Sameh Ahmed Kantoush

Kyoto University | Kyodai · Disaster Prevention Research Institute

The impacts of Flood Retention Dams (FRDs), designed solely for flood control and featuring bottom outlets at the riverbed level, on benthic invertebrate communities have not been sufficiently elucidated. This study investigated the impact of FRDs on benthic invertebrate communities downstream and reservoirs, focusing on differences in riverbed con...

Sediment Bypass Tunnels (SBTs) effectively mitigate reservoir sedimentation by diverting flood-laden flows, but they face significant challenges due to hydroabrasive erosion, which compromises their sustainability. Predicting this abrasion is complex due to the intricate interactions between flow hydraulics and sediment transport, along with limite...

In rapidly urbanizing regions, the proliferation of plastic debris in sedimentary environments poses multifaceted challenges, particularly in vulnerable urban slum areas where the deplorable state of waste management has led to considerable littering and dumping. In association with the general absence of adequate drainage systems, and appalling sl...

In semi-arid climates, precipitation is the most important hydrometeorological event since it remains the main source of water. In the context of climate change, the analysis of its temporal trends provides useful information for effective planning and management of water resources. Daily rainfall data collected from 12 meteorological stations in t...

The coastal zones worldwide are densely populated and, as a result, are among the areas most affected by urbanization. However, coastlines are very dynamic and always changing due to a variety of human and natural factors. One of today's most concerning coastal risks is erosion, which can seriously harm buildings and infrastructure along the coast....

Sharp-crested weirs are commonly used in hydraulic engineering for flow measurement and control. Despite extensive research on sharp-crested weirs, particularly regarding their discharge coefficients, more information is needed via research on their energy dissipation downstream. This study conducted experimental tests to assess the influence of co...

The Madjez Ressoul watershed, located in Algeria (A = 103 km2), provides a unique opportunity to investigate the accurate prediction of flood hydrographs in a natural setting and relatively untouched environment. Its particularity is an excellent option for simplified rainfall–runoff models due to the potential reduction in model complexity and dat...

Understanding changes in rainfall patterns is vital for effective water resource management and agricultural planning in climate-sensitive regions. In Northeastern South Kivu, Democratic Republic of the Congo, limited knowledge of rainfall dynamics poses challenges for local climate assessments. This study analyzed rainfall patterns using the Cli...

Urbanization in major cities has resulted in increasing urban slum expansion. This, together with increased climate-change-driven hazards, and deplorable slum characteristics has led to consid erably higher flood impacts in slum settlements. As such, there is a need for specialized flood vulnerability assessment tools that integrate features specif...

Reservoir sedimentation is a critical issue that impacts dam operations by reducing storage capacity and increasing management costs. This study evaluated the effectiveness of memetic programming (MP) in predicting the suspended sediment concentration (SSC) in the Miwa Reservoir, Japan. The Miwa Dam faces challenges due to its high sediment yield a...

This study investigates the impact of climate change on hydrological dynamics in the Ruzizi River Basin (RRB) by leveraging a combination of observational historical data and downscaled climate model outputs. The primary objective is to evaluate changes in precipitation, temperature, and water balance components under different climate scenarios. W...

Soil erosion is considered one of the most prevalent natural hazards in semiarid regions, leading to the instability of ecosystems and human life. The main purpose of this research was to investigate and analyze soil erosion susceptibility maps in the Medjerda basin in northern Africa. This study utilizes four ensemble models based on the analytica...

Future changes in streamflow and sediment, influenced by anthropogenic activities and climate change, have a crucial role in watershed management. This study aimed to quantify the effects of anthropogenic and natural drivers on future streamflow and sediment changes in the tropical Sai Gon Dong Nai River basin using the Soil and Water Assessment To...

The re-evaluation of the traditional river training structure "Seigyu" in the Kizu River, Japan, highlights its impact on flow dynamics and sediment transport. Seigyu, a nature-based solution, has shown diverse flow patterns, reduced flow velocity, and promoted geomorphological changes. The transformation of Seigyu, including debris trapping and in...

Despite their popularity, the construction and operation of hydropower reservoirs pose challenges to water resources. This study investigated the impacts of cascading dams on streamflow in Tanzania’s Rufiji River Basin. The SWAT model was developed to represent the entire Rufiji River Basin. The model simulated the streamflow for 41 years, from 198...

Field measurement of the bed roughness of tropical tidal rivers is a long and expensive process. In this study, we quantified the roughness coefficient from the acoustic Doppler current profiler (ADCP) measurements considering flow characteristics along a 240 km length of the Vu Gia Thu Bon River system, in central Vietnam. Our approach entailed th...

In the Mekong Basin, rice plants have low yields because of degraded soils, fresh water is becoming scarce, and rice cultivation consumes a lot of water. Beijing-directed rules to govern the river and its plan to build cascade dams upstream have weakened the Mekong River. The Mekong River Commission was established in 1957, but for over 50 years, t...

