Understanding and modeling a dam breaching process is an essential investigation, because it aims to minimize the flood’s hazards, and its impact on people and structures, using suitable mitigation plans. In the current study, three-dimensional numerical modeling is carried out using the FLOW-3D HYDRO program to investigate the impact of various factors, including the dam grain size materials, crest width, inflow discharge, and tail water depth on the dam breach process, particularly the peak outflow, and the erosion rate. The results show that changing the grain size of the dam material from fine sand to medium and coarse sand leads to an increase in the peak outflow discharge by 16.0% and the maximum erosion rate by 20.0%. Furthermore, increasing the dam crest width by 40% leads to a decrease in the peak outflow by 3.0% and the maximum erosion rates by 4.50%. Moreover, increasing the inflow discharge by 25.0% increases the peak outflow by 23.0% and the maximum erosion rates by 21.0%. Finally, increasing the tail water depth by 50.0% leads to decreasing the peak outflow by 4.50% and the maximum erosion rate by 43.0%. The study findings are considered of high importance for dam design and operation control. Moreover, the results can be applied for the optimum determination of the crest width and tail water depth that leads to improving the dam stability.

Dams are built for different purposes, but failure of a dam could result in extreme disasters such as floods. The Grand Ethiopian Renaissance Dam (GERD) was mainly built for power generation, but concerns about its safety, location and site conditions have led the downstream countries to investigate the GERD’s stability. This paper aims to investigate the impact of the failure of the dam on the downstream countries using the Hydrologic Engineering Center River Analysis System (HEC-RAS). Outflow hydrographs and flood inundation maps were provided through a hypothetical dam break scenario. An unsteady flow hydrodynamic routing with a 2D model was used to simulate the failure of the dam. A sensitivity analysis study of the output’s findings against breach parameters was also performed. The breach outflow discharge increases as the breach dimension increases. However, the peak discharge decreases with increasing breach formation time. Moreover, to prepare emergency action plans, it is important to predict the inundation depth, levels, arrival of flood waves, flood coverage area and water velocity. Furthermore, the results showed that Khartoum would turn into lakes within about 10 days and flood water depth would exceed 11 m at some locations in residential areas. Moreover, the flood waves overtopped the Roseires, Sennar and Merowe dams by 11, 7 and 20 m, respectively. In addition, the level of Lake Nasser would reach 188 m above sea level and the Aswan High Dam might be in great danger.

Despite significant improvements in design methodologies, dams and water-retaining structures failures continue to occur. Dams’ failure analysis plays a crucial role in the development of dam safety planning and emergency action. Since the Grand Ethiopian Renaissance Dam (GERD) has been built, there have been many concerns about its safety and its effects on downstream countries in case of its failure. In this paper, the GERD break was modeled by using the USACE Hydrologic Engineering Center’s River Analysis System (HEC-RAS). Two dimensions model under different failure scenarios was suggested. Moreover, outflow hydrographs and flood inundation maps were presented due to dam breach. Finally, it was concluded that, in case of catastrophic failure, flow depths may vary from 3 to 10 m in some residential areas, such as Khartoum. Furthermore, the water surface elevation may reach 184 m above msl (mean sea level) in Lake Nasser in case of dam failure with a fully stored GERD reservoir. Moreover, the maximum flow would reach 325,928 m3/sec which is more than 21.5 times the total capacity of the dam spillway. Finally, the paper’s outcomes may assist decision-makers in developing alternate plans to deal with the dangers of GERD break.

