both experimental and numerical simulations. The impact of aquifer characteristics was assessed by utilizing a low hydraulic conductivity (K) aquifer (case L), a high hydraulic conductivity aquifer (case H), and two stratified aquifers. The stratified aquifers were created by grouping different hydraulic conductivity layers into two cases: high K above low K (case H/L) and low K above high K (case L/H). The model simulations covered seven different cutoff-wall inclination angles: 45.0°, 63.4°, 76.0°, 90.0°, 104.0°, 116.6°, and 135.0°. The maximum repulsion ratio of SWI wedge length was observed at an inclination angle o...
One of the most prevalent and serious issues afflicting developing countries is the lack of adequ... more One of the most prevalent and serious issues afflicting developing countries is the lack of adequate space for waste disposal. Al-Gharbia Governorate, located in the middle of the Nile Delta in Egypt, suffers from random selection of sites for solid waste disposal, resulting in significant environmental challenges. The aim of this study is to determine optimal landfill locations within Al-Gharbia Governorate and validate the existing landfill sites. Four techniques of multi-criteria decision-making (MCDM) were applied to generate suitability maps for the Governorate: the analytical hierarchy procedure (AHP), ratio scale weighting (RSW), straight rank sum (SRS), and Boolean method. Eleven effective criteria were considered: groundwater, surface water, elevation, slope, soils, land use, roads, railways, urban areas, villages, and power lines. The suitability maps were categorized into four different classes: suitable, moderately suitable, low suitable, and unsuitable. The latest suitability map was determined by combining the results from the different methods, providing decision-makers with the means to select the optimal landfill site. The suitable zone encompasses a small area (3%), predominantly located in the northeast region (Al-Mahalla), central region (Tanta), and northern region (Kotour). Conversely, the unsuitable area covers a substantial portion (72.7%) due to the agricultural nature of the governorate, high population density, and elevated groundwater levels. Furthermore, all existing landfill sites fall within unsuitable or low suitable areas, inflicting severe impacts on the nearby environment, public health, and groundwater integrity.
The Egyptian Journal of Remote Sensing and Space Science, 2023
Moving towards horizontal expansion in the vast barren lands to alleviate overpopulation along th... more Moving towards horizontal expansion in the vast barren lands to alleviate overpopulation along the Nile River is imperative to Egypt’s 2030 sustainable development strategy. Accordingly, a mega reclamation project was advocated with a key goal of achieving food self-sufficiency. Solar-powered groundwater pumping system was adopted as the main water supply. Planning efforts are therefore inevitable to help locate the most favourable sites for such extensive cultivation activities. Herein, a multicriteria decision analysis was conducted to facilitate the zoning of potential rural communities across the northern portions of the Western Desert of Egypt. For this purpose, data of groundwater exploration, soil characterization, terrestrial accessibility, insolation intensity, and terrain information were fused to produce a high-resolution suitability map. The analytical hierarchy process approach was adopted to set the weighted importance of adopted criteria. The study area was categorized into Best, Good, Moderate, Fair, Poor, and Restricted classes at 1.7%, 13%, 42.6%, 26%, 10%, and 3%, respectively, of the entire region, while the constrained plots were masked out. The implemented and proposed wells fields within the underway national rural development project extend over agriculturally suitable pixels affirming the validity of the developed geospatial model. About 1.5 million ha, representing 7.2% of the undeveloped area, were found to be highly suitable for future expansion of agribusiness activities. The generated priority map will assist the decision-makers in the planning procedures for ongoing reclamation activities throughout Egypt.
