Hasil untuk "River protective works. Regulation. Flood control"

Yue Guo, Jianzhu Li, Hang Zeng et al.

ABSTRACT With global climate change and human activities, environmental uncertainties are increasing, and extreme flood events are occurring more frequently. The reliability of traditional hydrological frequency analysis theories, based on the assumption of stationarity, is being increasingly questioned. This study aims to develop a non‐stationary flood frequency analysis model using the Generalized Additive Models for Location, Scale, and Shape (GAMLSS) framework, with time and climate indices as covariates. The model calculation and frequency analysis are conducted using 2000 years of climate indices reconstructed by the Paleo Hydrodynamics Data Assimilation product (PHYDA). Design floods for different return periods are then quantified based on the reconstructed data. The results show that the nonstationary model established with climate indices as covariates can accurately identify the trend of first decreasing and then increasing flood series at the FP and ZJG stations in the Daqing River Basin, achieving the best model performance. Moreover, using the PHYDA‐reconstructed climate indices from the past 2000 years to extrapolate floods and calculate design floods provides higher safety for certain return periods than observed series. However, under longer return periods, the design values are smaller than those of the existing observed series. Overall, the nonstationary model proposed in this study can serve as a tool for flood frequency analysis under climate change. Additionally, incorporating the climate indices from the past 2000 years into nonstationary flood frequency analysis provides design results that can offer valuable references for regional water infrastructure design.

Zeyad Ayoob Sulaiman, Mena Ahmed Al Sawaf, Ahmed Shareef Hayder et al.

Many fluvial systems have undergone significant changes in their morphology due to base level fall since the last glaciation. Channels in such transient fluvial systems continuously adjust their morphology and may still be incising until reaching a new equilibrium condition. This study examines morphometric change detection indices and techniques to quantify and analyze the recent variations in the channel properties of the lower portions of the Le Sueur and Maple Rivers, in response to upstream knickpoint migration. The results reveal that channel reaches upstream of the knickzones remain relatively stable, exhibiting low channel bed gradients and minimal morphological change. In contrast, the local channel gradient increases about ∼3 fold near the knickpoints and continues with predominantly high rates into the downstream direction. Together, the morphometric indices indicate that the channel geometry of the Maple and Le Sueur Rivers downstream of the knickpoints is actively adjusting to accommodate the rapid base level drop. Because of incomplete adjustment processes, both rivers experienced remarkable change in channel geometry between 2008 and 2015, albeit with differing adjustment patterns. In particular, the percentage change in channel properties along the knickzone reaches up to 120% for the channel cross-sectional area, 60% for the channel width, and 75% for the mean hydraulic depth. These changes are accompanied by a sharp increase in cross-sectional stream power and impose boundary shear stress along the knickzones which amplify sediment transport capacity and drive further modifications to channel size and shape. This study provides a quantitative framework for assessing geomorphic responses to base level drop and provides insights into the feedback mechanisms between hydraulic forces and channel morphology. The findings have broader implications for understanding channel evolution under non-equilibrium conditions and for guiding river management in similar fluvial systems.

Matteo Rillo Migliorini Giovannini, Giuseppe Francesco Cesare Lama, Lorenzo Scopetani et al.

ABSTRACT In the last few years, vegetated rivers have been managed with the main purpose of achieving water drainage and improving conveyance through vegetation removal. However, this leads to peak discharge augmentation and wave travel time reduction. This study assesses vegetation shredding and selective cut impacts on flood risk management. Flow resistance was obtained considering vegetation morphology and hydrodynamic measurements performed during two field campaigns conducted just before the destructive cut and in the growing season after 4 years. Järvelä model was adopted by modeling shrubby vegetation Leaf Area Index (LAI), while Nepf model was selected for herbaceous vegetation, based on flexible plants reconfiguration, strongly dependent on vegetation species and type. Finally, Baptist et al. model was employed for woody rigid plants, modeled as a random or staggered array of rigid cylinders. Results of one‐dimensional unsteady hydraulic numerical simulations show higher water levels 4 years after the severe cut, while selective thinning reduces them. This methodology allows the quantification of flood propagation and peak flow delay: wave celerity decreases up to 21% and up to 34% (for undisturbed vegetation and clear cut scenarios, respectively) because of vegetation re‐growth, causing a flood delay from 20 to 30 min at the downstream cross‐section.

