Estimating Alongshore Sediment Transport and the Nodal Point Location on the Delaware–Maryland Coast

An approach to estimating sediment transport along the Delaware–Maryland coast is described. Wave information study (second generation model, WISWAVE 2.0) hindcast frequency-direction spectra from 1980 to 1999 are used to generate a radiation stress-conserving angle for bringing offshore waves to breaking to estimate alongshore sediment transport. Using standard values for the coefficients in the United States Army Corps of Engineers’ Coastal Engineering Research Center (CERC) equation yields 20-year mean alongshore sediment transport rates between 470,942 and −517,088  m3 /year depending on alongshore location after shoaling waves to shore. Interannual variability is large with SDs between 95,078 and 241,313  m3 /year again depending on alongshore location. Alongshore sediment transport rate estimates are commensurate with past studies using WIS data but overpredict the typically cited value of ∼100,000  m3 /year near Indian River Inlet, Delaware based on sediment budget data by a factor of 3–4. This ove...

[1]  Nathaniel S. Pearre,et al.  Quantifying Seasonal Shoreline Variability at Rehoboth Beach, Delaware, Using Automated Imaging Techniques , 2009 .

[2]  F. Feddersen Effect of wave directional spread on the radiation stress: comparing theory and observations , 2004 .

[3]  J. Andrew G. Cooper,et al.  Longshore Transport Volumes: A Critical View , 2002, Journal of Coastal Research.

[4]  R. Dalrymple,et al.  Coastal Processes with Engineering Applications , 2001 .

[5]  Steve Elgar,et al.  Modeling the alongshore current on barred beaches , 2001 .

[6]  S. Elgar,et al.  Wave transformation across the inner surf zone , 1996 .

[7]  Leo H. Holthuijsen,et al.  A Method for the Routine Analysis of Pitch-and-Roll Buoy Wave Data , 1988 .

[8]  Edward B. Thornton,et al.  Surf Zone Longshore Currents and Random Waves: Field Data and Models , 1986 .

[9]  Robert E. Jensen,et al.  Methodology for the Calculation of a Shallow-Water Wave Climate. , 1983 .

[10]  Edward B. Thornton,et al.  Energy saturation and phase speeds measured on a natural beach , 1982 .

[11]  Hajime Igarashi,et al.  FIELD EXPERIMENTS ON LONGSHORE SAND TRANSPORT IN THE SURF ZONE , 1982 .

[12]  R. Seymour,et al.  A compact representation of ocean wave directionality , 1981 .

[13]  D. Inman,et al.  Longshore sand transport on beaches , 1970 .

[14]  J. M. Caldwell Wave action and sand movement near Anaheim Bay, California , 1956 .

[15]  R. Dalrymple,et al.  A quantitative approach to Delaware's nodal point. , 1986 .

[16]  R. Dalrymple,et al.  A coastal engineering study of Indian RiverJInlet, Delaware. , 1977 .