An arid climate accompanied by a freshwater shortage plagued Egypt. It has resorted to groundwate... more An arid climate accompanied by a freshwater shortage plagued Egypt. It has resorted to groundwater reserves to meet the increasing water demands. Fossil aquifers were lately adopted as the sole water source to provide the irrigation water requirements of the ongoing reclamation activities in barren areas. Yet, the scarcity of measurements regarding the changes in the aquifers’ storage poses a great challenge to such sustainable resource management. In this context, the Gravity Recovery and Climate Experiment (GRACE) mission enables a novel consistent approach to deriving aquifers’ storage changes. In this study, the GRACE monthly solutions during the period 2003–2021 were utilized to estimate alterations in terrestrial water storage (TWS) throughout Egypt. Changes in groundwater storage (GWS) were inferred by subtracting soil water content, derived from the GLDAS-NOAH hydrological model, from the retrieved TWS. The secular trends in TWS and GWS were obtained using the linear least s...
This research was carried out in order to develop better methods for improving the accuracy of fl... more This research was carried out in order to develop better methods for improving the accuracy of flood estimation. The first part of the thesis deals with the estimation of floods at ungauged sites. At the beginning, a comparative study was done to determine the best approach for delineating homogeneous regions. Three approaches were considered in this study: (1) the scaling method, which is based on the scaling behaviour of the flood series with the basin area; (2) the region of influence (ROI); and (3) the canonical correlation analysis (CCA). Analyses of hydrologic data from Quebec have indicated that the annual maximum series (AMS) exhibited a simple scaling behaviour. Results of this numerical application have indicated that the flood quantile estimates obtained from the scaling approach were more accurate and more robust than those given by the ROI or CCA methods. Then, a regional index-flood method for ungauged sites based on the partial duration series (PDS) method and the sca...
This study analyzed rainfall projections in Egypt throughout the current century in the context o... more This study analyzed rainfall projections in Egypt throughout the current century in the context of climate change. Three common bias-correction methods were applied to adjust regional climate model (RCM) simulations of precipitation regarding the observed daily rainfall data of 15 locations in Egypt. The results revealed that the empirical quantile mapping was the most appropriate method to correct the projection of rainfall indices. The projected changes in rainfall showed significant increases at most locations for all future scenarios. The western part of the country will be the most affected by climate change, anticipating a significant increase in precipitation, in contrast to the regions of the Nile Valley, Delta, and the Northern Coast, which may witness a decrease in precipitation and an increase in meteorological drought. Under the worst-case scenario, the rate of increase in rainfall indices over the country is expected to decline during the last decade of the century. The...
The extreme rainfall events have critical impacts on hydrologic systems and the society, especial... more The extreme rainfall events have critical impacts on hydrologic systems and the society, especially in arid countries. Recently, Egypt has been subject to some flash floods, due to extreme rainfall events, in particular regions (e.g., Sinai, North Coast, and Upper Egypt) that caused severe damages in lives and vital infrastructure and buildings. This chapter investigates, therefore, the statistical characteristics of rainfall over Egypt based on historical daily rainfall records at 30 stations throughout the country. Six types of rainfall data were extracted from daily records: monthly rainfall, annual rainfall, the monthly number of rainy days, the annual number of rainy days, monthly maximum daily rainfall, and annual maximum daily rainfall. Rainfall frequency analysis, based on the generalized extreme value (GEV) distribution along with the L-moments parameter estimation method, was applied to analyze annual maximum rainfall series. Results of the numerical application indicate a great variation over the whole country in all different aspects of rainfall. The rainfall indices have higher values in the north of the country than those in the middle and the south. Also, the annual maximum daily rainfall data in the case study has been well described by the GEV distribution with negative values of the shape parameter for all stations except only one station (Ras Sedr).
Recently, it has been recognized that society as a whole has become more vulnerable to extreme we... more Recently, it has been recognized that society as a whole has become more vulnerable to extreme weather and flood events. This paper investigates therefore the variability of flood peaks in Quebec (Canada) based on a detailed statistical analysis of the historical annual maximum flow (AMF) records. Firstly, temporal trends in the mean of flood peaks were examined. Then, the significance of the detected trends over the whole region was assessed. It was found that a quarter of the analyzed stations show significant trends in the AMF. Particularly, all of the significant trends are negative, indicating decreasing flood magnitudes in Quebec.