Adam Griffin, Gianni Vesuviano, Donna Wilson et al.

ABSTRACT England experienced a sequence of extreme flood events between June 2019 and April 2021. To understand the severity and likelihood of the events, a set of over 300 flow and river level stations was investigated for key events (identified by Environment Agency Area Teams), focusing on frequency analysis of peak flow, peak level and cumulative flow volume. In addition, groundwater, soil moisture and seasonal total rainfall were analysed to understand the antecedent conditions affecting the impacts of the rainfall experienced. While the period contained some of the wettest months on record, there were few extreme short‐duration rainfall events. Record‐breaking flows and river levels were seen across the country, in part due to the extreme antecedent conditions where many parts of England had record groundwater levels and soil moisture content preceding the events. A kernel density approach was used to identify statistically significant clusters of events over the study period (compared with a Poisson process) and found that most stations in northern and western England experienced a cluster during the study period. Urbanisation was investigated as a possible driver of these trends, but urban increase was not seen to be a significant driver.

Vincent Canwat

Abstract Early warning systems play significant roles in disaster risk reduction and management. However, a global picture of how they function on the ground, especially in developing countries, is lacking. This study assessed social innovations and drivers in the community‐based transboundary flood early warning systems in the Ugandan context. The study found that the community‐based transboundary flood early warning system generated three social innovations: new inter‐community relations, new community‐local resource relations, and new housing and bedding structures. New inter‐community relations were driven by the transboundary nature of the flood and kinship. New community‐local resource relations were driven by the lack of government support for the early warning system. New housing and bedding structures were driven by the uncertainty about the flood at night. The study confirms the importance of social market failure in driving social innovations and the role of community‐based flood early warning systems in promoting the utilisation of local resources. The effectiveness of transboundary early warning systems in extending lead time and reducing losses was also confirmed. However, the early warning system was found to be effective only during day time. The study, therefore, recommends government intervention in bridging the early warning system gap by installing telemetry.

Funmilayo Ebun Rotimi, Roohollah Kalatehjari, Taofeeq Durojaye Moshood et al.

ABSTRACT The discourse on climate change has brought to the fore the pressing need for improved flood management strategies. Recent trends indicate a surge in flooding incidents in residential areas, which can potentially disrupt socio‐economic activities and result in loss of lives. This study conducts a Systematic Literature Review (SLR) to comprehensively assess and compare various flood mitigation strategies employed in residential zoning practices globally. Residential zoning in New Zealand means a designated area of land specifically set aside for housing development, with rules and regulations governing the density and type of dwellings that can be built there to maintain a suitable living environment for residents. Research articles published between 2001 and 2024 focused on flood reduction strategies were collected, synthesised, and analysed. A predefined review protocol guided this approach, involving searches in widely used electronic databases. Ninety‐three articles were ultimately included in the review. The findings highlight several key areas, including the impact of strategies on flood susceptibility, the effectiveness of rainwater harvesting systems and green infrastructure in flood management, and the importance of sustainable urban development and ecological preservation. Proposed strategies, such as neighbourhood and site planning, regional planning, stormwater management, green roofs, permeable pavements, and regulatory measures, offer valuable pathways for safeguarding water resources in urban planning efforts. The study advances knowledge in urban planning, environmental sustainability, and residential zoning practices. It also provides an overview of current approaches for mitigating flooding and identifies research gaps for future studies.

Mahmoud M. Afify, Ismail Abd‐Elaty, Amir S. Ibrahim et al.

