Wave Overtopping and Overwash of Dunes
Publication: Journal of Waterway, Port, Coastal, and Ocean Engineering
Volume 137, Issue 1
Abstract
Wave-induced overwash of sand dunes may cause rapid profile changes and possible dune destruction, thus increasing the flood risk landward of dunes. Accurate modeling of the wave overwash processes is therefore essential in predicting dune profile evolution during overwash events. However, available field and laboratory data are very limited. We measured dune profile evolution and overwash transport rates for three tests with different initial dune geometries in front of a low-crested vertical wall exposed to the same wave conditions in a wave flume. In all three tests, the transition from minor to major overwash occurred rapidly but the resilience of the dune against destruction depended on its initial geometry. During minor overwash, offshore sediment transport caused most of the dune crest lowering. These tests are used to assess a numerical model for wave overtopping and overwash of a dune. The numerical model is shown to be in agreement with the measurements of the free surface elevations, fluid velocities, and dune profiles. However, beach erosion in front of the exposed wall is underpredicted.
Get full access to this article
View all available purchase options and get full access to this article.
Acknowledgments
This study was supported by the U.S. Army Engineer Research and Development Center under Contract No. UNSPECIFIEDW912BU-09-C-0023. Permission to publish this paper was granted by the Office, Chief of Engineers, U.S. Army Corps of Engineers.
References
Boers, M. (1996). “Simulation of a surf zone with a barred beach. Part 1: Wave heights and wave breaking.” Communication on Hydraulic and Geotechnical Engineering, Rep. No. 96-5, Delft Univ. of Technology, Delft, The Netherlands.
Dolan, R., and Godfrey, P. (1973). “Effects of hurricane Ginger on barrier islands of North Carolina.” Geol. Soc. Am. Bull., 84, 1329–1334.
Donnelly, C., Kraus, N., and Larson, M. (2006). “State of knowledge on measurement and modeling of coastal overwash.” J. Coastal Res., 22(4), 965–991.
Figlus, J., Kobayashi, N., Gralher, C., and Iranzo, V. (2009). “Experimental and numerical study on the transition from minor to major wave overwash of dunes.” Research Rep. No. CACR-09-04, Center for Applied Coastal Research, Univ. of Delaware, Newark, Del.
Judge, E. K., Overton, M. F., and Fisher, J. S. (2003). “Vulnerability indicators for coastal dunes.” J. Waterway, Port, Coastal, Ocean Eng., 129(6), 270–278.
Kobayashi, N., Buck, M., Payo, A., and Johnson, B. D. (2009). “Berm and dune erosion during a storm.” J. Waterway, Port, Coastal, Ocean Eng., 135(1), 1–10.
Kobayashi, N., Farhadzadeh, A., Melby, J. A., Johnson, B. D., and Gravens, M. (2010). “Wave overtopping of levees and overwash of dunes.” J. Coastal Res., 26(5), 888–900.
Kobayashi, N., Herrman, M. N., Johnson, B. D., and Orzech, M. D. (1998). “Probability distribution of surface elevation in surf and swash zones.” J. Waterway, Port, Coastal, Ocean Eng., 124(3), 99–107.
Kobayashi, N., Tega, Y., and Hancock, M. W. (1996). “Wave reflection and overwash of dunes.” J. Waterway, Port, Coastal, Ocean Eng., 122(3), 150–153.
Kraus, N. C., and McDougal, W. G. (1996). “The effects of seawalls on the beach. Part 1: An updated literature review.” J. Coastal Res., 12(3), 691–701.
Sallenger, A. H. (2000). “Storm impact scale for barrier islands.” J. Coastal Res., 16(3), 890–895.
U.S. Army Engineer Research and Development Center. (2003). Coastal engineering manual. Part V, Coastal and Hydraulics Lab., Vicksburg, Miss.
Wamsley, T. V., Kraus, N. C., Larson, M., Hanson, H., and Connell, K. (2006). “Coastal barrier breaching: Comparison of physical and numerical models.” Proc., 30th Coastal Engineering Conf., World Scientific, Singapore, 2818–2828.
Wise, R. A., Smith, S. J., and Larson, M. (1996). “SBEACH: Numerical model for simulating storm-induced beach change. Report 4: Cross-shore transport under random waves and model validation with SUPERTANK and field data.” Technical Rep. No. CECR-89-9, U.S. Army Engineer Waterways Experiment Station, Vicksburg, Miss.
Information & Authors
Information
Published In
Journal of Waterway, Port, Coastal, and Ocean Engineering
Volume 137 • Issue 1 • January 2011
Pages: 26 - 33
Copyright
© 2011 ASCE.
History
Received: Oct 20, 2009
Accepted: May 27, 2010
Published online: Jun 9, 2010
Published in print: Jan 2011
Authors
Metrics & Citations
Metrics
Citations
Download citation
If you have the appropriate software installed, you can download article citation data to the citation manager of your choice. Simply select your manager software from the list below and click Download.