Abstract In hydraulic structures design, using cutoff walls is essential to reduce and control th... more Abstract In hydraulic structures design, using cutoff walls is essential to reduce and control the resultant uplift force (U), seepage discharge (Q), and exit hydraulic gradient (i). This research investigates the effectiveness of inclined double cutoff walls under hydraulic structures, considering the influence of depths, locations, and inclination angles of the upstream and downstream cutoff walls by using Finite Element Method (FEM). The results confirmed that installing a deeper cutoff wall on the downstream reduces the exit gradient even further. In the case of the cutoff walls located in the upstream and downstream ends, the exit gradient will be less than when the cutoff walls are installed at a closer distance. Increasing the inclination angle of downstream cutoff wall has a major impact on exit gradient reduction. Embedment of cutoff walls in the upstream and downstream ends with right angles and equal depths reduces the seepage discharge more than other cases.
Environmental Science and Pollution Research, 2021
This study projected the future temperature change for Egypt during the late of this century (207... more This study projected the future temperature change for Egypt during the late of this century (2071–2100) for three representative concentration pathways (RCP2.6, RCP4.5, and RCP8.5), by correcting regional climate model (RCM) simulations of average, maximum, and minimum daily temperature with reference to observed data of 26 stations. Four commonly used methods of bias correction have been applied and evaluated: linear scaling, variance scaling, and theoretical and empirical quantile mapping. The compromise programing results of the applied evaluation criteria show that the best method is the variance scaling, and thus it was applied to transfer the correction factor to the projections. All temperature indices are expected to increase significantly under all scenarios and reach the highest record by the end of the century, i.e., the expected increase in average, maximum, and minimum temperature ranges between 4.08–7.41 °C, 4.55–7.89 °C, and 3.88–7.23 °C, respectively. The largest temperature rise will occur in the summer, with the highest increase in the maximum (minimum) temperature of 10.9 °C (10 °C) in July and August under RCP8.5. The maximum (minimum) winter temperature, on the other hand, will drop by a maximum of 2 °C (1.35 °C) under RCP2.6. The Western Desert and Upper Egypt are the regions most affected by climate change, while the northern region of Egypt is the least affected. These findings would help in impact assessment and adaptation strategies and encourage further investigation to evaluate various climate models in order to obtain a comprehensive assessment of the climate change impacts on different hydrometeorological processes in Egypt.
Recently, it has been recognized that society as a whole has become more vulnerable to extreme we... more Recently, it has been recognized that society as a whole has become more vulnerable to extreme weather and flood events. This paper investigates therefore the variability of flood peaks in Quebec (Canada) based on a detailed statistical analysis of the historical annual maximum flow (AMF) records. Firstly, temporal trends in the mean of flood peaks were examined. Then, the significance of the detected trends over the whole region was assessed. It was found that a quarter of the analyzed stations show significant trends in the AMF. Particularly, all of the significant trends are negative, indicating decreasing flood magnitudes in Quebec.