ABSTRACT Flooding is a natural calamity that causes widespread devastation, including severe infrastructure destruction, significant economic consequences, and social disturbances around the world, particularly in the Sinai region. Wadi Ked is one of Sinai, Egypt's, most vulnerable districts to flood hazards, and it is the location used for this study. This study aims to create a map of flood‐prone areas in Wadi Ked by combining Geographic Information System (GIS) technology and multi‐criteria decision‐making (MCDM) techniques, utilizing the Analytical Hierarchy Process (AHP) methodology. To achieve the study's goal, flood‐related factors such as elevation, slope, distance to roads, distance from streams, annual rainfall, drainage density, topographic wetness index, land use and land cover, normalized difference vegetation index, soil type, and curvature were weighted and overlaid. The results show that 26.91% of the areas studied have a low sensitivity to flooding, whereas roughly 73.09% of the area is moderately to very highly vulnerable to flooding. The study proposed a dam with a height of 30 m, a width of 0.416 km, and a lake capacity of 31.74 million cubic meters (MCM). The surface runoff volumes from 50‐ and 100‐year storms in sub‐basins 1–5 are 23.07 MCM and 29.66 MCM, respectively. Model validation was performed by comparing susceptibility maps generated from literature‐based and expert‐based AHP weights, revealing a 98% spatial agreement and a Kappa coefficient of 0.995, confirming the model's robustness. This study offers value to decision‐makers and planners by utilizing morphometric properties and flash flood risk maps to identify suitable locations for dams.

Cheng‐Wei Yu, Wun‐Jhen Yang, Dongyu Feng

ABSTRACT The conventional approach to generating synthetic rating curves (SRC) using the Height‐Above‐the‐Nearest‐Drainage (HAND) method typically relies on the assumption of uniform flow, such as Manning's equation, to establish stage‐discharge ratings. The zero‐physics application of the uniform flow equation is insufficient for capturing detailed hydraulic features (e.g., backwater effect) and neglects the hydraulic effects from adjacent channels. This lack of hydrodynamic computation can impact the accuracy and effectiveness of riverine flood risk estimation and management. To reduce this foreseeable error, we introduce the HAND‐hd workflow, which integrates sophisticated hydrodynamic computations in the production of HAND‐based SRC with hydrodynamic features (SRChd). The results indicate that SRChd demonstrates consistent agreement with both gauge observations and benchmark solutions. Additionally, the comparative analysis suggests that SRChd provides notable improvements in stage‐discharge ratings over conventional HAND‐based SRCs, particularly in channels with mild bed gradients, where it reduces water stage prediction errors and percent biases. In steeper channel segments, SRChd maintains comparable accuracy to conventional methods. The comprehensive evaluation in this study emphasizes the potential discrepancies and inaccuracies associated with the adoption of the uniform flow assumption in the conventional HAND‐SRCs and addresses the necessity of including hydrodynamic physics in the application of HAND‐based SRC (e.g., inundation map) in channels with mild gradients.

James Dallas, John Talbot, Makoto Suminaka et al.

This manuscript presents a control barrier function based approach to shared control for preventing a vehicle from entering the part of the state space where it is unrecoverable. The maximal phase recoverable ellipse is presented as a safe set in the sideslip angle--yaw rate phase plane where the vehicle's state can be maintained. An exponential control barrier function is then defined on the maximal phase recoverable ellipse to promote safety. Simulations demonstrate that this approach enables safe drifting, that is, driving at the handling limit without spinning out. Results are then validated for shared control drifting with an experimental vehicle in a closed course. The results show the ability of this shared control formulation to maintain the vehicle's state within a safe domain in a computationally efficient manner, even in extreme drifting maneuvers.

Robin Strässer, Karl Worthmann, Igor Mezić et al.

Controlling nonlinear dynamical systems remains a central challenge in a wide range of applications, particularly when accurate first-principle models are unavailable. Data-driven approaches offer a promising alternative by designing controllers directly from observed trajectories. A wide range of data-driven methods relies on the Koopman-operator framework that enables linear representations of nonlinear dynamics via lifting into higher-dimensional observable spaces. Finite-dimensional approximations, such as extended dynamic mode decomposition (EDMD) and its controlled variants, make prediction and feedback control tractable but introduce approximation errors that must be accounted for to provide rigorous closed-loop guarantees. This survey provides a systematic overview of Koopman-based control, emphasizing the connection between data-driven surrogate models, approximation errors, controller design, and closed-loop guarantees. We review theoretical foundations, error bounds, and both linear and bilinear EDMD-based control schemes, highlighting robust strategies that ensure stability and performance. Finally, we discuss open challenges and future directions at the interface of operator theory, approximation theory, and nonlinear control.

