Morphodynamics of the Ameland Bornrif: An analogue for the Sand Engine

Morphodynamics of the Ameland Bornrif: An analogue for the Sand Engine

Achete, F.M.

Luijendijk, A. (mentor)
Tonnon, P.K. (mentor)
Stive, M.J.F. (mentor)
Schipper, M.A. (mentor)

Civil Engineering and Geosciences

Hydraulic Engineering

CoMEM - Coastal and Marine Engineering and Management

2011-06-23

The objective of this work is the understanding of the development and possible impacts of the Sand Engine via a possible analogy with the Bornrif morphodynamics. The Sand Engine is the pilot project for a new nourishment technology (the mega nourishment), which consists of nourishing a huge amount of sand at once and let the nature spread it. For the pilot project Sand Engine Delfland 21 million meter3 of sand are being placed. The evolution and impacts of such a project is widely unknow due to the unique character of the intervention. However, the Amelander Bornrif exhibits a similar shape to the one designed for the Sand Engine, so the understanding of a natural phenomenon may give knowhow to apply and monitor the Sand Engine project. The Bornrif analysis was based on a data analysis that resulted in a conceptual model, where the main features and process were defined. Another aspect derived from the data analysis was the comparison with a wave shape parameter, the breaking intensity, that describes the lagoon shape as well as the reaching of the hook. Applying the knowledge acquired from the data analysis a process based model, Delft3D, was used to numerically simulate the Bornrif.The experiments were divided in two groups: the short term, where the hindcast of 5 years of development was performed even as a sensitivity analysis. For the short-term it is concluded that the main forcings are the waves. The second group of simulations, covered the longterm hindcast, where the inclusion of cohesive sediment had a high impact on the overall Bornrif developement. The Bornrif development is reproduced only applying a wave climatology, not including individual storms. Therefore, some findings can be transferred from the Bornrif to the Sand Engine as the period of the hook evolution, taking approximately 5 years; the possibility of erosion of the mainland due to a channel formation; and the reduction of the morphological change after the hook merges with the mainland.

Morphodynamics
Delft3D
Ameland Bornrif
vortex ratio

http://resolver.tudelft.nl/uuid:76aabdcf-c3da-4a45-9720-39d2702e5c29

Student theses

master thesis

(c) 2011 Achete, F.M.