5 th International Scientific Research conference: Renewable Energy & Water Sustainability, 26 29 March 2019 , Sharm El Sheikh, Egypt., 2019
Egypt’s limited water resources, rapid population growth, and climate change are increasing the g... more Egypt’s limited water resources, rapid population growth, and climate change are increasing the gap between water demand and supply. Meanwhile, significant amounts of rain fall in some regions in Egypt during specific storm events, which in some cases, lead to disasters like flash floods and inundations. Rainwater harvesting (RWH) can be considered as a sustainable promising solution to water shortage and inundation problems. In this work, the feasibility of RWH for urban areas was assessed over 22 cities throughout Egypt. Results show that the annual volume of rainwater harvested can reach 142.5 MCM in the considered cities, provided that all rain falling on the urban areas is collected. High potential of rainfall harvesting was found for cities that located on the North Coast, e.g., the potential water saving from the share of RWH in Alexandria can satisfy around 12% of its future supplementary domestic water needs. In contrast, rainfall over the cities located on the middle and the south of the country is insignificant to be harvested. A case study for the 5th settlement region in Cairo was discussed in terms of groundwater recharge and surface runoff estimation for two conditions: No–RWH and RWH systems by implementing recharge wells to store rainwater into the aquifer. Land cover classification maps of urban areas were created by using the ARCGIS software to estimate equivalent infiltration coefficients. The results demonstrate that the implementation of such RWH system has a significant impact on the regional water cycle, where the effective infiltration coefficient increased from10%(No–RWH) to 75%(RWH) in the case study. Accordingly, the runoff coefficient decreased in the case study from 0.8 (No–RWH) to 0.15 (RWH), and the volume of runoff decreased in the case of RWH by around 82% lower than that of the No–RWH condition. Thus, direct infiltration of RWH into an aquifer can play an important role in sound water management for urban environments, as this may lead to a significant reduction in risks of flooding and expenses of municipal drainage systems installation and operation.
One of the main obstacles in making reliable predictions of extreme events is the apparent shortn... more One of the main obstacles in making reliable predictions of extreme events is the apparent shortness of the time series available in hydrology. There is a common advantage of both regional flood-frequency analysis and partial duration series (PDS) in which both of them allow a reduction of uncertainty by introducing more data to the site of interest. Therefore, a new regional index flood method for ungauged sites based on the PDS model is presented. The PDS model considered in this case assumes a Poisson-distributed number of threshold exceedances and generalized Pareto-distributed peak magnitudes. A new objective approach for the selection of the threshold in the context of regionalization is introduced. This approach estimates a range of reasonable thresholds (or an average annual number of events) for every site. Consequently, the regional average annual number of events can be determined as a common value for all sites in the homogeneous region. The delineation of hydrologically homogeneous regions is determined using the scaling approach. The feasibility of the proposed method was assessed using the available daily flow series from 57 watersheds in Quebec (Canada). Furthermore, the new method is compared with two existing methods for regionalization: the region of influence and canonical correlation analysis methods. Results of the numerical application indicate that the quantile estimates obtained from the new method provide the best values of the performance criteria (e.g., rootmean- square error). Hence, the new method not only eliminates subjective decisions but also greatly improves the predicted floods for ungauged sites.
The occurrence of floods and their impacts on hydrologic systems and society are critical conside... more The occurrence of floods and their impacts on hydrologic systems and society are critical considerations in the design and management of a large number of water resources projects. As streamflow records are often limited or unavailable at many watersheds, it is necessary to develop better methods for regional estimation of floods at these partially-gauged or ungauged sites. In this paper, a comparative study of homogeneous region delineation approaches in the context of regional flood quantile estimation is presented. Three approaches were considered in this study using the available annual maximum series (AMS) of flood peaks for 57 watersheds in Québec, Canada. The first approach was the scaling method, which is a relatively new approach for homogeneous region delineation. This approach is based on the scaling behavior of the flood series with the basin area. The other two approaches were the region of influence (ROI) and canonical correlation analysis (CCA) methods. Regional flood estimation was carried out using the index flood method. The jackknife technique was used to represent the ungauged site condition. Analyses of hydrologic data from Québec have indicated that the AMS exhibited a simple scaling behavior and that the drainage area alone may describe most of the variability in the statistical moments of the AMS data. Results of this numerical application have found that the flood quantile estimates obtained from the scaling approach are more accurate and more robust than those given by the ROI or CCA methods. In addition, it was found that the grouping of similar basins on the basis of the scaling approach formed well-defined geographical regions with distinct climatic characteristics.
