scholarly journals Experimental determination of the flood wave transformation and the sediment resuspension in a small regulated stream in an agricultural catchment

2017 ◽  
Vol 21 (11) ◽  
pp. 5681-5691 ◽  
Author(s):  
David Zumr ◽  
Tomáš Dostál ◽  
Jan Devátý ◽  
Petr Valenta ◽  
Pavel Rosendorf ◽  
...  
Keyword(s):  
Sediment Transport ◽  
Initial Conditions ◽  
Sediment Resuspension ◽  
Early Spring ◽  
Wave Transformation ◽  
Flood Wave ◽  
Water Saturated ◽  
Artificial Flood ◽  
Long Channel ◽  
Flood Waves

Abstract. This paper presents the methodology used for artificial flood experiments conducted in a small artificial, trained (regulated) channel on the Nučice experimental agricultural catchment (0.5 km2), central Czech Republic, and the results of the experiments. The aim was to monitor the transformation of the flood wave and the sediment transport within the channel. Two series of experiments were carried out in contrasting initial conditions: (a) in September, when the stream banks were dry, the baseflow was negligible, and the channel was fully overgrown with vegetation; and (b) in March, when the stream banks were almost water saturated, the baseflow was above the annual average, and there was no vegetation present. Within each campaign, three successive flood waves, each with an approximate volume of 17 m3 and peak flow of ca. 40 L s−1, were pumped into the upper part of the catchment drainage channel. The transformation of the flood wave and the sediment transport regime within an approximately 400 m long channel section were monitored by measuring the discharge, the turbidity, and the electrical conductivity in three profiles along the stream. On the basis of the results, it was concluded that there is a considerable amount of deposited sediment, even in the well-trained and straight channel that can be re-mobilized by small floods. Part of the recorded sediment therefore originates from the particles deposited during previous soil erosion events. The flood waves initiated in dissimilar instream conditions progressed differently – we show that the saturation of the channel banks, the stream vegetation and the actual baseflow had a strong influence on the flood transformation and the sediment regime in the channel. The sediment moves quickly in winter and early spring, but in the later part of the year the channel serves as a sediment trap and the resuspension is slower, if dense vegetation is present.

scholarly journals Experimental determination of the flood wave transformation and the sediment resuspension in a small regulated stream in an agricultural catchment

2017 ◽  
Author(s):  
David Zumr ◽  
Tomáš Dostál ◽  
Jan Devátý ◽  
Petr Valenta ◽  
Pavel Rosenforf ◽  
...  
Keyword(s):  
Initial Conditions ◽  
Sediment Resuspension ◽  
Wave Transformation ◽  
Flood Wave ◽  
Regulated Stream ◽  
Series Of Experiments ◽  
Water Saturated ◽  
Artificial Flood ◽  
Long Channel ◽  
Flood Waves

Abstract. This paper presents the methodology used for artificial flood experiments conducted in a small artificial, trained (regulated) channel on the Nučice experimental agricultural catchment (0.5 km2), central Czech Republic, and the results of the experiments. Two series of experiments were carried out in contrasting initial conditions: (a) in summer, when the stream banks were dry, the baseflow was negligible and the channel was fully overgrown with vegetation; and (b) in spring, when the stream banks were almost water saturated, the baseflow was above the annual average, and there was no vegetation present. Within each campaign, three successive flood waves, each with an approximate volume of 17 m3 and peak flow of ca 40 l s−1, were pumped into the upper part of the catchment drainage channel. The transformation of the flood wave and the sediment transport regime within an approximately 400 m long channel section were monitored by measuring the discharge, the turbidity and the electrical conductivity in three profiles along the stream. On the basis of the results, it was concluded that there is a considerable amount of deposited sediment in the channel that can be re-mobilized even by small floods. Part of the recorded sediment therefore originates from the particles deposited during previous soil erosion events. The flood waves initiated in dissimilar instream conditions progressed differently – we show that the saturation of the channel banks, the stream vegetation and the actual baseflow had a strong influence on the flood transformation and the sediment regime in the channel.