Luis Fernando Nazari, E. Camponogara, L. O. Seman

The impacts incurred by floods regularly affect the planet's population, inflicting social and economic problems. Optimal control strategies based on reservoir management may aid in controlling floods and mitigating the resulting damage. To this end, an accurate dynamic representation of water systems is needed. In practice, flood control strategies rely on hydrological forecasting models obtained from conceptual or data-driven methods. Encouraged by recent works, this research proposes a novel surrogate model for water flow in a river channel based on physics-informed neural networks (PINNs). This approach achieved promising results regarding the assimilation of real-data measurements and the parameter identification of differential equations that govern the underlying dynamics. This article investigates PINN performance in a simulated environment built directly from a configuration of the Saint-Venant equations. The objective is to create a suitable model with high prediction accuracy and scientifically consistent behavior for use in real-time applications. The experiments revealed promising results for hydrological modeling and presented alternatives to solve the main challenges found in conventional methods while assisting in synthesizing real-world representations.

Eleni Tzanou, Charalampos Skoulikaris

This research aims to evaluate the operational effectiveness of current flood protection infrastructure and measures in a flood-prone area using geo-referenced information systems and SWOT analysis. To achieve this, all existing flood protection measures and works in the case study basin, namely Strymonas River basin in Greece, were mapped and recorded. These data, along with water-related spatial information, were stored in a geo-referenced database created within an open-source GIS environment. Additionally, the system was populated with the basin’s recorded historic floods, derived from the European Union’s Floods Directive implementation process. The outputs of the research, which include a spatial comparison of flood protection measures and works with flood event occurrences as well as analyses of the figures, density, and locations of flood protection works, were evaluated as an integrated system and further processed using SWOT analysis. The latter was informed by questionnaire results, and the identified strengths and weaknesses of the flood protection infrastructure were used to explore potential opportunities and threats, which could respectively reinforce or jeopardize the basin’s capacity to effectively respond to future floods. The research framework can be applied to any river basin and could provide important assets in flood protection planning at a basin scale.

Shasha Zhang, Shuli Xue, Huimin Jian et al.

David Archer, Samuel Watkiss, Sarah Warren et al.

Abstract Extremely rapid rates of rise in level and discharge in a subset of flash floods (‘abrupt wave front floods’, AWF) are separate hazards from peak level. Such flood events are investigated for Pennine catchments in northern England using both gauged and historical information. Gauged level and flow digital records at 15‐min intervals provide recent data. Historical information for 122 AWF events is extracted from a chronology of flash floods for Britain. Historical AWF events are mapped and found to occur on every major Pennine catchment; catchment descriptors are derived as a basis for assessing catchment vulnerability. We discuss the disputed origin of AWF. Using gauged data, we contrast the rising limb of AWF and ‘normal’ floods. We investigate time series of historical AWF, noting a puzzling peak in the late 19th century. Current rainfall and river monitoring does not provide a reliable basis for understanding AWF processes or for operational response and we suggest improvements. Similarly, current models for design flood estimation and forecasting do not generate the observed rapid increase in level in AWF floods.

