scholarly journals Three-dimensional visualization maps of suspended-sediment concentrations during placement of dredged material in 21st Avenue West Channel Embayment, Duluth-Superior Harbor, Duluth, Minnesota, 2015

2016 ◽  
pp. 1-26
Author(s):  
Joel T. Groten ◽  
Christopher A. Ellison ◽  
Mollie H. Mahoney
Keyword(s):  
Suspended Sediment ◽  
Three Dimensional ◽  
Dredged Material ◽  
Suspended Sediment Concentrations

scholarly journals 3D numerical modeling of flow and sediment transport in rivers and open channels

2019 ◽  
Vol 3 (1) ◽  
pp. 23-36
Author(s):  
Le Song Giang ◽  
Tran Thi My Hong
Keyword(s):  
Boundary Condition ◽  
Sediment Transport ◽  
Numerical Model ◽  
Differential Equations ◽  
Water Level ◽  
Suspended Sediment ◽  
Three Dimensional ◽  
River Bed ◽  
Suspended Sediment Concentrations ◽  
Flow And Sediment Transport

Numerical model is a useful tool in studying the flow and sediment transport, change in river bed and is built on solving governing differential equations. Numerical model has many different levels and three-dimensional model is the highest level, allowing detailed simulation of flow and sediment transport process in 3D space. The paper presents a method calculating three - dimensional flow and sediment transport in the open channel. Water level and flow velocity are solved from three-dimensional equations with hydrostatic hypothesis. Concentration of suspended sediment, bottom sediment and bottom evolution is solved from transport equations. The governing differential equations in the "sigma" transform coordinate system are solved by finite volume method on unstructured grid of quadrilateral elements. Boundary condition of water level or flow will be imposed on open boundary. For suspended sediment concentrations in the injected phase, suspended sediment concentrations are applied and the outflow phase applies free drainage conditions. This method of calculation was tested with the problem of curved channel sediment transport which was studied experimentally by Odgaard and Bergs. Calculation results are quite consistent with the measured data. In order to test the practical applicability, this method is also tested with the problem of sediment transport in Cu lao Pho islet on Dong Nai river. To solve the matter of hydraulic boundary condition of this problem, the model of Cu lao Pho islet is integrated into the Sai Gon - Dong Nai river system model. Results of the calculation of the river bed evolution of the Cu lao Pho islet on the Dong Nai river also show that this calculation method gives results consistent with the rule and can be used in practical research.  

Use of a three-dimensional model to predict heavy metal (copper) fluxes in the Oujiang estuary

2014 ◽  
Vol 69 (6) ◽  
pp. 1334-1343 ◽  
Author(s):  
Shasha Lu ◽  
Ruijie Li ◽  
Xiaoming Xia ◽  
Jun Zheng
Keyword(s):  
River Discharge ◽  
Water Surface ◽  
Three Dimensional ◽  
Measured Data ◽  
Dimensional Model ◽  
Three Dimensional Model ◽  
Pollutant Concentrations ◽  
Suspended Sediment Concentrations ◽  
Adsorption Desorption ◽  
Good Agreement

Measuring pollutant concentrations in major tributaries is the standard method for establishing pollutant fluxes to the sea. However, this method is costly and difficult, and may be subject to a great deal of uncertainty due to the presence of unknown sources. This uncertainty presents challenges to managers and scientists in reducing contaminant discharges to water bodies. As one less costly method, a three-dimensional model was developed and used to predict pollutant fluxes to the sea. The sorptive contaminant model was incorporated into hydrodynamic and sediment models. Adsorption–desorption of copper by sediments in the Oujiang estuary were described using Henry's law. The model was validated using measured data for water surface elevations, flow velocity/direction, suspended sediment concentrations, and the proportion of copper sorbed to sediment. The validated model was then applied to predict fluxes of copper. Combined with the measured data, the copper concentration in the Oujiang River discharge was calculated as 13.0 μg/L and copper fluxes were calculated as 52 t in 2010. This copper flux prediction was verified using measured dissolved copper concentrations. Comparisons between the modeled and measured results showed good agreement at most stations, demonstrating that copper flux prediction in the Oujiang estuary was reasonably accurate.

scholarly journals Curvas-chave de descargas de sedimentos em suspensão no Baixo São Francisco

2020 ◽  
Vol 13 (3) ◽  
pp. 1248 ◽  
Author(s):  
Solange Cavalcanti de Melo ◽  
José Coelho de Araújo Filho ◽  
Renata Maria Caminha Mendes de Oliveira Carvalho
Keyword(s):  
Suspended Sediment ◽  
Suspended Sediment Concentration ◽  
Suspended Sediments ◽  
Sediment Concentration ◽  
Gradual Reduction ◽  
Sao Francisco River ◽  
Sediment Loads ◽  
São Francisco River ◽  
Historical Series ◽  
Suspended Sediment Concentrations

