Modelling of Sediment Transport of the Mehadica River, Caras Severin County, Romania

Kiczko

2021

Water

The case study presents the results of numeric simulations of deformations of Vistula River bed downstream the Włocławek Dam, with and without development of the downstream dam cascade. Calculations were performed using a one-dimensional flow model MIKE11 with a river transport module. Using synthetic inflow hydrographs, predictions were performed for 39 year period (2016–2055). Results indicate that the construction of the dam cascade will reduce the erosion of the river bed downstream the Włocławek dam.

Section: Computation Methodsmentioning

confidence: 93%

Case Study: Forecasting the Lower Vistula Bed Deformation without and with Development of Dam Cascade

Kiczko

2021

Water

“…Many methods have been developed to analyze river issues, for instance, using numerical models. In the past decade, numerical modeling was used to analyze river morphology [5][6][7][8]. These studies proved the effectiveness of numerical modeling for hydrodynamic and sediment transport phenomena.…”

Section: Introductionmentioning

confidence: 93%

Effects of sluice gate operation on sediment flushing in Bekasi weir using a 1D numerical model

Zulfan,

Ginting,

Hidayat

2023

E3S Web Conf.

Sedimentation upstream of a weir is a common phenomenon, especially for a river with high sedimentation. In the long term, this can lead to problems since the discharge capacity will decrease due to the rise of the riverbed, as experienced in Bekasi Weir, West Java, Indonesia. The upstream accumulated sediments increased up to 1.5 m from its original riverbed in a decade. One of the easiest ways to overcome this issue is to return the riverbed elevation to its actual elevation by manual excavation or sediment flushing using a sluice gate. This paper discusses the effects of operating three sluice gates of the Bekasi Weir for flushing the deposited sediments. The analysis was carried out through 1D modeling using MIKE-11 software to analyze the morphological effects after flushing the sediments with variations of sluice gate opening scenarios. Finally, it was found that without any manual excavation, the flushing method with one fully-opened gate was the best solution by giving a significant upstream bed degradation of up to 1 m, reducing the upstream flood level, and maintaining the upstream-downstream freeboard. The solution could be more effective when combined with river normalization.

“…These stresses transform the rheological behavior of the mixture and increase advance of the flow front, water depth, and flooded area etc. (Contreras and Escauriaza 2020); 3) sediment increases flow resistance, reduces flow velocity, and increases the water level; 4) deposition of suspended sediment in flash flood increases river bed elevation, which causes higher water level and larger flooded areas than expected (Grozav et al, 2017).…”

Section: Introductionmentioning

confidence: 99%

Sensitivity Analysis of Flash Flood Hazard on Sediment Load Characteristics

Liu

Yang

Jin³

2021

Front. Earth Sci.

Changing climate has raised attention toward weather-driven natural hazards, such as rain-induced flash floods. The flooding model is an efficient tool used in flash flood warning and hazard management. More and more evidence showed significant impacts of sediment on hydrodynamics and flooding hazard of flash flood. But little information is available regarding flooding hazard sensitivity to sediment characteristics, which hampers the inclusion of sediment characteristics into the flash flood warning system and hazard management. This study used a 1D model to simulate flood hazards. After calibrating and validating the hydrodynamic model, we carried out simulations to test the sensitivity of flood hazard to sediment characteristics like inflow point, size distribution, and concentration. Our results showed that sediment from highly erosive slopes affects the flooding hazard more than sediment from watershed. This is particularly true when sediment particles are fine particles with a medium size of 0.06 mm. When medium particle size of sediment increased above 1 mm, most of the sediment particles are deposited in the river and we see little effect on flooding hazard downstream. Sediment concentration significantly influenced the flooding hazard but was less important than sediment inflow point and medium particle size. Our study suggested considering more characteristics than concentration when including sediment particles into the flash flood warning system.