Study of sediment transport and deposition in the Kuma River and tidal flat for evaluation of environmental impact associated with removal of the Arase Dam

The Blue Stream pipeline project is a gas transportation system for the delivery of processed gas from a gas station in the southern Russia across the Black Sea to Ankara, Turkey. The Turkish landfall of the offshore pipeline in the Black Sea is located near Samsun, see Figure 1 for the pipeline route. One of the main aspects of the design of pipeline through a morphologically dynamic area such as landfall is the required burial depth (Chen et al, 1998, 2001 and Bijker et al 1995). The burial depth is the result of an optimisation between: • safety of the pipeline (which often requires a large burial depth), and • environmental impact and trenching costs (a small burial depth means less dredging and less environmental impact). This paper presents a method of predicting the future extremely low seabed level in a morphologically dynamic landfall area, which is required to determine the burial depth of the pipeline. Both short term and long term coast evolution were assessed to quantify the expected lowest seabed level along the pipeline route in the landfall area during the pipeline lifetime of 50 years. The results were used to determine the required pipeline burial depth. The long term morphological changes originate from long term variations in the morphological system (e.g. river input), gradient in the longshore sediment transport and long term variations in the hydrodynamic conditions. The short-term morphological changes originate from beach profile variations due to cross-shore sediment transport as a result of seasonal and yearly variations in the wave and current conditions. Numerical modelling was applied to compute the longshore and cross-shore sediment transport rates and the resulting coastline evolution and cross-shore profile evolution. The longshore transport model was validated using the available data on the coastline changes in the past 20 years, which was derived from the satellite images. The 50-year lowest seabed level has been determined as the sum of the coastline retreat and the cross-shore evolution in the next 50 years.

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APPLICTION OF SIMULATION MODEL FOR COHESIVE SEDIMENT TRANSPORT AND BOTTOM TOPOGRAPHY CHANGES TO TIDAL FLAT

PROCEEDINGS OF HYDRAULIC ENGINEERING ◽

10.2208/prohe.52.1333 ◽

2008 ◽

Vol 52 ◽

pp. 1333-1338

Author(s):

Toyoaki MISHIMA ◽

Takao YAMASHITA ◽

Tomoaki KOMAGUTI ◽

Fitri RIANDINI

Keyword(s):

Sediment Transport ◽

Simulation Model ◽

Tidal Flat ◽

Bottom Topography ◽

Cohesive Sediment ◽

Cohesive Sediment Transport

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The Impact of Wind on Flow and Sediment Transport over Intertidal Flats

Journal of Marine Science and Engineering ◽

10.3390/jmse8110910 ◽

2020 ◽

Vol 8 (11) ◽

pp. 910

Author(s):

Irene Colosimo ◽

Paul L. M. de Vet ◽

Dirk S. van Maren ◽

Ad J. H. M. Reniers ◽

Johan C. Winterwerp ◽

...

Keyword(s):

Sediment Transport ◽

Tidal Flat ◽

Large Scale ◽

Tidal Flow ◽

Interaction Model ◽

Sediment Concentration ◽

Momentum Balance ◽

Shear Stresses ◽

Intertidal Flats ◽

The Impact

Sediment transport over intertidal flats is driven by a combination of waves, tides, and wind-driven flow. In this study we aimed at identifying and quantifying the interactions between these processes. A five week long dataset consisting of flow velocities, waves, water depths, suspended sediment concentrations, and bed level changes was collected at two locations across a tidal flat in the Wadden Sea (The Netherlands). A momentum balance was evaluated, based on field data, for windy and non-windy conditions. The results show that wind speed and direction have large impacts on the net flow, and that even moderate wind can reverse the tidal flow. A simple analytical tide–wind interaction model shows that the wind-induced reversal can be predicted as a function of tidal flow amplitude and wind forcing. Asymmetries in sediment transport are not only related to the tide–wind interaction, but also to the intratidal asymmetries in sediment concentration. These asymmetries are influenced by wind-induced circulation interacting with the large scale topography. An analysis of the shear stresses induced by waves and currents revealed the relative contributions of local processes (resuspension) and large-scale processes (advection) at different tidal flat elevations.

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Field Observation on Suspended Sediment Transport Process off Tidal Flat in Upper Ariake Bay

Journal of Japan Society of Civil Engineers Ser B2 (Coastal Engineering) ◽

10.2208/kaigan.66.966 ◽

2010 ◽

Vol 66 (1) ◽

pp. 966-970

Author(s):

Yasuyuki NAKAGAWA ◽

Tomohiro KUWAE

Keyword(s):

Sediment Transport ◽

Suspended Sediment ◽

Tidal Flat ◽

Field Observation ◽

Transport Process ◽

Suspended Sediment Transport ◽

Ariake Bay

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VEGETATION INFLUENCED HYDRODYNAMICS AND SEDIMENT TRANSPORT

Coastal Engineering Proceedings ◽

10.9753/icce.v36.sediment.13 ◽

2018 ◽

pp. 13

Author(s):

Sha Lou ◽

Ming Chen ◽

Shuguang Liu ◽

Guihui Zhong

Keyword(s):

Sediment Transport ◽

Transition Zone ◽

Storm Surge ◽

Wave Energy ◽

Tidal Flat ◽

Morphological Evolution ◽

Energy Reduction ◽

Physical Processes ◽

Ecological Regime ◽

Flume Study

Tidal flat is a transition zone between land and ocean. Vegetation in tidal flat can protect the coastal areas from storm surge and tsunamis by wave energy reduction. Tidal flat also can filter parts of the artificial contaminations and reduce the pollutants discharged into the ocean. In addition, interactions between vegetation and morphology over tidal flat have strong impacts on ecological regime and morphological evolution. However, there are too many complex physical processes involving in the interaction among hydrodynamics, sediment transport and vegetation. Therefore, a flume study was carried out in this paper to study the effects of vegetation on hydrodynamics and sediment transport.

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