Recently, it has been recognized that society as a whole has become more vulnerable to extreme we... more Recently, it has been recognized that society as a whole has become more vulnerable to extreme weather and flood events. This paper investigates therefore the variability of flood peaks in Quebec (Canada) based on a detailed statistical analysis of the historical annual maximum flow (AMF) records. Firstly, temporal trends in the mean of flood peaks were examined. Then, the significance of the detected trends over the whole region was assessed. It was found that a quarter of the analyzed stations show significant trends in the AMF. Particularly, all of the significant trends are negative, indicating decreasing flood magnitudes in Quebec.
The extreme rainfall events have critical impacts on
hydrologic systems and the society, especial... more The extreme rainfall events have critical impacts on hydrologic systems and the society, especially in arid countries. Recently, Egypt has been subject to some flash floods, due to extreme rainfall events, in particular regions (e.g., Sinai, North Coast, and Upper Egypt) that caused severe damages in lives and vital infrastructure and buildings. This chapter investigates, therefore, the statistical characteristics of rainfall over Egypt based on historical daily rainfall records at 30 stations throughout the country. Six types of rainfall data were extracted from daily records: monthly rainfall, annual rainfall, the monthly number of rainy days, the annual number of rainy days, monthly maximum daily rainfall, and annual maximum daily rainfall. Rainfall frequency analysis, based on the generalized extreme value (GEV) distribution along with the L-moments parameter estimation method, was applied to analyze annual maximum rainfall series. Results of the numerical application indicate a great variation over the whole country in all different aspects of rainfall. The rainfall indices have higher values in the north of the country than those in the middle and the south. Also, the annual maximum daily rainfall data in the case study has been well described by the GEV distribution with negative values of the shape parameter for all stations except only one station (Ras Sedr).
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Papers by Tamer A Gado
hydrology. There is a common advantage of both regional flood-frequency analysis and partial duration series (PDS) in which both of them allow a reduction of uncertainty by introducing more data to the site of interest. Therefore, a new regional index flood method for ungauged sites based on the PDS model is presented. The PDS model considered in this case assumes a Poisson-distributed number of threshold exceedances and generalized Pareto-distributed peak magnitudes. A new objective approach for the selection of the threshold in the context of regionalization is introduced. This approach estimates a range of reasonable thresholds (or an average annual number of events) for every site. Consequently, the regional average annual number of events can be determined as a common value for all sites in the homogeneous region. The delineation of hydrologically homogeneous regions is determined using the scaling approach. The feasibility of the proposed method was assessed using the available daily flow series from 57 watersheds in Quebec (Canada). Furthermore, the new method is compared with two existing methods for regionalization: the region of influence and canonical correlation analysis methods. Results of the numerical application indicate that the quantile estimates obtained from the new method provide the best values of the performance criteria (e.g., rootmean- square error). Hence, the new method not only eliminates subjective decisions but also greatly improves the predicted floods for
ungauged sites.
hydrologic systems and the society, especially in arid
countries. Recently, Egypt has been subject to some flash
floods, due to extreme rainfall events, in particular
regions (e.g., Sinai, North Coast, and Upper Egypt) that
caused severe damages in lives and vital infrastructure
and buildings. This chapter investigates, therefore, the
statistical characteristics of rainfall over Egypt based on
historical daily rainfall records at 30 stations throughout
the country. Six types of rainfall data were extracted from
daily records: monthly rainfall, annual rainfall, the
monthly number of rainy days, the annual number of
rainy days, monthly maximum daily rainfall, and annual
maximum daily rainfall. Rainfall frequency analysis,
based on the generalized extreme value (GEV) distribution
along with the L-moments parameter estimation method,
was applied to analyze annual maximum rainfall series.
Results of the numerical application indicate a great
variation over the whole country in all different aspects of
rainfall. The rainfall indices have higher values in the
north of the country than those in the middle and the
south. Also, the annual maximum daily rainfall data in the
case study has been well described by the GEV distribution
with negative values of the shape parameter for all
stations except only one station (Ras Sedr).