Pilot Project Sand Groynes Delfland Coast

Pilot Project Sand Groynes Delfland Coast

Hoekstra, R.
Walstra, D.J.R.
Swinkels, C.S.

Civil Engineering and Geosciences

Hydraulic Engineering

2012-12-31

In October and November 2009 a pilot project has been executed at the Delfland Coast in the Netherlands, constructing three small sandy headlands called Sand Groynes. Sand Groynes are nourished from the shore in seaward direction and anticipated to redistribute in the alongshore due to the impact of waves and currents to create the sediment buffer in the upper shoreface. The results presented in this paper intend to contribute to the assessment of Sand Groynes as a commonly applied nourishment method to maintain sandy coastlines. The morphological evolution of the Sand Groynes has been monitored by regularly conducting bathymetry surveys, resulting in a series of available bathymetry surveys. It is observed that the Sand Groynes have been redistributed in the alongshore, mainly in northward direction driven by dominant southwesterly wave conditions. Furthermore, data analysis suggests that Sand Groynes have a trapping capacity for alongshore supplied sand originating from upstream located Sand Groynes. A Delft3D numerical model has been set up to verify whether the morphological evolution of Sand Groynes can be properly hindcasted. Although the model has been set up in 2DH mode, hindcast results show good agreement with the morphological evolution of Sand Groynes based on field data. Trends of alongshore redistribution of Sand Groynes are well reproduced. Still the model performance could be improved, for instance by implementation of 3D velocity patterns and by a more accurate schematization of sediment characteristics.

Sand Groyne, Delfland Coast, sand nourishment, sediment transport, Delft3D

http://resolver.tudelft.nl/uuid:fb576e4c-1055-4747-a91a-031d87c1a190

Coastal Engineering Research Council

2156-1028

ICCE 2012: Proceedings of the 33rd International Conference on Coastal Engineering, Santander, Spain, 1-6 July 2012

Institutional Repository

conference paper

(c) 2012 The Authors