Flooding Phenomena Research Articles

Current and future variability of water supply to a mountain reservoir (Polish Carpathians)

AbstractThis study presents the characteristics of the current course of the phenomenon of droughts and floods in the catchment area of a man-made mountainous reservoir and forecasts of water inflow changes to the reservoir over the next three decades. The catchment area of the Klimkówka reservoir on the Ropa River, a tributary of the Wisłoka River, located within the Polish Carpathians was selected for the study. The analysis carried out, using Soil and Water Assessment Tool (SWAT) modelling among other techniques, showed an increase in the importance of low-flow outflow from the upper Ropa catchment and a negative balance of inflow to the reservoir (Q < 2 m3 s−1), manifested by a prolonged duration of low flows and an increase in outflow deficit during the year. The duration of flood flows and the runoff excess during these periods show a constant or decreasing tendency, while the length and excess of runoff increase during large floods. Thus, in the upper Ropa catchment, an increase in the intensity of extreme hydrological phenomena is observed. The prepared forecasts indicate an increase in annual runoff from the catchment in the decades 2021–2030 and 2031–2040 and a marked decrease in the decade 2041–2050. In the annual cycle, the projected changes in the coming decades will take different directions. In December only, throughout the entire period 2021–2050, the outflow will increase, whereas in May it will systematically decrease.

Risk Evaluation of Ice Flood Disaster in the Upper Heilongjiang River Based on Catastrophe Theory

The ice flood phenomenon frequently occurs in frigid locations of high latitude and high altitude, which triggers ice dam or ice jam flooding thus endangering personal and property safety. Hence, a scientific risk evaluation with enough consideration of each factor is a basic and necessary requirement for preventing ice flood disaster risks. This study establishes a risk evaluation system for ice flood disasters based on the catastrophe theory and utilizes the Pearson correlation coefficient to screen underlying indicators to evaluate the risk of ice flood in the upper Heilongjiang River region. Considering the correlation between different indicators, a hierarchical cluster analysis is invoked to simplify the indicator set and to select typical years. The results of the evaluation system indicate that the catastrophe membership values in the Mohe, Tahe, and Huma regions from 2000 to 2020 ranged from 0.86 to 0.93. Based on the membership values and the actual disaster situations, a four-level classification of risk ratings is conducted. The comparison between the results obtained from the catastrophe theory evaluation method and the fuzzy comprehensive evaluation method reveals similar risk levels, which verifies the effectiveness and practicality of the catastrophe theory applied to the ice flood risk evaluation and presents a novel method for the study of ice floods.

Komunikasi Lingkungan: Motivasi dan Taktik Komunitas dalam Perbaikan Sosiokultural Masyarakat Pesisir Sungai Banjarmasin

The phenomenon of flooding and damage to river ecosystems in the City of Banjarmasin is one of the unresolved sociocultural problems. The Friends of the River Community is present in the Banjarmasin City community in trying to solve this problem. This paper describes the motivations and tactics of Sahabat Sungai Community in conveying messages of change to riverside communities in Banjarmasin by using methods, strategic ideas, and communication strategies to manage and protect the environment, in an effort to spread messages about environmental sustainability. Sungai about their motivations and tactics and see the direct influence on the riverside community in Banjarmasin. This article contributes to an understanding of agenda setting, environmental communication, and the communication techniques that communities use to convey their messages

Water Management Capacity of Metal Foam Flow Field for PEMFC under Flooding Situation.

Porous metal foam with complex opening geometry has been used as a flow field to enhance the distribution of reactant gas and the removal of water in polymer electrolyte membrane fuel cells. In this study, the water management capacity of a metal foam flow field is experimentally investigated by polarization curve tests and electrochemical impedance spectroscopy measurements. Additionally, the dynamic behavior of water at the cathode and anode under various flooding situations is examined. It is found that obvious flooding phenomena are observed after water addition both into the anode and cathode, which are alleviated during a constant-potential test at 0.6 V. Greater abilities of anti-flooding and mass transfer and higher current densities are found as the same amount of water is added at the anode. No diffusion loop is depicted in the impedance plots although a 58.3% flow volume is occupied by water. The maximum current density of 1.0 A cm-2 and the lowest Rct around 17 mΩ cm2 are obtained at the optimum state after 40 and 50 min of operation as 2.0 and 2.5 g of water are added, respectively. The porous metal pores store a certain amount of water to humidify the membrane and achieve an internal "self-humidification" function.