scholarly journals Nearshore Wave Transformation Domains from Video Imagery

2019 ◽  
Vol 7 (6) ◽  
pp. 186 ◽  
Author(s):  
Umberto Andriolo
Keyword(s):  
Sediment Transport ◽  
Intensity Variation ◽  
Wave Transformation ◽  
Physical Processes ◽  
Pixel Intensity ◽  
Wave Characteristics ◽  
Wide Range ◽  
Different Types ◽  
Propagation Properties ◽  
Wave Properties

Within the nearshore area, three wave transformation domains can be distinguished based on the wave properties: shoaling, surf, and swash zones. The identification of these distinct areas is relevant for understanding nearshore wave propagation properties and physical processes, as these zones can be related, for instance, to different types of sediment transport. This work presents a technique to automatically retrieve the nearshore wave transformation domains from images taken by coastal video monitoring stations. The technique exploits the pixel intensity variation of image acquisitions, and relates the pixel properties to the distinct wave characteristics. This allows the automated description of spatial and temporal extent of shoaling, surf, and swash zones. The methodology was proven to be robust, and capable of spotting the three distinct zones within the nearshore, both cross-shore and along-shore dimensions. The method can support a wide range of coastal studies, such as nearshore hydrodynamics and sediment transport. It can also allow a faster and improved application of existing video-based techniques for wave breaking height and depth-inversion, among others.

scholarly journals Application of HEC-RAS model for estimating changes in watercourse geometry during floods

2012 ◽  
Vol 34 (2) ◽  
pp. 63-72 ◽  
Author(s):  
Joanna Markowska ◽  
Jacek Markowski ◽  
Andrzej Drabiński
Keyword(s):  
River Channel ◽  
Groundwater Table ◽  
Water Levels ◽  
Primary Role ◽  
Flood Wave ◽  
Initial State ◽  
Wave Impact ◽  
Groundwater Levels ◽  
Groundwater Level Fluctuations ◽  
Flood Waves

Abstract Groundwater table levels in a river valley depend, among other factors, on meteorological and hydrogeological conditions, land use and water levels in watercourses. The primary role of a watercourse is to collect surface and groundwater, and it becomes an infiltrating watercourse at high water levels. Changes in groundwater levels and the range of these changes depend chiefly on the shape, height and duration of the flood wave in the river channel. The assessment of flood wave impact on groundwater was based on long-term measurements of groundwater levels in the Odra valley and observations of water levels in the river channel. Simulations were performed with the use of in-house software FIZ (Filtracja i Zanieczyszczenia; Filtration and Contamination), designed for modelling unsteady water flows within a fully saturated zone. A two-dimensional model with two spatial variables was employed. The process of groundwater flow through a porous medium, non-homogeneous in terms of water permeability, was described with Boussinesq equation. The equation was solved with the use of finite element method. The model was applied to assess groundwater level fluctuations in the Odra valley in the context of actual flood waves on the river. Variations in groundwater table in the valley were analysed in relation to selected actual flood water levels in the Odra in 2001-2003 and 2010. The period from 2001 to 2003 was used to verify the model. A satisfactory agreement between the calculated and the measured values was obtained. Based on simulation calculations, it was proved that flood waves observed in 2010 caused a rise in groundwater table levels in a belt of approximately 1000 metres from the watercourses. It was calculated that at the end of hydrological year 2009/2010, the highest growths, of up to 0.80 m, were observed on piezometers located close to the Odra river channel. The passage of several flood waves on the Odra caused an increase of subsurface retention by 3.0% compared to the initial state.

scholarly journals Geomorphic change and sediment transport during a small artificial flood in a transformed post-dam delta: The Colorado River delta, United States and Mexico