RESUMOO conhecimento da análise quantitativa das concentrações de sedimentos em suspensão transportados pelo rio São Francisco bem como sua relação com as vazões é de muita importância, pois pode auxiliar na identificação dos efeitos da intervenção humana e ou ocasionados pelas condições naturais da região. As regiões a jusante dos barramentos no rio São Francisco apresentam como principal consequência a regularização das vazões e a diminuição das concentrações de sedimentos. O objetivo da pesquisa foi determinar as curvas-chave de sedimentos em suspensão (CCS) nas estações fluviométricas instaladas no Baixo São Francisco (BSF) após a barragem de Xingó. Para o estabelecimento dessas curvas foram utilizados dados de vazão e concentração de sedimentos em suspensão, obtidos do sistema Hidroweb no site da Agência Nacional da Água (ANA) no período de 1999 a 2018. Foram obtidas CCS para todo o trecho do BSF as quais apresentaram bons coeficientes de determinação. Na análise dos dados também foi possível perceber que nos últimos anos, desde 2013 houve redução gradativa das vazões disponibilizadas na barragem de Xingó. Consequentemente, houve também a redução gradativa das cargas de sedimentos em suspensão geradas nas estações de Piranhas, Traipu e Propriá, ou seja, os menores valores já registrados no BSF correspondendo as menores séries históricas tanto de vazão como de sedimentos em suspensão.  Keys curves of sediment discharges in suspension in the Lower São Francisco A B S T R A C TThe knowledge of the quantitative analysis of suspended sediment concentrations carried by the São Francisco River as well as its relation with the flows is of great importance, since it can help in the identification of the effects of human intervention and/or caused by the natural conditions of the region. In the downstream regions of the São Francisco riverbanks, the main consequence was the regularization of flow rates and the reduction of sediment concentrations. The objective of the research was to determine the key curves of suspended sediments (CCS) at the fluviometric stations installed in the lower São Francisco river after Xingó dam. For the evaluation, flow data and suspended sediment concentration were used. These data were obtained from the Hidroweb system on the website of the National Water Agency (ANA) from 1999 to 2018. CCS were plotted for all stretches and presented good coefficients of determination (R2). Based on the analysis of the data it was also possible to notice that in recent years, since 2013 there has been a gradual reduction of the flows available in the Xingó dam. Consequently, there was also a gradual reduction of suspended sediment loads generated at the Piranhas, Traipu and Propriá stations, that is, the lowest values already recorded in lower São Francisco, corresponding to the lower historical series of both discharge and suspended sediments.Keywords: dam, flow, sediments 

scholarly journals Dynamics of suspended sediment load in the upper part of the Rasina River Basin in 2010

2013 ◽  
Vol 93 (4) ◽  
pp. 23-40
Author(s):  
Sanja Mustafic ◽  
Predrag Manojlovic ◽  
Predrag Kostic
Keyword(s):  
Suspended Sediment ◽  
River Basin ◽  
Sediment Load ◽  
Suspended Sediment Load ◽  
Spring Season ◽  
Autumn Season ◽  
Specific Transport ◽  
Suspended Sediment Concentrations ◽  
Load Transport

The paper treats the issue of the suspended sediment load transport in the upper part of the Rasina River Basin, upstream from the "Celije" reservoir during the year of 2010. Measurements of the suspended sediment concentrations were being done at two hydrological profiles Brus and Ravni. Total quantity of the suspended sediment load that was transported at the profile of Brus in 2010 amounted to 3,437.3 t, which gave the specific transport of 16.4 t/km2/year. At the downstream profile of Ravni, 43,165 t of the suspended sediment load was transported, that is, 95.7 t/km2/year. The basin on the whole is characterized by the existence of two seasons, which by their characteristics in the load transport represent the extreme variants. During the winter-spring season, 74-85.8 % of the total annual load was transported, ?nd during the summer-autumn season between 14.2 and 26 %.

scholarly journals The impact of tides and waves on near-surface suspended sediment concentrations in the English Channel

Oceanologia ◽  
2017 ◽  
Vol 59 (1) ◽  
pp. 28-36 ◽  
Author(s):  
Nicolas Guillou ◽  
Aurélie Rivier ◽  
Georges Chapalain ◽  
Francis Gohin
Keyword(s):  
Suspended Sediment ◽  
English Channel ◽  
Near Surface ◽  
Suspended Sediment Concentrations ◽  
The Impact

Suspended sediment and discharge dynamics across multiple spatial and temporal scales in a glaciated alpine environment: the case of the upper Ötztal, Austria

2021 ◽  
Author(s):  
Lena Katharina Schmidt ◽  
Till Francke ◽  
Theresa Blume ◽  
Johannes Schöber ◽  
Daniel Pfurtscheller ◽  
...  
Keyword(s):  
Suspended Sediment ◽  
Temporal Dynamics ◽  
Management Strategies ◽  
Transient State ◽  
Data Availability ◽  
Spatial And Temporal Scales ◽  
Sediment Yields ◽  
Catchment Areas ◽  
Suspended Sediment Concentrations ◽  
Alpine Catchments

<p>High alpine areas are affected disproportionately by global warming and are thus found to be in a transient state. This causes accelerating glacial retreat, which can have severe impacts on discharge and potentially sediment dynamics. Possible effects include changes in water quantities and hydrograph timing as well as changing sediment source areas and the associated magnitude and timing of transport capacities. In turn, the resulting changes in water and sediment supplies and timing have the potential to severely impact downstream ecosystems and infrastructure.</p><p>An essential step towards estimating the effects of future changes and developing sustainable management strategies is to quantify the behavior in the past and present. We therefore used the excellent data availability of discharge and suspended sediment concentrations in our study area in the upper Ötztal in Tyrol, Austria, to make such an assessment. We study discharge and suspended sediment concentrations, which have been monitored at three gauges and for a minimum of seven years in the case of the youngest gauge. The resulting nested catchment setup, with catchment sizes ranging between 98 km² and 785 km², allows us to learn about discharge and sediment fluxes and their spatial distribution, thus allowing us to quantify the relative importance of the glaciated areas as compared to the lower-lying catchment areas. It also allows us to study the temporal dynamics, such as the seasonal timing of the peaks and their interannual differences. In turn, the nested catchments allows us to investigate the spatial variability of these temporal dynamics.  </p><p>The results confirm the high specific sediment yields for alpine catchments in the order of 10³ t/km² per year and higher yields in areas with higher glacier cover as well as a very pronounced seasonality.</p>

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