Design and Research on online Monitoring of Liquid Flooding in Distillation Towers

The phenomenon of liquid flooding, as a special flow state in gas-liquid countercurrent processes, can cause adverse effects such as reduced production efficiency and increased energy consumption, seriously restricting the operation and design of gas-liquid mass transfer equipment. Real time monitoring of the operation status of the packed tower not only ensures its normal operating conditions, but also helps to improve equipment efficiency, which has important practical significance and industrial application prospects. This article first reviews the current research status of liquid flooding monitoring, and proposes to use the key variable of tower pressure difference as an important variable for liquid flooding monitoring to monitor and regulate the pressure difference inside the tower. The effectiveness and superiority of monitoring have been verified through experiments, which can achieve indirect monitoring of liquid flooding.

Mapping subsurface defects and surface deformation along the artificial levee of the Lower Tisza River, Hungary

Artificial levees along alluvial rivers are major components of flood-risk mitigation. This is especially true in the case of Hungary, where more than one-third of the country is threatened by floods and protected by an over 4200-km-long levee system. Most of such levees were built in the nineteenth century. Since then, several natural and anthropogenic processes, such as compaction and erosion, might have contributed to these earth structures' slow but steady deformation. Meanwhile, as relevant construction works were scarcely documented, the structure and composition of artificial levees are not well known. Therefore, the present analysis mapped structural differences, possible compositional deficiencies, and sections where elevation decrease is significant along a 40-km section of the Lower Tisza River. Investigations were conducted using real-time kinematic GPS and ground-penetrating radar (GPR). Onsite data acquisition was complemented with an analysis using a Persistent Scatterer Synthetic Aperture Radar to assess general surface deformation. GPR profiles showed several anomalies, including structural and compositional discontinuities and local features. The GPR penetration depth varied between 3 and 4 m. According to height measurements, the mean elevation of the levee crown decreased by 8 cm in 40 years. However, the elevation decrease reached up to 30 cm at some locations. Sections affected by structural anomalies, compositional changes, and increased surface subsidence are especially sensitive to floods when measurement results are compared with flood phenomena archives.

Structural flood control model based on Eco-hydraulic in small watersheds (Case study of the Akelaka-Halmahera river)

Various factors, such as the physical condition of the area, nature, and humans, influence the phenomenon of flooding. Thus, the flood control application model will differ in each region. The application of flood control structurally lowers the flood water level significantly, but it changes the ecosystem around the river. The eco-hydraulic concept is a new paradigm in watershed management to reduce the impact of floods while still paying attention to river ecosystems. This study aims to integrate structural methods with eco-hydraulic concepts in flood control in small-scale watersheds. The locus is the Akelaka watershed on Halmahera Island. Watershed morphometric analysis using the ArcGIS application, hydrological analysis for five and 25-year return floods, and hydraulics testing using the HecRAS application are used. The application of this concept uses vegetation on river slopes after normalization. The results showed that flood control which combined normalization, eco-hydraulic and structural ideas in Akelaka village, showed excellent results. The potential for inundation is reduced by up to 93% for a five-year return period flood discharge and 89% for a 25-year return period flood discharge.

