Observations and modelling of shoreface nourishment behaviour

Huisman, B.J.A.; Walstra, Dirk Jan R.; Radermacher, Max; de Schipper, M.A.; Ruessink, B. Gerben

doi:10.3390/jmse7030059

Observations and modelling of shoreface nourishment behaviour

Title

Observations and modelling of shoreface nourishment behaviour

Author

Huisman, B.J.A. (TU Delft Coastal Engineering; Deltares)
Walstra, Dirk Jan R. (Deltares)
Radermacher, Max (H-max)
de Schipper, M.A. (TU Delft Coastal Engineering)
Ruessink, B. Gerben (Universiteit Utrecht)

Date

2019

Abstract

Shoreface nourishments are commonly applied for coastal maintenance, but their behaviour is not well understood. Bathymetric data of 19 shoreface nourishments located at alongshore uniform sections of the Dutch coast were therefore analyzed and used to validate an efficient method for predicting the erosion of shoreface nourishments. Data shows that considerable cross-shore profile change takes place at a shoreface nourishment, while an impact at the adjacent coast is hard to distinguish. The considered shoreface nourishments provide a long-term (3 to ~30 years) cross-shore supply of sediment to the beach, but with small impact on the local shoreline shape. An efficient modelling approach is presented using a lookup table filled with computed initial erosion-sedimentation rates for a range of potential environmental conditions at a single post-construction bathymetry. Cross-shore transport contributed the majority of the losses from the initial nourishment region. This transport was driven partly by water-level setup driven currents (e.g., rip currents) and increased velocity asymmetry of the waves due to the geometrical change at the shoreface nourishment. Most erosion of the nourishment takes place during energetic wave conditions (Hm0 ≥ 3 m) as milder waves are propagated over the nourishment without breaking. A data-model comparison shows that this approach can be used to accurately assess the erosion rates of shoreface nourishments in the first years after construction.

Subject

Erosion
Modelling
Morphology
Sand bar
Shoreface nourishment

To reference this document use:

http://resolver.tudelft.nl/uuid:e6e264d2-f32a-4bbd-9bda-16430d9f5171

DOI

https://doi.org/10.3390/jmse7030059

ISSN

2077-1312

Source

Journal of Marine Science and Engineering, 7 (3)

Part of collection

Institutional Repository