Jazan province on Saudi Arabia’s southwesterly Red Sea coast is facing significant challenges in water management related to its arid climate, restricted water resources, and increasing population. A total of 180 groundwater samples were collected and tested for important hydro-chemical parameters used to determine its adaptability for irrigation. The principal components analysis (PCA) was applied to evaluate the consistency/cluster overlapping, agglomeration in the datasets, and to identify the sources of variation between the 11 major ion concentrations (pH, K+, Na+, Mg2+, Ca2+, SO42−, Cl−, HCO3−, NO3−, TDS, and TH). The EC values ranged from excellent to unsuitable, with 10% being excellent to good, 43% permissible, and 47% improper for irrigation. The SAR classification determined that 91.67% of groundwater samples were good to excellent for irrigation, indicating that they are suitable for irrigation with no sodium-related adverse effects. Magnesium hazard values showed that 1.67% of the samples are unsuitable for irrigation, while the remaining 98.33% are suitable. Chloro-alkaline indices signify that most groundwater samples show positive ratios indicating that ion exchange is dominant in the aquifer. The Gibb’s diagram reflects that evaporation, seawater interaction, and water–rock interaction are the foremost processes impacting groundwater quality, besides other regional environmental variables. A strong positive correlation was declared between TDS and Na+, Mg2+, Ca2+, Cl−, SO42− in addition to TH with Mg2+, Ca2+, Cl−, SO42−, TDS, and also Cl− with Na+, Ca2+, Mg2+ were major connections, with correlation coefficients over 0.8 and p < 0.0001. The extracted factor analysis observed that TH, Ca2+, TDS, Cl−, and Mg2+ have high positive factor loading in Factor 1, with around 52% of the total variance. This confirms the roles of evaporation and ion exchange as the major processes that mostly affect groundwater quality, along with very little human impact. The spatial distribution maps of the various water quality indices showed that the majority of unsuitable groundwater samples were falling along the coast where there is overcrowding and a variety of anthropogenic activities and the possible impact of seawater intrusion. The results of the hierarchical cluster analysis agreed with the correlations mentioned in the factor analysis and correlation matrix. As a result, incorporating physicochemical variables into the PCA to assess groundwater quality is a practical and adaptable approach with exceptional abilities and new perspectives. According to the study’s findings, incorporating different techniques to assess groundwater quality is beneficial in understanding the factors that control groundwater quality and can assist officials in effectively controlling groundwater quality and also enhancing the water resources in the study area.

Flash floods threaten the lives of people and properties in different regions around the world, especially in arid and semi-arid regions due to infrequent flood events. The current study aims to assess the geomorphological parameters of Wadi Sudr, South Sinai in Egypt to evaluate flash flood risks and provide adequate mitigation methods. This study presents an integrated method that combines geographic information system (GIS) and watershed modeling system (WMS) with HEC-HMS to visualize and assess flood events in the study area. Different morphologic parameters of the watershed were determined, including linear, areal, and relief parameters. GIS was used to analyze the satellite images and determine the characteristics of the valley to get the extension and number of stream orders in the valley, then WMS was used to estimate rainstorms and basin characteristics, as well as estimate the amount of rain that causes flooding. HEC-HMS program was used for hydrological demonstration and precipitation overflow estimation. The morphometric analysis provided a quantitative portrayal of the Wadi Sudr watershed. Wadi Sudr has 4029 streams connected with seventh order of streams spread over an area of 547.45 km(2). Based on the results of morphologic and hydraulic parameters of the watershed, two locations of protection dams were suggested. A comparison between the two locations was made to select the best location based on some criteria, including storage capacity, water depth behind the dam, width and shape of the valley, and the area covered by water stored in the reservoir. The comparison between the two locations showed that the first location is more appropriate for dam construction based on the examined criteria. The valley shape in the first location is more regular than in the second. The first location provided higher storage capacity and water depth in front of the dam than the second. The area covered by water and the width of the valley is less than the second. The stability of the dam at the first site could be higher and the cost of construction could cost be less than the second due to these reasons. A comparison was made using the weighted linear combination (WLC) method, which consists of 13 criteria to determine the suitability index (SI) in order to select the best location from the proposed locations. SI proved that the first location is better than the second. The designed dam in the selected site could be cost-efficient to protect the study area from flood risks and harvesting water that can be used in different purposes. This methodology can be applied in different areas for mitigating flash flood risks.