Streamflow Simulation in Semiarid Data-Scarce Regions: A Comparative Study of Distributed and Lumped Models at Aguenza Watershed (Morocco)

In semi-arid regions such as the southwestern zone of Morocco, better management of water resources is crucial due to the frequent flooding phenomena. In this context, the use of hydrological models is becoming increasingly important, specifically in the Aguenza watershed. A multitude of hydrological models are available to make very efficient modeling, and from this perspective, a comparative approach was adopted using two models with different characteristics. Streamflow simulations were carried out continuously at daily time steps using GR4J and ATHYS (2002–2011). The latter was used also to simulate rainfall-runoff events (1984–2014). Simulation results using the distributed model are very efficient compared to those obtained by the lumped model “GR4J”, which shows the disadvantages of neglecting the hydrological processes during a hydrological study. However, a remarkable improvement was observed in the general appearance of the resulting hydrographs and the performance parameters after using the distributed model ((Calibration: NSE, RSR, and PBIAS increased successively by 8%, 6%, and 45.2%); (Validation: NSE, RSR, and PBIAS increased successively by 6%, 4%, and 8.9%)). In terms of flood event simulations, a good concordance between observed and simulated discharge was observed (NSEmedian = 0.7), indicating its great reliability for simulating rainfall-runoff events in semi-arid and data-scarce regions. This research highlights the importance of using hydrological models, specifically the distributed model ATHYS, for the better management of water resources in semi-arid regions with frequent flooding events.

Methods for Studying Maximum Flows. Application to the Wadi Sebdou Watershed (Tafna - NW Algeria)

step in the studies of strategic projects for the prevention and management of flood phenomena in at-risk watersheds. The Oued Sebdou watershed is a tributary of the Tafna, with an area of 439.3 km2, characterized by a semi-arid climate. It has an elongated form, with a lithology that favors flow (Bouanani, 2004). The objective of this study is to analyze the morphological characteristics, the rainfall regime and the determination of the frequency of floods, using the different empirical formulas that have been developed in the Algerian context for use in specific areas. The errors generated by the application of these formulas can lead to serious technical, financial and environmental problems such as a wrong dimensioning of storage or protection works, an erroneous cartography of the floodable zones whose consequences would be disastrous. In this work, the analysis of the error of using these formulas in the Sebdou sub-basin was established. Also, the Gradex method was tested in this study. The results indicated that the GIANDOTTI method is the most reliable with a relative error of 19.7% (T=1000years), and the formulas of SOKOLOVSKY and TURRAZA are satisfactory and give flows close to those obtained from observations in the Sebdou hydrometric station

ANALISIS PEMASANGAN BOX CULVERT (2 m x 1.5 m) SEBAGAI SALURAN PENYEIMBANG DI KM 54+490 SAMPAI DENGAN KM 55+070

Train is one of the land transportation infrastructure that have an important role in distributing things and passengers. However, currently there are still some obstacles in the operation of the railway, mainly caused by natural disasters. In general, the National DisasterManagement Agency (BNPB) noted that 95% of disasters that occurred in Indonesia were dominated by hydrometeorological disasters, one of which was flooding.In February 2021, there was a flood on the railway line, precisely between Lemahabang -Kedunggedeh Station, DAOP 1 Jakarta on the rail line KM54+490 to KM 55+070 which caused the body of the upstream and downstream rail lines collapse, resulting in the cessation of the train operations.Therefore, a total of 31 box culverts will be planned to drain the 5-year flood discharge and become a balancing channel for the railroad if the flood phenomenon occurs again

Urban Flooding in Vancouver, Canada

Flooding can have devastating, long-lasting, and costly consequences, including the loss of life and displacement of communities. This review report summarizes the background, causes, and management practices of various urban flooding forms and mitigation efforts in Vancouver, British Columbia (BC) which is located on the Western part on the Pacific coast of Canada. The report makes use of existing literature to understand the flooding phenomena in Vancouver. The city is unique from a flood planning or management perspective because the city is vulnerable to every type of major flooding event, including pluvial, fluvial, and coastal flooding. Nevertheless, Vancouver is considered a globally sustainable city. As such, this report reviews various articles and research to determine the background and causes of various forms of floods experienced in Vancouver and the management practices put in place to mitigate flooding in the city. The study identifies measures in place to address every type of flooding event.