2017 ◽  
Vol 106 ◽  
pp. 757-775 ◽  
Author(s):  
Erich R. Mueller ◽  
John C. Schmidt ◽  
David J. Topping ◽  
Patrick B. Shafroth ◽  
Jesús Eliana Rodríguez-Burgueño ◽  
...  
Keyword(s):  
United States ◽  
Sediment Transport ◽  
Colorado River ◽  
River Delta ◽  
Colorado River Delta ◽  
Artificial Flood

scholarly journals Results and Future Prospects of the Hydro/dynamic Model of Flood Waves Spreading Use in the Amur River Basin

2017 ◽  
Author(s):  
Keyword(s):  
River Basin ◽  
Hydrodynamic Model ◽  
Model Verification ◽  
Wave Transformation ◽  
Amur River Basin ◽  
Flood Wave ◽  
Amur River ◽  
The Amur River ◽  
Far Eastern

A 2013 disastrous inundation occurred on the Amur River indicated the necessity of reaching new solutions for floods prevention and their negative consequences minimization. One of the possible ways is development of a method for setting the discharge hydrograph of the Bureya, Nizhne-Bureya and Zeya reservoirs, nonsynchronous with the forecasted hydrograph of the flood wave passage for flood-risky ranges of the Middle and Lower Amur on the basis of the flood wave transformation calculations. Results of the digital experiments on simulating the Amur runoff transformation with a hydrodynamic model developed by RosNIIVKh Far Eastern Branch on the basis of DHI-MIKE11 for the Middle and Lower Amur for information/analytical support of the Amur BWA activities on determination of the high-water passage regime for the reservoirs. As a result of the hydrodynamic model verification over the 2016–2017 period as a whole we obtained satisfactory estimations of the simulation quality criteria. On the basis of the simulation results analysis requirements to the boundary conditions have been formulated in addition to the determination of a range of practical tasks to be solved to adopt successfully the hydrodynamic simulation methods to the operative practice of the flood regulation in the Amur River basin including provision of the beds’ and floodplains’ morphometric and hydraulic characteristics relevance; the use of the runoff formation modern forecast hydrological models calculation data; and automation of the scenario calculations on the basis of integration with the Far Eastern Department of Hydro/meteorological Service state hydrological monitoring information system.

scholarly journals MODELING SEDIMENT TRANSPORT IN THE YELLOW RIVER MOUTH

2011 ◽  
Vol 1 (32) ◽  
pp. 13
Author(s):  
Haibo Zong ◽  
Pingxing Ding ◽  
Fengyan Shi
Keyword(s):  
Sediment Transport ◽  
Yellow River ◽  
Sediment Resuspension ◽  
River Mouth ◽  
Sediment Concentration ◽  
The Yellow River ◽  
Numerical Studies ◽  
Wave Effects ◽  
Coastal Sediment Transport ◽  
Yellow River Mouth

Yellow River is famous for its high sediment concentration, which carries a huge amount of sediment into Bohai Sea during the flood season. In the mouth of Yellow River, the suspended sediment concentration (here after: SSC) are relatively high and the average depth is generally shallow. Recent studies indicated that in the shallow and micro-tide area, wave usually is a primary mechanism for bottom sediment resuspension. Most numerical studies of sediment transport in the Yellow River mouth didn't include the wave effects. To analyze the sediment transport in the Yellow River mouth with wave effect, a Coastal Sediment Transport Modeling System (CSTMS) was applied in this study.

scholarly journals The role of flood wave superposition for the severity of large floods

2019 ◽  
Author(s):  
Björn Guse ◽  
Bruno Merz ◽  
Luzie Wietzke ◽  
Sophie Ullrich ◽  
Alberto Viglione ◽  
...  
Keyword(s):  
Flood Wave ◽  
Data Set ◽  
Discharge Data ◽  
Main River ◽  
Wave Superposition ◽  
Triple Points ◽  
Flood Peaks ◽  
The Impact ◽  
Flood Waves

