A hydro-sedimentary modelling system for flash flood propagation and hazard estimation under different agricultural practices

Abstract. A modelling system for the estimation of flash flood flow characteristics and sediment transport is developed in this study. The system comprises of three components: (a) a modelling framework based on the hydrological model HSPF, (b) the hydrodynamic module of the hydraulic model MIKE 11 (quasi-2-D), and (c) the advection-dispersion module of MIKE 11 as a sediment transport model. An important parameter in hydraulic modelling is the Manning's coefficient, an indicator of the channel resistance which is directly depended on riparian vegetation changes. Riparian vegetation effect on flood propagation parameters such as water depth (inundation), discharge, flow velocity, and sediment transport load is investigated in this study. Based on the obtained results, when the weed cutting percentage is increased, the flood wave depth decreases while flow discharge, velocity and sediment transport load increase. The proposed modelling system is used to evaluate and illustrate the flood hazard for different cutting riparian vegetation scenarios. For the estimation of flood hazard, a combination of the flood propagation characteristics of water depth, flow velocity and sediment load was used. Next, an optimal selection of the most appropriate agricultural cutting practices of riparian vegetation was performed. Ultimately, the model results obtained for different agricultural cutting practice scenarios can be employed to create flood protection measures for flood prone areas. The proposed methodology was applied to the downstream part of a small mediterranean river basin in Crete, Greece.

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A hydro-sedimentary modeling system for flash flood propagation and hazard estimation under different agricultural practices

Natural Hazards and Earth System Science ◽

10.5194/nhess-14-625-2014 ◽

2014 ◽

Vol 14 (3) ◽

pp. 625-634 ◽

Cited By ~ 18

Author(s):

N. N. Kourgialas ◽

G. P. Karatzas

Keyword(s):

Sediment Transport ◽

Flow Velocity ◽

Water Depth ◽

Riparian Vegetation ◽

Flash Flood ◽

Flood Hazard ◽

Hydraulic Modeling ◽

Modeling Framework ◽

Mike 11 ◽

Discharge Velocity

Abstract. A modeling system for the estimation of flash flood flow velocity and sediment transport is developed in this study. The system comprises three components: (a) a modeling framework based on the hydrological model HSPF, (b) the hydrodynamic module of the hydraulic model MIKE 11 (quasi-2-D), and (c) the advection–dispersion module of MIKE 11 as a sediment transport model. An important parameter in hydraulic modeling is the Manning's coefficient, an indicator of the channel resistance which is directly dependent on riparian vegetation changes. Riparian vegetation's effect on flood propagation parameters such as water depth (inundation), discharge, flow velocity, and sediment transport load is investigated in this study. Based on the obtained results, when the weed-cutting percentage is increased, the flood wave depth decreases while flow discharge, velocity and sediment transport load increase. The proposed modeling system is used to evaluate and illustrate the flood hazard for different riparian vegetation cutting scenarios. For the estimation of flood hazard, a combination of the flood propagation characteristics of water depth, flow velocity and sediment load was used. Next, a well-balanced selection of the most appropriate agricultural cutting practices of riparian vegetation was performed. Ultimately, the model results obtained for different agricultural cutting practice scenarios can be employed to create flood protection measures for flood-prone areas. The proposed methodology was applied to the downstream part of a small Mediterranean river basin in Crete, Greece.

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Modeling Hydro-Dynamics in a Harbor Area in the Daishan Island, China

Water ◽

10.3390/w11020192 ◽

2019 ◽

Vol 11 (2) ◽

pp. 192 ◽

Cited By ~ 3

Author(s):

Yuting Li ◽

Zhiyao Song ◽

Guoqiang Peng ◽

Xuwen Fang ◽

Ruijie Li ◽

...

Keyword(s):

Sediment Transport ◽

Flow Velocity ◽

Suspended Sediment ◽

Hydrodynamic Model ◽

Transport Model ◽

Measurement Data ◽

Cross Flow ◽

Sediment Concentration ◽

Suspended Sediment Transport ◽

The Impact

This study presents an incorporation and application of a two-dimensional, unstructured-grid hydrodynamic model with a suspended sediment transport module in Daishan, China. The model is verified with field measurement data from 2017: water level, flow velocities and suspended sediment concentration (SSC). In the application on the Daishan, the performance of the hydrodynamic model has been satisfactorily validated against observed variations of available measurement stations. Coupled with the hydrodynamic model, a sediment transport model has been developed and tested. The simulations agreed quantitatively with the observations. The validated model was applied to the construction of breakwaters and docks under a different plan. The model can calculate the flow field and siltation situation under different breakwater settings. After we have analyzed the impact of existing breakwater layout schemes and sediment transport, a reasonable plan will be selected. The results show that the sea area near the north of Yanwo Shan and Dongken Shan has a large flow velocity exceeding 2.0 m/s and the flow velocity within the isobath of 5 m is small, within 0.6 m/s. According to the sediment calculation, the dock project is feasible. However, the designed width of the fairway should be increased to ensure the navigation safety of the ship according to variation characteristics of cross flow velocity in channel.