Making Education Support Media About Flood Hazard in Samarinda in the Form of Digital Comic

Samarinda is the capital of East Kalimantan that is currently growing rapidly. However, the city of Samarinda still has a complex flood problem. This flood phenomenon occurs not only when it is the rainy season but also when it rains for 1-2 hours. This condition interferes with the activities of the community and the government in Samarinda in carrying out daily activities because it can immerse settlements and housing, damage public facilities, and cause casualties. Despite the frequent occurrence and inconvenience of the community, Samarinda's level of public awareness in preventing floods is still minimal. This can be seen from the large number of communities that still often throw garbage carelessly into rivers, especially residents living near rivers. The garbage thrown into the river hinders the flow of water to the point where it can create a high puddle. It is seen that there are many communities, especially young people who are open-minded about environmental issues. Therefore, it is necessary to design a flood prevention educational medium in Samarinda city that can start from oneself or a simple thing with the main target is Samarinda people itself, especially the youth with qualitative methods.

Assessment of flood dynamics in a mountain stream using high‐resolution river flow records

AbstractUnderstanding the streamflow hydrodynamics is important for forecasting flooding phenomena in mountainous rivers. Accordingly, based on long‐term runoff observations obtained using diverse runoff techniques (i.e., rating curves and fluvial acoustic tomography (FAT)), the authors (1) evaluated and explored flood phenomena, (2) discussed the effects of dams on flood hydrograph, (3) and revealed backwater effects caused by river channel bends, sand bars, and floodplains. The duration and slope of the falling limb of the hydrograph were directly influenced by the catchment characteristics that affected runoff recession, whereas the behaviour of the rising limb of the hydrograph was directly influenced by rainfall. A weaker correlation between discharge and rainfall in higher flood events indicates that rainfall events were strongly altered by water released from dams in the basin. Additionally, because of the backwater effects, the rate at which the flow velocity and boundary shear stress changed with the increasing discharge was reduced, potentially slowing the pace of erosion. Our findings are relevant for managing mountain rivers, particularly in river bend reaches prone to backwater effects. The FAT method could help increase the ability to monitor short‐term fluctuations in floods and associated hazards.

Study of floods on the rivers of the Kaliningrad region at the beginning of 2020 in the absence of snow cover and ice

To develop measures for engineering protection of territories from flooding, it is necessary to identify spatiotemporal patterns in the formation of floods, since they are the cause of devastating floods in recent years. The paper presents the results of an analysis of flood phenomena on the rivers of the Kaliningrad region at the beginning of 2020. An array of observational data on daily water flows in rivers was processed, and the main components of the water balance of river basins were assessed by month (amount of precipitation, evaporation layer, monthly river flow layer, change in basin moisture reserves). It was found that the greatest amount of runoff was in February, while the highest amount of precipitation was in June; the highest runoff coefficient was in March and February (0.41), and in June it was only 0.03. Presumably, the main reasons for such phenomena are the distribution of the evaporation layer within the year and a decrease in the permeability of the upper soil layer for precipitation at low temperatures.

Three Phase Linear State Estimation Method of Substation Based on Zero Impedance Model

In order to improve the ability to detect and identify topological errors and measurement errors, and further enhance the rapidity and reliability of substation state estimation, this paper proposes a three-phase linear state estimation method for substations based on zero impedance model. Firstly, for the shortcomings of the traditional regularized weighted residual method with many cycles and slow calculation speed, improvements are made to improve the rapidity of state estimation while suppressing the residual flooding phenomenon. Based on this, the zero-impedance model of the substation makes full use of the three-phase telemetry and telecommunication state data to establish the power measurement equation for zero-impedance initial power state estimation, and proposes a discrimination method to identify measurement errors and topological errors and to determine the state of the switching circuit breakers. Based on the secondary power state estimation, a voltage measurement equation is established based on the voltage measurement information to estimate the substation voltage state. The simulation results show that the method can accurately identify and locate the simultaneous measurement errors and topology errors, and can also identify individual measurement errors, thus improving the estimation accuracy of state estimation.