Egypt's current water security situation is weak, having a deficit of about 30 billion cubic metres of water. Many alternatives have been introduced to face water scarcity. Developing water control structures is an important solution to manage water resources. Egyptian Ministry of Water Resources and Irrigation intended to replace the existing regulators at Dairut city with a new one. A design requirement for the new barrage is that water levels in front of the existing barrages will be approximately 0.60 m higher than the present one. This may cause a rise in groundwater levels, which lead to an increase in the seepage flow from the canals surrounding the new project. The main goal of this study is to assess the surface and groundwater interaction using field measurements and water quality for the area around the project of New Dairut Group Regulators (NDGRs). Furthermore, thirteen piezometers have been installed in the study area to measure groundwater levels and quality. Results showed that a confined aquifer is underlying the study area and there is a hydraulic connection between surface water and groundwater. The results showed that there is a decline in water level at wells W2 and W10 during the winter closure by 2.2 m and 2.0 m respectively when the water level of Ibrahimia canal at the upstream of DGRs decreased by 3.7 m, which indicated that the aquifer was connected hydraulically with canals. Water quality results indicated that about 61.5% of the groundwater samples are slightly saline (TDS > 1000 mg/l), while 38.5% of the samples are freshwater with TDS < 1000 mg/l. The factor analysis produced three factors, which described 93.69% of the total variance. The results show that the concentrations of pH do not donate to all other parameters. This study recommended that a sewerage system is needed to protect groundwater from contamination in the study area.

Stability of canals slopes are of paramount importance in engineering works due to its interaction with the infrastructure including roads networks and buildings. The failure of these slopes could cause human disaster, catastrophic environmental, and economic losses. The present study aims to investigate the stability of canals slopes considering the climate changes through sea level rise, fluctuation of groundwater level and the seismic actions. The study was simulated on the North Eastern part of Nile Delta aquifer, Egypt using the finite difference code of Visual MODFLOW. Moreover, the groundwater flow under the effect of sea level rise was investigated to study its effect on slope stability of El-Salam Canal, Egypt. Furthermore, the finite element program of Phase 2 was implemented, and safety factors were calculated using the shear strength reduction method (SSRM). The models are calibrated and verified through experimental work using permeability and seepage model. Moreover, the two models were applied on El-Salam Canal considering three scenarios to identify the safety factors including the effect of sea level rise (SLR), earthquake acceleration and a combination of the two scenarios. The results indicated that dynamic response values of the canal slope have different variation rules under near and far field earthquakes. Finally, the damage location and pattern of the slope failure are different in varying groundwater conditions.

The water shortage issue may put a spotlight over most of the Middle East region and push many nations to re-planning the water resources in various respects. Providing data on water’s economic value assists policymakers make informed decisions regarding water distribution. Additionally, addressing the increasing demand for all uses and building the sustainable future of agricultural and water policies. The purpose of this article is to explore and evaluate the economic value of irrigation water in Sharkia Governorate, regarded one of Egypt’s largest provinces. It also examines how to maximize the economic value of irrigation water, taking into account the self-sufficiency of main crops. Furthermore, consideration has been given to the political demands for the allocation, management and control of water resources. The simulation software Operational, Planning and Distribution Model (OPDM) was used to simulate through the studied province the accessible water distribution and crop yield. Moreover, it is used to judge the impact of irrigation water utilization and to check gross income. Furthermore, from a technical and economic point of perspective, the distinct suggestions were contrasted. The research evaluates the present crop pattern for wheat and cotton attaining a peak economic value of 1.23 EGP/m3 and 0.98 EGP/m3 of irrigation water for wheat and cotton respectively. Moreover, it reaches 0.41 EGP/m3 for rice which considered one of the highest plants in water consumption. Finally, these findings may highlight some strategic crops future development.