علیجان آبکار, حمزه سعیدیان

مقدمه استفاده از مردم، در اجرای طرح‌های منابع طبیعی، موفقیت این طرح‌ها را تضمین می‌کند و می‌تواند برای منابع طبیعی موجود در حوزه‌های آبخیز و ذی‌نفعان بسیار مفید باشد. مشارکت مردمی در اجرای عملیات منابع طبیعی ازجمله رویکردهای ضامن تحقق اهداف و موفقیت این طرح‌ها است. توجه به مشارکت مردمی در حفاظت از منابع طبیعی از اهمیت و اعتبار بالای برخوردار است، البته منابع طبیعی، به‌عنوان یکی از ارکان جدایی‌ناپذیر زندگی انسان‌ها نیز به شما می‌رود. طرح‌های منابع طبیعی برای بهبود شرایط محیطی و اجتماعی سامانه‌های اجتماعی-بوم‌شناختی برنامه‌‌ریزی و اجرا می‌شوند. بنابراین، با توجه به اینکه این پژوهش در حوزه‌های آبخیز کویری است و شرایط این حوزه‌ها خاص و منحصربه‌فرد است، بنابراین، این شرایط از ویژگی‌های ممتاز این پژوهش نیز محسوب می‌شود و می‌تواند ارزش و اهمیت وضعیت تشکل‌های مردمی در مناطق کویری که معمولاً دارای جمعیت کمتری نسبت به دیگر اقلیم‌های مختلف هستند، دو چندان کند. همچنین، نشان دهد که طرح‌های منابع طبیعی در همه اقلیم‌های مختلف در حوزه‌های آبخیز سراسر کشور نیازمند مشارکت مردمی هستند و بدون مشارکت مردمی امکان موفقیت طرح‌های منابع طبیعی با وجود فراهم شدن همه شرایط محیطی بسیار پایین است.   مواد و روش‌ها در این پژوهش، تعداد شرکت‌های تعاونی، کمیته توسعه روستایی، صندوق‌های خرد و صندوق‌های روستایی در کل حوزه آبخیز یزدان آباد، به‌دست آمد. سپس، شناسایی توزیع روستاهای مختلف در حوزه آبخیز یزدان آباد انجام شد و فعالیت‌های اجرا شده در آنها بررسی شدند. در ادامه، جلسات برگزار شده به روش PRA در روستاهای حوزه آبخیز یزدان آباد بررسی و مقایسه تشکل‌های مردم نهاد قبل و بعد از اجرای طرح مدیریت جامع منابع طبیعی انجام شدند و مورد تجزیه و تحلیل قرار گرفتند.   نتایج و بحث نتایج پژوهش نشان داد که در حوزه آبخیز یزدان‌آباد تعداد سه شرکت تعاونی و چهار صندوق روستایی است و همچنین، در این حوضه، 16 کمیته توسعه فعال بوده که تقریباً هر روستا دارای یک کمیته توسعه است و همچنین، دو صندوق خرد نیز در حوزه آبخیز یزدان آباد وجود دارد. اجرای طرح‌های منابع طبیعی تاثیر بسیار زیادی برای ذینفعان حوزه‌های آبخیز به خصوص، حوزه‌های آبخیز مناطق کویری دارد، به شرط آنکه مردم پایه اصلی اجرای این طرح باشند و با تشویق و الگوسازی مشارکت صد در صدی از خود نشان دهند که موفقیت چنین طرح‌هایی تضمین شود. نتایج طرح‌های منابع طبیعی قبل و بعد از اجرای آنها نشان داد که اجرای طرح‌های منابع طبیعی تاثیر بسیار زیادی در معیشت مردم و همچنین، حفاظت پایدار از منابع طبیعی دارد، زیرا مردمی که دارای آگاهی بیشتری نسبت به منابع طبیعی خود داشته باشند، بهتر می‌توانند بدون کمک دولت، خودشان از منابع طبیعی موجود در حوزه آبخیزشان حفاظت کنند.   نتیجه گیری نتایج پژوهش نشان داد که بیشترین فعالیت‌های اجرایی انجام شده در همه روستاهای واقع در حوزه آبخیز یزدان آباد، تشکیل کمیته توسعه روستایی و برگزاری جلسات آشنایی با قوانین و مقررات منابع طبیعی بوده است.

Roderick W. Lammers, Matthew Chambers, Brian P. Bledsoe

Abstract Relocating levees further back from river channels to increase river–floodplain connection can reduce flood stages and provide a host of co‐benefits. Modeling case studies show the significant potential of large levee setbacks for reducing flood stages; however, the difficulty of comparing between these case studies limits our understanding of how the hydraulic effects of setbacks vary in different settings. We filled this research gap by systematically modeling the hydraulic effects of setbacks across a range of river and flood conditions. We used unsteady, 1D Hydrologic Engineering Center‐River Analysis System models to quantify changes in flood stage, channel velocity, and sediment transport capacity for various setback sizes with different river slopes, widths, floodplain roughness, and flood sizes (peak flows) and durations. Setbacks reduce flood stages within the setback, as well as up‐ and downstream. Channel velocity and sediment transport capacity both increased upstream and decreased within the setback. Channel slope, flood size, and flood duration had the largest influence on hydraulic changes. There are diminishing returns in hydraulic effects with increasing setback size. These results can help guide the design and prioritization of levee setback projects and help set reasonable expectations for the scale of changes to flood hydraulics relative to the size of the reconnected floodplain.

Lorenzo Zino, Mengbin Ye, Giuseppe Carlo Calafiore et al.