Using GIS and Multicriteria Analysis to Map Flood Risk Areas of the Tongo Bassa River Basin (Douala, Cameroon)

Sone Essoh, W.; Onguene, R.; Ndongo, B.; Nshagali, G.; Colmet-Daage, A.; Guillaume, M.; Iroume, J.; Stieglitz, T.; Besck, F.; Efole Ewoukem, T.; Tomedi Eyango, M.; Etame, J., and Braun, J.J., 2023. Using GIS and multicriteria analysis to map flood risk areas of the Tongo Bassa River Basin (Douala, Cameroon). Journal of Coastal Research, 39(3), 531–543. Charlotte (North Carolina), ISSN 0749-0208. The present study aimed to map the areas at risk of flooding in the Tongo Bassa watershed (42 km2) located in the heart of the Cameroonian economic capital (Douala) in the tropical zone of Central Africa, more precisely in the Wouri Estuary, at the bottom of the Gulf of Guinea. Like most of the world's major cities, Douala is subject to floods. The methodological approach was to identify the flooding risk determinants in the area from an extensive literature review and field surveys and then analyze these factors and map areas at risk of flooding using the analytical hierarchy process approach coupled with the GIS environment. The results revealed that four parameters of the natural environment (elevation, drainage density, distance to the river, and land cover) were the factors that mainly influenced the phenomenon of flooding in the region. Three major classes of flood risk were highlighted: low risk, medium risk, and high risk. To validate the effectiveness of the flood risk map obtained, the flood points collected in the field were cross-checked for ground truth after a flood occurred in the watershed. This cross-check between the resulting map and the flood points using GIS tools showed a good representation of the flooded area. This result is quite interesting because the areas where the risk of flooding is high are consistent with those where flooding is most frequent. The presented results constitute a basic decision support tool for the management of flood zones by the public authorities and the decentralized territorial communities of the city of Douala.

MANIPULATION OF FLOOD CONTROL CHANNEL PROFILE IN THE KEK LIKUPANG, PANTAI PULISAN, INDONESIA

Flood, erosion, and sedimentation have become classic problems in the river. The two main parameters that significantly affect the phenomenon of flood are flow and sediment. Flood and sediment transport cause aggradation and degradation of the river bed, bring the bad influence to the construction in the river and environment. Therefore, it becomes important to conduct the manipulation of flood control channel profile in the selected area of Special Economic Area (KEK) that is Likupang, Pantai Pulisan. This research intends to obtain the design of channel shape and dimension for controlling the disasters that are influenced by the factors of environment, water resources, and climate change. One of the urgent factors in this research is to produce a design/recommendation for minimizing the negative impact that is triggered by floods and sediment transport, so it causes the disaster of geology and ecology. To reach the research aim, we carried out the survey of the existing conditions for determining the suitability of the analysis that will be used. The dimension of rainfall and watershed characteristics becomes the input in the HEC-HMS software for obtaining the design flood. Additionally, there is carried out the measurement/mapping of the river geometry. This is used in the application of HEC-RAS that will simulate the real-time flow condition in the field. Based on the analysis results of the flood control channel profile manipulation, there is obtained the dimension of multi-stage trapezoid channel with an upper width (La) of 10 m, lower width (Lb) of 1 m, and depth (h) of 3 m that can flow the design flood in amount of 36.5 m3/s (Q25). This information is a recommendation/reference in determining the management method of the environment and water resources in the Special Economy Area (EK) in the Likupang tourism-Pantai Pulisan as a super-priority tourism destination in making effort of disaster mitigation that is influenced by the factors of environment, water resources, and climate change.