Wetlands in Louisiana’s Chenier Plain are undergoing persistent deterioration that will become increasingly problematic if not adequately addressed. Many projects are proposed with the goal of protecting or restoring the wetlands. One such type of projects is freshwater introduction, aims to decrease the salinity levels in a marsh. The project is located in the Mermentau Basin in southeastern Vermilion Parish, Louisiana. The study allows freshwater to drain into the Chenier subbasin, while reducing the effects of excess water in the Lakes subbasin. The area is studied using the aerial view geographic information systems (GIS) map alongside with the aerial photos and LiDAR images of canals located near Pecan Island. Moreover, the general mass-balance formulas for both water level and salinity are derived.

Lafayette consolidated government purchased “Horse Farm”, therefore plans are undergoing to develop it into a city park. The developments proposed to the city park have implications for the hydrologic and hydraulic conditions of the main channel that runs through the park, Coulee Mine, and its overall watershed. The proposed master plan is suggesting two main changes: (1) Converting the concrete coulee into natural coulee and, (2) Adding natural lakes to the right bank of the coulee. This paper is focusing on investigating the effects of the proposed project on the entire watershed. The investigations are conducted using numerical modelling techniques; namely the HEC-HMS and HEC-RAS models. Finally, the changes in water surface profiles, flow hydrographs across the Coulee Mine channel and storage of the natural lakes added are investigated.

Dams and reservoirs located near populated areas represent a potential risk in the event of uncontrolled release of the reservoir water due to earthquake damage, endangering the people and properties.In the present work, the seismic performance of concrete gravity dams is studied numerically using commercially Finite Element based software ADINA (Automatic Dynamic Incremental Nonlinear Analysis).The study gives deep insight into the procedure of analysis and safety evaluation of concrete gravity dams, as well as improving its stability under earthquake loading.In the present study, the horizontal component of North Ridge earthquake was selected for analysis.The study covers a range of parameters including the effect of earthquake horizontal acceleration component, substrate soil type and strength properties of soil on the stability of concrete gravity dams.The behavior of upstream water surface under seismic shaking was also considered in the research.The results indicated that the relative uplift force, Ur, is linearly proportion to earthquake intensity.On contrary, Ur, decreases as the relative height of water in the reservoir, Hw/H, increases.The factors of safety, F.S, against overturning and sliding decrease with increasing the earthquake intensity.It was also found that sliding was the governing factor against failure.

A number of embankment dams have failed or suffered major deformations during earthquakes.Numerical modeling methods can provide a powerful tool to predict the response of dams to earthquake loading.In the present work, the seismic performance of rockfill dams is numerically studied using the software ADINA (Automatic Dynamic Incremental Nonlinear Analysis) based on finite element method.The study is carried out to investigate the analysis procedures and safety evaluation of rockfill dams, and to improve its stability under earthquake loading.The study also investigates the generation and dissipation of pore water pressure generated within the dam clay core, the effect of earthquake horizontal acceleration component, and upstream water level on the stability of rockfill dams.Results indicated that large deformations took place within the clay core of the rockfill dam that consequently caused large crest settlements accompanied by relatively high generation of pore water pressure within that core.Moreover, the crest vertical displacements which can be used as an index of dam stability were relatively large enough in some cases to be more than freeboard that leads to overtopping.

This paper illustrates the assessment between the multiloop control strategies that aim to damp the resonance hazard of LCL-filters and expanding the available stability margins. The establishment of the multiloop control is sustained in a sensorless manner with the reconstruction of the state variables using the Kalman observer, thus enhancing the cost measures and reliability of the distributed generation (DG) interface. Compared to the conventional multiloop techniques, which is mainly based on the feedback of either the filter capacitor current or voltage, the proposed multiloop method is able to exhibit: 1) theoretical stability through the whole frequency spectrum; 2) higher disturbance rejection originating from the grid-side interference; 3) higher damping of the dominant poles with much lower control effort than the conventional methods; 4) straightforward tuning of the grid current controller as the LCL-filter appears as an apparent standard second order model; and 5) low sensitivity against parameter deviations compared to previous literatures. Furthermore, the utilized control scheme ensures a high quality of injected grid currents under unbalanced and distorted grid voltage conditions. Experimental results validated the proposed control concept through a 3.5 kW setup.

