A numerical model investigation of the formation and persistence of an erosion hotspot

By: , and 

Links

Abstract

A Delft3D-SWAN coupled flow and wave model was constructed for the San Francisco Bight with high-resolution at 7 km-long Ocean Beach, a high-energy beach located immediately south of the Golden Gate, the sole entrance to San Francisco Bay. The model was used to investigate tidal and wave-induced flows, basic forcing terms, and potential sediment transport in an area in the southern portion of Ocean Beach that has eroded significantly over the last several decades. The model predicted flow patterns that were favorable for sediment removal from the area and net erosion from the surf-zone. Analysis of the forcing terms driving surf-zone flows revealed that wave refraction over an exposed wastewater outfall pipe between the 12 and 15 m isobaths introduces a perturbation in the wave field that results in erosion-causing flows. Modeled erosion agreed well with five years of topographic survey data from the area.

Study Area

Additional publication details

Publication type Conference Paper
Publication Subtype Conference Paper
Title A numerical model investigation of the formation and persistence of an erosion hotspot
DOI 10.1142/9789814355537_0134
Year Published 2011
Language English
Publisher World Scientific
Contributing office(s) Pacific Coastal and Marine Science Center
Description 14 p.
Larger Work Type Conference Paper
Larger Work Title The proceedings of the Coastal Sediments 2011
Conference Title 7th International Symposium on Coastal Engineering and Science of Coastal Sediment Processes
Conference Location Miami, Florida
Conference Date May 2-6, 2011
Country United States
State California
Other Geospatial Ocean Beach. San Francisco
Online Only (Y/N) N
Additional Online Files (Y/N) N