GIS-Based Assessment of Fire Effects on Flash Flood Hazard: The Case of the Summer 2021 Forest Fires in Greece

Greece, like the rest of the Mediterranean countries, faces wildland fires every year. Besides their short-term socioeconomic impacts, ecological destruction, and loss of human lives, forest fires also increase the burnt areas’ risk of flash flood phenomena, as the vegetation, which acted in a protective way against runoff and soil erosion, is massively removed. Among the most severe wildland fire events in Greece were those of summer 2021, which were synchronous to the very severe heat waves that hit the broader area of the Balkan Peninsula. More than 3600 km2 of land was burnt and a significant amount of natural vegetation removed. Three of the burnt areas are examined in this work, namely, Attica, Northern Euboea, and the Peloponnese, in order to assess their risk of future flash flood events. The burnt areas were mapped, and their geological and geomorphological features studied. Flash flood hazard assessment was accomplished through a Boolean logic-based model applied through Geographic Information Systems (GIS) software, which allowed the prioritization of the requirement for protection by identifying which locations were most prone to flooding. The largest part of our study areas is characterized by geomorphological and geological conditions that facilitate flash flood events. According to our findings, in almost all study areas, the regions downstream of the burnt areas present high to very high flash flood hazard, due to their geomorphological and geological features (slope, drainage density, and hydrolithology). The only areas that were found to be less prone to flood events were Vilia and Varimpompi (Attica), due to their gentler slope inclinations and overall geomorphological characteristics. It is known that vegetation cover acts protectively against flash floods. However, in this case, large areas were severely burnt and vegetation is absent, resulting in the appearance of flash floods. Moreover, imminent flooding events are expected to be even more intense in the areas downstream of the burnt regions, possibly bearing even worse impacts on the local population, infrastructure, etc.

Preliminary identification of areas suitable for Sustainable Drainage Systems and Managed Aquifer Recharge to mitigate stormwater flooding phenomena in Rome (Italy)

This paper proposes a preliminary and large-scale survey methodology to identify areas suitable for indepth analysis for the application of Sustainable Drainage Systems and Managed Aquifer Recharge. These techniques are frequently applied to increase the natural infiltration capacity of water into the ground and their effectiveness depends on the local hydrogeological and morphological characteristics. The study area is the city of Rome where the aim is to mitigate the problems related to rainwater which, in case of extreme events, struggles to infiltrate into the ground, overloads the undersized drainage systems, and floods the urban space.The proposed method involves GIS geospatial analysis of the permeability of outcropping lithologies, the digital elevation model, and the piezometric levels of the aquifers. To identify the suitable zones, areas characterised by high permeability and a piezometric level that would confer a volumetric capacity to possibly store even large quantities of water, without triggering possible problems of water table rise, were identified. Data were divided into classes and indexed to compare and overlap them. Furthermore, the final result was compared with the urban flooding phenomena and the soil permeability map of Rome. The results of the performed analysis show that the preliminary suitable conditions to apply SuDS and MAR in Rome are widespread. The geological setting of the city is characterised by permeable lithologies in many places with an effective infiltration potential that would allow rainwater to infiltrate the subsoil and reach the first available aquifer.

SUSTAINABILITY ANALYSIS OF RIVER FLOW MANAGEMENT

The role of the Wae Batu Gajah watershed which has a function to regulate water management and as a water source is currently starting to experience a very significant change with the rate of change of forest land cover into settlements which ultimately destroys the sustainability of the ecological function. This damage can be proven by the phenomenon of flooding and that occurs in the rainy season and drought in the dry season. The analysis of the sustainability of the Wae Batu Gajah watershed has the following objectives: 1). Analyzing the index and sustainability status of the Wae Batu Gajah watershed from the ecological, economic and social dimensions. 2). Testing the validity and testing the accuracy of the sustainability index of the Wae Batu Gajah watershed management. The results of the study show that the multidimensional sustainability index for the three ecological, economic and social dimensions is 50.97% in the moderately sustainable category. The validation test shows the difference in the value of the Monte Carlo and MDS analysis at the 95% confidence level the average for the three dimensions is 0.72%; the value of determination (R 2 ) between 93.86% - 95.18% means that the sustainability index estimation model is good and adequate; stress value 0.2 which means that the MDS analysis model obtained has a high accuracy (g oodness of fit ) to assess the sustainability index of the Wae Batu Gajah watershed.