In this paper, we deal with the equilibrium selection problem, which amounts to steering a population of individuals engaged in strategic game-theoretic interactions to a desired collective behavior. In the literature, this problem has been typically tackled by means of open-loop strategies, whose applicability is however limited by the need of accurate a priori information on the game and scarce robustness to uncertainty and noise. Here, we overcome these limitations by adopting a closed-loop approach using an adaptive-gain control scheme within a replicator equation -a nonlinear ordinary differential equation that models the evolution of the collective behavior of the population. For most classes of 2-action matrix games we establish sufficient conditions to design a controller that guarantees convergence of the replicator equation to the desired equilibrium, requiring limited a-priori information on the game. Numerical simulations corroborate and expand our theoretical findings.

B. Apshikur, T. Kurmangaliyev, A. G. Goltsev et al.

Abstract. The city of Ust-Kamenogorsk, East Kazakhstan region, annually has a high risk of flooding and flooding of territories caused by spring snowmelt. These extreme phenomena are one of the most dangerous natural disasters, as they cause enormous socio-economic damage to the coastal settlements of the city. In the flood zone, agricultural and residential facilities, as well as engineering and technical infrastructure facilities are indicated. In some years, the funds allocated by the local buzhet to restore the damage caused by the disaster are not enough. One of the most effective means of stopping the consequences of such natural phenomena is an early warning system. Forecasting and modeling of hydrological phenomena can be provided using new IT technologies, some of which are Geoinformation technologies (GIS technologies) based on the cartographic method.In addition to modern advanced data processing methods in the GIS environment, the article presents a water collection design for emergency protection by calculating the main influencing factors of flooding and determining specific scales of flood levels in river valleys near settlements, determining the area of reservoirs collected at a risk control point at specific flood sites, as well as analyzing the detected ers material. The prospects for the use of GIS technologies as a means of forecasting and modeling floods caused by annual floods during the spring snowmelt period are also outlined, an analysis of the real situation is carried out, and a simple design of the shore for use in extreme conditions during periods of flooding is given.

Hyeontae Moon, Sunkwon Yoon, Junghwan Lee et al.

Abstract Global climate change is intensifying flood damage in urban rivers. Notably, most small and medium‐sized urban rivers have a brief concentration period and are highly vulnerable to sudden heavy rains that lead to a rapid increase in water levels. Therefore, rapid flood forecasting must be performed through accurate flood occurrence and timing prediction. In this study, a flooding time nomograph (FTN) was proposed to predict the flood occurrence time according to rainfall conditions, such as intensity, time distribution, and duration. In addition, rainfall–runoff simulations were performed by establishing different virtual rainfall scenarios using Huff's quartile rainfall time distribution. The simulation results were used to formulate the relationship between the rainfall intensity and flood occurrence time to generate the FTN. The applicability of this tool was verified through a comparison with the observed flood occurrence time for an actual rainfall event, which was highly accurate in the target watershed, with a correlation coefficient >0.8 and Nash–Sutcliffe efficiency >0.6. Therefore, the proposed FTN can be used to reasonably predict the occurrence of floods and the time of flood occurrence using only predicted rainfall information.

Andrea Maranzoni, Marco D'Oria, Carmine Rizzo

Abstract Flood hazard assessment is a fundamental step in flood risk mapping. Quantitative assessment requires hydrodynamic modelling of the flooding process in order to calculate the spatial distribution of suitable flood hazard indicators representative of flooding intensity and frequency, hence its potential to result in harm. Flood hazard indicators are usually defined by combining relevant flooding parameters, mainly flood depth and flow velocity, but also flooding arrival time, flooding duration, sediment or contamination load, and so forth. A flood hazard classification is commonly introduced to assign a hazard level to areas potentially subject to flooding. This article presents a systematic review of quantitative methods proposed in the scientific literature or prescribed by government authorities to assess the hazard associated with natural or anthropic flooding. Flood hazard classification methods are listed and compared by specifying their underlying approach (heuristic, conceptual, empirical), the exposed element which they were designed for (people, buildings, vehicles, etc.), and their fields of application (river overflow, dam‐break, levee breach, debris flow). Perspectives and future challenges in quantitative flood hazard analysis are also discussed. This review aims to help modellers and practitioners to select the most suitable flood hazard assessment method for the case study of interest.