Due to the large variety of renewable power sources, power electronics play an important role in energy conversion. Different power converter topologies are used to interface distributed power generation systems (DPGS) with the utility network. Introduction of power electronics for DPGS provide several advantages such as energy optimal operation by employing a control algorithm to extract the maximum available power. In addition, load control, reduced noise, controllable active and reactive power and improved power quality. These achievements are further improved by digital control systems. The analysis presented in this paper shows the relations of how the stability margins and the transient response criteria are related to the sampling frequency, computational delay and controller gains. The procedure followed can be applied to any filter order with any number of samples of control delay at any sampling frequency. This gives a straightforward method for optimal tuning of the stationary frame AC current controllers with the required stability margins and transient response characteristics. The concluded assumptions were simulated & verified through Matlab/Simulink.

One of the main issues accompanied with the high penetration of PV distributed generation (DG) systems in low voltage (LV) networks is the overvoltage challenge. The amount of injected power to the grid is directly related to the voltage at the point of common coupling (PCC), which necessitates limiting the amount of injected power to the grid to conservative values compared to the available capacity from the PV panels particularly at light loading. In order to mitigate the tradeoff between injecting the maximum amount of electrical power and voltage rise phenomena, many control schemes were suggested in order to optimize the operation of PV DG energy sources as well as maintaining safe voltage levels. Unlike these conventional methods, this paper proposes a combined PV inverter-based distributed generation and flywheel energy storage system to ensure improved voltage regulation as well as making use of the maximum available power from the PV source at any instant, decoupling its relation with the terminal voltage. The concluded assumptions were simulated through Matlab/Simulink and verified experimentally.

The control of power electronic converters is subjected to several challenges as measurement sensors drift, malfunction in harsh environments, non-ideal grid, and performance degradation due to the delay of discrete control systems. In this paper, a stationary frame resonant current controller for inverter-based distributed generation (IBDG) with sensor-less grid voltage operation is proposed. The delay sources are taken into account and compensated. The proposed approach is simulated through Matlab/Simulink and verified experimentally.

Due to the large variety of renewable power sources, power electronics play an important role in energy conversion. Different power converter topologies are used to interface distributed power generation systems (DPGS) with the utility network. Introduction of power electronics for DPGS provide several advantages such as energy optimal operation by employing a control algorithm to extract the maximum available power. In addition, load control, reduced noise, controllable active and reactive power and improved power quality. Using a LCL filter to ensure that high quality power is delivered comes at the expense of degraded stability unless mitigation procedures are followed. In this paper, a stationary frame current control for inverter-based distributed generation (IBDG) with sensorless active damped LCL filter is proposed. The Kalman filter sensorless-based technique not only mitigates the stability problem regarding the resonance of the LCL filter, but it improves the overall stability margins. The concluded assumptions were simulated through Matlab/Simulink and verified experimentally with a laboratory prototype.

Due to the rapid growth of the electric energy demands, the necessity of involvement of distributed generation (DG) to overcome this demand became a must. When distributed generation renewable energy sources are coupled to the grid through a DC-AC inverter, the injected currents to the grid should be characterized by high quality and low distortion. Many factors play an important role to produce high quality output beginning with the order of the passive filter used, type of controller used and last but not least the presence of distortions in the grid. This paper demonstrates the evaluation of performance, in normal and abnormal grid conditions, between single and dual loop control for the three phase inverter tied to the grid through a LCL passive filter and controlled with discrete proportional resonant (PR) controller, taking into account how filter parameters, control gains and sampling frequency would affect the dynamics of the system as well as its stability in order to perform adequate tuning. The concluded assumptions were simulated & verified through Matlab/Simulink.