The problem of flooding in Central Vietnam in general and the lower Ba River in particular is one of the natural disasters that frequently threatens people's lives and socioeconomic development in the region. Especially, climate change is becoming ever more prominent and hotter, making extreme natural disasters more unusual and unpredictable. In th...

The presence of a wastewater treatment plant in the Arab El-Madabegh region, which discharges excessive amounts of raw effluent toward the nearby farming fields, is the area’s main issue. Examining the harmful implications of raw effluent releases on groundwater quality, determining if treated wastewater effluent complies with regulations for disch...

The contagious COVID-19 has recently emerged and evolved into a world-threatening pandemic outbreak. After pursuing rigorous prophylactic measures two years ago, most activities globally reopened despite the emergence of lethal genetic strains. In this context, assessing and mapping activity characteristics-based hot spot regions facilitating infec...

Human interventions at the river basin scale, such as sand mining and hydropower dam construction, have profoundly affected hydrological and hydraulic alteration regimes, sediment budgets, and morphological changes worldwide. Quantifying the consequences of unsustainable ongoing sand mining and hydropower is crucial for obtaining sediment load data...

The Vu Gia Thu Bon River (VGTB) basin is an important watershed, serving as a primary source of drinking water and supporting agricultural production in Central Vietnam. However, the potential hydrological responses of anthropogenic activities, such as land use/land cover (LULC) change and dam development, have not been comprehensively quantified i...

Rapid urbanization has dramatically increased the demand for river sand, leading to soaring sand extraction rates that often exceed natural replenishment in many rivers globally. However, our understanding of the geomorphic and social-ecological impacts arising from Sand Mining (SM) remains limited, primarily due to insufficient data on sand extrac...

Quantifying the extent of drought and flood magnitude and frequency under the climate change impacts is essential for effective water resource management. In this study, we utilize the Soil and Water Assessment Tool (SWAT) hydrological model, drought indices, and the Interquartile Range (IQR) method for a comprehensive analysis of the river flow re...

Extreme weather threatens livelihood and urban development in the Philippines. However, addressing their effects and occurrences is a significant challenge, particularly in the Cagayan River Basin (CRB), due to increasing population and the dilemma of dam operations for floods and droughts management. Therefore, this paper focuses on investigating...

Rapid urbanization has dramatically increased the demand for river sand, leading to soaring sand extraction rates that often exceed natural replenishment in many rivers globally. However, our understanding of the geomorphic and social-ecological impacts arising from Sand Mining (SM) remains limited, primarily due to insufficient data on sand extrac...

Human interventions activities around the world, particularly reservoir operation, have dramatically altered hydrological and sediment regimes in most of the major river basins. In the Mekong River, specifically the Upper Srepok River Basin (USRB) which is a main tributary of the river basin connected to the Mekong Delta's rice bowl and the Tonle S...

Predicting flash flood-prone areas is essential for proactive disaster management. ‎However, such predictions are challenging to obtain accurately with physical hydrological models owing to the scarcity of flood observation stations and the lack of monitoring systems. This study aims ‎to compare machine learning (ML) models (Random Forest, ‎Light,...

Urban sewer system management is challenging due to its higher vulnerability to flooding caused by rapid urbanization and climate change. For local decision-makers, storm water management is essential for urban planning and development. Therefore, the main objective of this study is to develop a numerical model for the sewerage network of the centr...

Siltation significantly threatens a reservoir’s original storage capacity and lifespan. Pressure flushing is an effective measure against siltation through the partial drawdown of the reservoir water level with limited flushed cone volumes in front of the bottom outlet. In this study, a novel configuration with submerged vanes has been proposed and...

The Vietnamese Mekong Delta (VMD) plays an extremely important and central role in the country's food security. The influences of the upstream dam's development, sea-level rise, and complicated tidal regime in the dry season have caused barriers and constraints for local agricultural activities in VMD. Once these causes combined climate change, the...

Point predictions of hydroclimatic processes through nonlinear modeling tools are associated with uncertainty. The main goal of this research was to construct prediction intervals (PIs) for nonlinear artificial neural network (ANN)-based models of evaporation and the standardized precipitation index (SPI). These are two critical indicators for clim...

This study investigated the uncertainty involved in statistical downscaling of hydroclimatic time series obtained by artificial neural networks (ANNs). Phase 6 of the Coupled Model Intercomparison Project (CMIP6) general circulation model (GCM) Canadian Earth System Model, version 5 (CanESM5), was used as large-scale predictor data for downscaling...

Cities have experienced rapid urbanization-induced harsh climatic events, especially flooding, inevitably resulting in negative and irreversible consequences for urban resilience and endangering residents' lives. Numerous studies have analyzed the effects of anthropogenic practices (land use changes and urbanization) on flood forecasting. However,...

Cities have experienced rapid urbanization-induced harsh climatic events, especially flooding, inevitably resulting in negative and irreversible consequences for urban resilience and endangering residents' lives. Numerous studies have analyzed the effects of anthropogenic practices (land use changes and urbanization) on flood forecasting. However,...