Abstract. The severity of floods is shaped not only by event and catchment specific characteristics but also depends on river network configuration. At the confluence of relevant tributaries to the main river, flood event characteristics may change depending on magnitude and temporal matching of flood waves. This superposition of flood waves may potentially increase flood severity. However, this aspect is up to now not analysed for a large data set. To fill this gap, the role of flood wave superposition in determining flood severity is investigated. A novel methodological approach to analyse flood wave superposition is presented and applied to mean daily discharge data of 37 triple points from the four large river basins in Germany and Austria (Elbe, Danube, Rhine and Weser). A triple point consists of the three gauges at the tributary as well as upstream and downstream of the confluence to the main river. At the triple points, differences and similarities in flood characteristics are jointly analysed in terms of temporal matching and magnitudes of flood peaks. At many analysed confluences, the tributary peaks arrive consistently earlier than the main river peaks, but mostly high variability in the time lag is detected. No large differences in temporal matching are detected for floods of different magnitudes. In the majority of the cases, the largest floods at the downstream gauge occur not because of a perfect temporal matching of tributary and main river. In terms of spatial variability, the impact of flood wave superposition is site-specific. Characteristic patterns of flood wave superposition are detected for the flood peaks in the Danube, where peak discharge largely increases due to inflow from the alpine tributaries. Overall, we conclude that the superposition of flood waves is not the driving factor of flood peak severity in Germany, but a few confluences bear potential of strong flood magnifications in the case of temporal shift in flood waves.

scholarly journals The Method for Evaluating Cross-Shore Migration of Sand Bar under the Influence of Nonlinear Waves Transformation

Water ◽  
2022 ◽  
Vol 14 (2) ◽  
pp. 214
Author(s):  
Margarita Shtremel ◽  
Yana Saprykina ◽  
Berna Ayat
Keyword(s):  
Sediment Transport ◽  
Nonlinear Wave ◽  
Maximum Amplitude ◽  
Field Measurements ◽  
Wave Transformation ◽  
Sandy Bottom ◽  
Divergence Point ◽  
Sand Bar ◽  
Wave Induced ◽  
Second Wave

Sand bar migration on the gently sloping sandy bottom in the coastal zone as a result of nonlinear wave transformation and corresponding sediment transport is discussed. Wave transformation on the intermediate depth causes periodic exchange of energy in space between the first and the second wave harmonics, accompanied by changes in the wave profile asymmetry. This leads to the occurrence of periodical fluctuations in the wave-induced sediment transport. It is shown that the position of the second nonlinear wave harmonic maximum determines location of the divergence point of sediment transport on the inclined bottom profile, where it changes direction from the onshore to the offshore. Such sediment transport pattern leads to formation of an underwater sand bar. A method is proposed to predict the position of the bar on an underwater slope after a storm based on calculation of the position of the maximum amplitude of the second nonlinear harmonic. The method is validated on the base of field measurements and ERA 5 reanalysis wave data.

scholarly journals Analysis of physical mechanisms of human body instability for the definition of hazard zones present in emergency action plans of dams. Case study: Santa Helena Dam, Bahia

RBRH ◽  
2019 ◽  
Vol 24 ◽  
Author(s):  
Luan Marcos da Silva Vieira ◽  
Andrea Sousa Fontes ◽  
André Luiz Andrade Simões
Keyword(s):  
Human Body ◽  
Buoyancy Force ◽  
Flood Wave ◽  
Hazard Management ◽  
Physical Mechanisms ◽  
Adaptive Ability ◽  
Definition Of ◽  
The Individual ◽  
Flood Waves

