Back to Blog
Tidal basin6/28/2023 Tidal asymmetry seems to be much more sensitive to the depth of the channels than to the size of the intertidal area in this particular case. This trend has been set in motion by the inundations in the 16th century and the land reclamations since then have not been able to reverse these trends, but have probably only amplified the exporting trend. Basin area evolution Eastern ScheldtĪnalysis of these observations, supported by hydrodynamic and sediment transport models, led to the conclusion that the morphological evolution of the Eastern Scheldt basin was dominated by a sediment exporting trend, with a continuously increasing tidal prism and continuously deepening channels. Modelling of physical processes for schematized tidal basins representing the various historical situations showed that the large-scale inundations caused the basin to scour to greater depth. a storm surge inundated large areas in the landward part of the basin, and in the following four centuries local inhabitants reclaimed about as much land as was lost during that storm (see figure below). These developments and effects on the tidal basin due to the interventions are described below. T his in turn causes erosion of shoals and flats and sedimentation in the channels (see ‘Channel-shoal interaction’), and probably also the vanishing of sediment exchange (see ‘Sediment exchange’) between the basin and the ebb-tidal delta. After construction of the storm surge barrier (1983-1986) a decrease of tidal currents occur, resulting in a decrease in sediment transport capacity. Due to the construction of back-barriers (1965 & 1969) the tidal prism increased even more, resulting in pushing the basin even more out of equilibrium than it already was. These have not been able to reverse the trend, but have probably only amplified the exporting trend. The trend of continuously increasing of the tidal prism and continuously deepening of the channels has been set in motion by the inundations in the 16th century (large storm surge in 1530) and the land reclamation since then. The Eastern Scheldt tidal basin has changed drastically in the past five centuries under the influence of both human interventions and extreme events.
0 Comments
Read More
Leave a Reply. |