This study aims to examine three machine learning (ML) techniques, namely random forest (RF), LightGBM, and CatBoost for flooding susceptibility maps (FSMs) in the Vietnamese Vu Gia-Thu Bon (VGTB). The results of ML are compared with those of the rainfall-runoff model, and different training dataset sizes are utilized in the performance assessment....

Understanding the dynamics of flooding events is crucial to mitigate flood risks, particularly in developing nations like Sudan. This study combines multi-sensor approaches with Rainfall-Runoff-Inundation (RRI) modeling to predict flood inundation extent over the Nile River Basin (NRB). Building upon the RRI model, we firstly simulated the streamfl...

Hydraulic infrastructures, such as reservoirs and water diversion channels, cause altered streamflow worldwide. Therefore, this study aimed to assess the coupled impacts of reservoir operations and water transfer on downstream streamflow over 42 years (1979–2020) for a tropical river in Vietnam, the Vu Gia Thu Bon (VGTB). We also quantified variati...

Sediment depletion in the Vietnamese Mekong Delta (VMD) has brought threats to riverbed and riverbank dynamics. The main objective of this research is to make a relationship between turbidity and suspended sediment concentration (SSCs) and to assess temporal-spatial variations of SSCs in the VMD. In this regard, the SSCs were measured and monitored...

Several cities are exceptionally vulnerable to flood impacts due to increasing urbanization, population growth, and climate change. Quantifying flood vulnerability is useful for identifying the system's weakness, monitoring its evolution, and supporting targeted flood risk adaptation policies. One of the vital aims of assessing urban flood vulnerab...

The concepts notes were developed to facilitate discussion among various stakeholders gathered from around the world to share information on their ongoing research activities and current research projects, find collaborative activity partners, showcase research achievements, and challenge further improvements to disaster risk reduction and resilien...

Soil erosion, sediment yield, and sediment transport associated with flash flooding in arid regions result in reservoir storage losses, decreased infiltration, high evaporation rates, and degradation of downstream channels. However, the lack of observational data from wadi systems and an empirical formula to compute sediment yield has hindered rese...

The Vu Gia Thu Bon basin constitutes the primary water supply in Central Vietnam. While climate change disturbs stream discharges and affects flood extremes, upstream dam development may intensify or mitigate such impacts. Therefore, this study provides a quantitative evaluation of long-term alterations in the flow regimes of the VGTB rivers from 1...

Siltation is a major threat to the original storage capacity and lifespan of a reservoir. Pressure flushing is an effective measure against siltation through the partial drawdown of the reservoir water level with limited flushed cone volumes in front of the bottom outlet. In this study, a novel configuration with submerged vanes has been proposed a...

Understanding the complexity of the siltation process and sediment resuspension in shallow reservoirs is vital for maintaining the reservoir functionality and implementing sustainable sediment management strategies. The geometry of reservoirs plays an indispensable role in the appearance of various flow structures inside the basin and, consequently...

Flow, suspended sediment transport and associated morphological changes in the Vietnamese Mekong Delta (VMD) are studied using field survey data and a two-dimensional (2D) depth-averaged hydromorphodynamic numerical model. The results show that approximately 61–81 % of the suspended sediment load in the Hau River during the flood seasons is diverte...

Sedimentation in front of a dam is the main obstacle against reservoir sustainability. Due to the limited availability of suitable new dam sites, the ramifications of inefficient sediment management are associated with socio-economic concerns and environmental issues. Most of the existing sediment management techniques are unfavorable for arid and...

Increasing flood risk due to rapid urbanization and climate change calls for improved integration between flood risk management and spatial planning processes to enhance the resilience of cities, including in Egypt. Although much work has been conducted on flood impact in Egypt, the gap in integrating flood risk assessment with spatial planning pra...

Flood risk mapping forms the basis for disaster risk management and the associated decision-making systems. This process' effectiveness depends on the quality of the input data of both hazard and vulnerability maps and the method utilized. Worldwide, although there are thousands of studies in Flood Vulnerability Assessment (FVA), however, compariso...

Because recurring floods in the Philippines have become more damaging throughout time, risk assessments, quantifying, and visualizing flood damages as accurately as possible become imperative. To deal with an up-to-date database and a practical assessment tool, a satellite imagery-based method was used which aimed to map flood inundation and estima...

Severe flash floods have hit Jordan in recent years, e.g., in 2018 and 2020, leading to fatalities and infrastructure damages. Moreover, even though Jordan is one of the water scarcest countries of the world, extreme rainfall events might occur more frequently under climate change (IPCC Sixth Assessment Report 2021), causing flash floods in wadi sy...

Medjerda is a key transboundary watershed (Algeria and Tunisia) in the Maghreb region. The analysis of rainfall regime in this basin is of paramount importance for water resources management and for regional economic development notably in relation with agriculture. This study examines the rainfall trends over the Medjerda watershed on a multi-temp...