ABSTRACT The impacts caused by flood waves due to dam ruptures usually cause irreversible damages to the resident population, and, the loss of body equilibrium in floods contributes to aggravate this scenario. In this context, this work aimed to analyse the influence of consideration of physical mechanisms that cause instability in the human body on the definition of hazard zones. Therefore, it was developed simulation of the propagation of the flood wave due to the hypothetical rupture of Santa Helena Dam in Bahia, using the hydrodynamic model HEC-RAS. The results of flow velocities and heights were related and compared to different criteria of hazard zonings and mechanisms that cause body instability. It was verified that the consideration of instability mechanisms of the human body can contribute to hazard management, through the knowledge of areas in which different individuals may topple or slide. It was confirmed that in supercritical flow regimes is more likely for the individual to slide and that in subcritical regimes the individual will topple. Moreover, the consideration of parameters such as buoyancy force and the angle related to the human body's adaptive ability in a flooding influence on the definition of zones.

scholarly journals Re-design Breakwater di PPI Tulandale Berdasarkan Analisis Hidrodinamika dan Sedimentasi. (Hal. 30-41)

2019 ◽  
Vol 5 (3) ◽  
pp. 30
Author(s):  
Regina Eugeny Destin Wirawan ◽  
Yessi Nirwana Kurniadi ◽  
Fitri Suciaty
Keyword(s):  
Sediment Transport ◽  
Neap Tide ◽  
Spring Tide ◽  
Current Speed ◽  
Transformation Model ◽  
Wave Transformation ◽  
North East ◽  
South West ◽  
Result Show ◽  
Mike 21

ABSTRAKPangkalan Pendaratan Ikan Tulandale berada di Kabupaten Rote Ndao, Provinsi Nusa Tenggara Timur. Breakwater di PPI Tulandale tidak dapat melindungi kolam pelabuhan dari gelombang tinggi. Tujuan dari penelitian ini adalah re-design breakwater pada PPI Tulandale agar dapat melindungi kolam pelabuhan. Simulasi hidrodinamika, transpor sedimen dan transformasi gelombang dilakukan dengan bantuan perangkat lunak Mike 21 untuk 2 buah skenario. Pada skenario alternatif 1, mulut pelabuhan di perkecil menjadi 50 m dan skenario alternatif 2 pada kondisi breakwater eksisting ditambah bangunan breakwater tegak lurus garis pantai sepanjang 200 m. Simulasi dilakukan selama 15 hari. Hasil analisis pada pemodelan, kondisi arus saat pasang purnama dan perbani bergerak dari arah barat daya kearah timur laut dengan kecepatan 0,00–0,08 m/s untuk alternatif 1, sedangkan kecepatan arus alternatif 2 arus sebesar 0,08–0,16 m/s. Hasil pemodelan hidrodinamika, transpor sedimen dan transformasi gelombang menunjukan bahwa bentuk re-design breakwater pada alternatif 2 efektif untuk melindungi kolam pelabuhan di PPI Tulandale karena dapat mereduksi gelombang sebesar 46,7% dari gelombang diluar kolam pelabuhanKata kunci: re-design breakwater, hidrodinamika, sedimentasi ABSTRACTTulandale Fishing Port Tulandale is located in Rote Ndao district, The province of Nusa Tenggara Timur. The Breakwater in Tulandale Fishing Port could not protect the port basin from the height of waves. The aimed of this study is to re-design breakwater in Tulandale Fishing Port in order to protect the port basin. The Hydrodynamic, sediment transport and waves transformation simulation are applied in this study by using mike 21 software for 2 scenarios. In the first scenario, the port basin width is reduced to 50 m and the second scenario is using the existing breakwater condition with the added breakwater building Perpendicular along the coast line for 200m. The simulation run of 15 days. The result show that the condition during the spring tide and neap tide move from south west to north east with 0.00-0.08 m/s for first scenario, while the current speed for the second scenario is is 0.08-0.16 m/s. Hydrodynamic result, sediment transport and wave transformation model that the shape of re-design breakwater on the second scenario more effective to protect the port basin at The Tuandale Fishing Port because the wave decrease at 46.7% from outside the port basin.Keywords: re-design breakwater, hydrodynamics, sedimentation

Sign in / Sign up

Export Citation Format

Share Document