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Assessing riparian zone impacts on water and sediment movement: a new approach

Netherlands Journal of Geosciences – Geologie en Mijnbouw ◽

10.1017/s0016774600001633 ◽

2012 ◽

Vol 91 (1-2) ◽

pp. 245-255 ◽

Cited By ~ 30

Author(s):

S.D. Keesstra ◽

E. Kondrlova ◽

A. Czajka ◽

M. Seeger ◽

J. Maroulis

Keyword(s):

Sediment Transport ◽

Flow Velocity ◽

Riparian Vegetation ◽

Stream Flow ◽

Riparian Zone ◽

Channel Morphology ◽

Channel Management ◽

Water And Sediment ◽

The Impact ◽

Natural Channel

AbstractThe state of river channels and their riparian zones in terms of geomorphology and vegetation has a significant effect on water and sediment transport in headwater catchments. High roughness in natural rivers due to vegetation and geomorphological attributes generate drag on flowing water. This drag will slow water discharge, which in turn influences the sediment dynamics of the flow. The impacts of changes in the management of rivers and their riparian zone (either by catchment managers or river restoration plans) impacts both up- as well as downstream reaches, and should be assessed holistically prior to the implementation of these plans.To assess the river's current state as well as any possible changes in geomorphology and vegetation in and around the river, effective approaches to characterise the river are needed. In this paper, we present a practical approach for making detailed surveys of relevant river attributes. This methodology has the benefit of being both detailed – describing river depth, width, channel morphology, erosive features and vegetation types – but also being practical in terms of time management. This is accomplished by identifying and describing characteristic benchmark reaches (typical sites) in detail against which the remainder of the river course can be rated. Using this method, a large river stretch can be assessed in a relatively short period while still retrieving high quality data for the total river course. In this way, models with high data requirements for assessing the condition of a river course, can be parameterised without major investments on field surveys.In a small headwater catchment (23 km2) in southwestern Poland, this field methodology was used to retrieve data to run an existing model (HEC-GeoRAS) which can assess the impact of changes in the riparian and channel vegetation and channel management on sedimentation processes and stream flow velocity. This model determines the impact of channel morphology and in-channel and riparian vegetation on stream flow and sediment transport. Using four return periods of flooding (2, 10, 20 and 100 years), two opposing channel management / morphology scenarios were run; a natural channel and a fully regulated channel. The modelling results show an increase in the effect of riparian vegetation / geomorphology with an increase in return period of the modeled peak discharge. More natural channel form and increased roughness reduces the stream flow velocity due to increasing drag from flow obstructions (vegetation and channel morphological features). The higher the flood water stage, the greater the drag due to vegetation on the floodplains of natural river reaches compared to channelised sections. Slower flow rates have an impact on sediment mobilisation and transport in the river.

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A SEDIMENT TRANSPORT MODEL FOR IRRIGATION CANALS OF UZBEKISTAN

European Science Review ◽

10.29013/esr-19-3.4-104-108 ◽

2019 ◽

pp. 104-108

Author(s):

A. N. Khazratov

Keyword(s):

Sediment Transport ◽

Transport Model ◽

Irrigation Canals ◽

Sediment Transport Model

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EXPERIMENTAL STUDY ABOUT EFFECT OF SEDIMENT TRANSPORT ON FLOW VELOCITY DISTRIBUTION

Journal of Japan Society of Civil Engineers Ser B1 (Hydraulic Engineering) ◽

10.2208/jscejhe.75.2_i_877 ◽

2019 ◽

Vol 75 (2) ◽

pp. I_877-I_882

Author(s):

Atsuko MIZOGUCHI

Keyword(s):

Experimental Study ◽

Sediment Transport ◽

Velocity Distribution ◽

Flow Velocity

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VALIDATION OF AN OPEN-SOURCE AEOLIAN SEDIMENT TRANSPORT MODEL USING FIELD OBSERVATIONS FROM A BEACH-DUNE SYSTEM IN ARCATA, CALIFORNIA

10.1130/abs/2019am-338822 ◽

2019 ◽

Author(s):

Fateme Yousefi Lalimi ◽

◽

Ian J. Walker

Keyword(s):

Sediment Transport ◽

Open Source ◽

Transport Model ◽

Field Observations ◽

Dune System ◽

Sediment Transport Model ◽

Aeolian Sediment

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Sediment Transport and Water Flow Resistance in Alluvial River Channels: Modified Model of Transport of Non-Uniform Grain-Size Sediments

Water ◽

10.3390/w13152038 ◽

2021 ◽

Vol 13 (15) ◽

pp. 2038

Author(s):

Gennady Gladkov ◽

Michał Habel ◽

Zygmunt Babiński ◽

Pakhom Belyakov

Keyword(s):

Sediment Transport ◽

Water Flow ◽

Transport Model ◽

Flow Characteristics ◽

Field Measurements ◽

Field Investigation ◽

Empirical Modeling ◽

River Channels ◽

Channel Deformations ◽

East European

The paper presents recommendations for using the results obtained in sediment transport simulation and modeling of channel deformations in rivers. This work relates to the issues of empirical modeling of the water flow characteristics in natural riverbeds with a movable bottom (alluvial channels) which are extremely complex. The study shows that in the simulation of sediment transport and calculation of channel deformations in the rivers, it is expedient to use the calculation dependences of Chézy’s coefficient for assessing the roughness of the bottom sediment mixture, or the dependences of the form based on the field investigation data. Three models are most commonly used and based on the original formulas of Meyer-Peter and Müller (1948), Einstein (1950) and van Rijn (1984). This work deals with assessing the hydraulic resistance of the channel and improving the river sediment transport model in a simulation of riverbed transformation on the basis of previous research to verify it based on 296 field measurements on the Central-East European lowland rivers. The performed test calculations show that the modified van Rijn formula gives the best results from all the considered variants.

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