Nearshore Impacts of Dredging for Beach Nourishment
Publication: Journal of Waterway, Port, Coastal, and Ocean Engineering
Volume 130, Issue 6
Abstract
A methodology is presented for predicting the impacts of nearshore dredging on shoreline change, using numerical models for waves, currents, and shoreline change. The dredge pit, outside of the surf zone, was assumed to be steady state, but alters waves reaching the surf zone. The methodology accounts for the transformation of directional wave energy spectra due to spatial gradients in both mean currents and bathymetry, wind inputs, and energy dissipation via several mechanisms. The wave transformation model SWAN (Simulating Waves Nearshore) was used to simulate waves at Folly Island, S.C., which served as the test case. Wave model results were validated using short-term field measurements at three locations. Longer-term (1 year) simulations were driven using hindcast wave and wind data. Velocity fields and tidal stages were simulated using the hydrodynamic model Environmental Fluid Dynamics Code in two-dimensional mode, after calibrating with field measurements. Wave model results were used to estimate longshore sediment transport and shoreline change due to longshore gradients of the longshore sediment transport rate. Empirical sediment transport coefficients were chosen to match model results to measured beach volume changes derived from beach profile data. The calibrated model was then used to predict impacts of dredging on long-term shoreline change. Results reproduced observed trends of erosion and accretion along approximately 90% of the shoreline.
Get full access to this article
View all available purchase options and get full access to this article.
References
1.
Booij, N., Ris, R. C., and Holthuijsen, L. H. (1999). “A third-generation wave model for coastal regions, 1. Model description and validation.” J. Geophys. Res., 104(C4), 7649–7666.
2.
Brooks, R.M., and Brandon, W.A. (1995). “Hindcast wave information for the U.S. Atlantic Coast: Update 1976-1993 with hurricanes.” WIS Rep. 33, U.S. Army Corps of Engineers, Waterways Experiment Station, Vicksburg, Miss.
3.
Byrnes, M. R., Hammer, R. M., Thibaut, T. D., and Snyder, D. B. (2004). “Physical and biological effects of sand mining offshore Alabama, USA.” J. Coastal Res., 20(1), 6–24.
4.
Combe, A.J., and Soileau, C.W. (1987). “Behavior of man-made beach and dune, Grande Isle, Louisiana.” Proc., Coastal Sediments ’87, v.II, ASCE, Reston, Va., 1232–1242.
6.
Dean, R.G., and Dalrymple, R.A. (2002). Coastal processes with engineering applications, Cambridge University Press, Cambridge, U.K.
7.
Demir, H. (2002). “Effects of dredge holes on the shoreline change in the Black Sea.” MS thesis, Civil Engineering Dept., Boğaziçi Univ., Istanbul, Turkey.
8.
Ebersole, B.A., Neilans, P.J., and Dowd, M.W. (1996). “Beach-fill performance at Folly Beach, South Carolina (1 year after construction) and evaluation of design methods.” Shore and Beach, (1), 11–26.
9.
Edge, B. L., and Dean, R. G. (1990). Folly Beach-Report, presented to Charleston County Committee to restore Folly Beach, Charleston, S.C.
10.
Edge, B.L., Dowd, M., Dean, R.G., and Johnson, P. (1994). “Reconstruction of Folly Beach.” Proc. 24th Intl. Conf. on Coastal Eng., v.3, ASCE, Reston, Va., 3491–3506.
11.
Fehrenbacher, F. (2003). “Predicting shoreline change due to nearshore dredging at Folly Island, South Carolina.” MS thesis, School of Civil and Environmental Engineering, Georgia Institute of Technology, Savannah, Ga.
12.
Gayes, P.T., Baldwin, W., Eiser, W., van Dolah, R., Jutte, P.C., and Hansen, M. (2001). “Long-term beach monitoring at Folly Beach, South Carolina and other recently renourished beaches along the South Carolina Coast.” Proc., 2001 National Conf. on Beach Preservation Technology, compiled by L. Tait, Tallahassee, Fla. 81–96.
13.
Hamrick, J.M. (1992). “A three-dimensional environmental fluid dynamics computer code: Theoretical and computational aspects.” Special Rep. 317, Virginia Institute of Marine Science, The College of William and Mary, Gloucester Point, Va.
14.
Hamrick, J.M. (1996). “User’s manual for the environmental fluid dynamics computer code.” Special Rep. No. 331, Virginia Institute of Marine Science, The College of William and Mary, Gloucester Point, Va.
15.
Hasselmann, K., et al. (1973). “Measurements of wind-wave growth and swell decay during the Joint North Sea Wave Project (JONSWAP).” Deutsch Hydrograph, Zeit., Erganzung-self Reihe, A8 (12).
16.
Hobbs, C.H., III (1998). “Environmental studies relative to potential sand mining in the vicinity of Virginia Beach, Virginia.” Final report to the Minerals Management Service, Virginia Institute of Marine Science, The College of William and Mary, Gloucester Point, Va.
17.
Jin, X. (2001). “Nearshore wave and current measurements and prediction: Folly Beach, South Carolina.” MS thesis, Dept. of Civil Eng., Clemson Univ., Clemson, S.C.
18.
Kana, T.W. (2002). “Analysis of potential downdrift impacts.” Folly Beach County Park, Stabilization Project, Final Report, Coastal Science and Engineering, Columbia, S.C.
19.
Luettich, R.A., Westerink, J.J., and Scheffner, N.W. (1992). “ADCIRC: An advanced three-dimensional circulation model for shelves, coasts and estuaries, Report 1: Theory and methodology of ADCIRC-2DDI and ADCIRC-DL.” Technical Rep. DRP-92-6, U.S. Army Engineer Waterways Experiment Station, Vicksburg, Miss.
20.
Maa, J. P. Y., and Hobbs, C. H. (1998). “Physical impacts of waves on adjacent coasts resulting from dredging at Sandbridge Shoal, Virginia.” J. Coastal Res., 14(2), 525–536.
21.
Maa, J. P. Y., Hobbs, C. H., Kim, S. C., and Wei, E. (2004). “Potential impacts of sand mining offshore of Maryland and Delaware: Part 1—impacts on physical oceanographic processes.” J. Coastal Res., 20(1), 44–60.
22.
Mitsuyasu, H., Suhaya, T., Mizuno, S., Ohkuso, M., Honda, T., and Rikiishi, K. (1975). “Observations of the directional spectrum of ocean waves using a cloverleaf buoy.” J. Phys. Oceanogr., 5, 750–760.
23.
Otay, E.N., Demir, H., Borekci, O.S., and Work, P.A. (2002). “Marine sand exploitation off the Turkish Black Sea coast.” Proc. Littoral’02, Porto, Portugal, 467–477.
24.
Ris, R. C., Holthuijsen, L. H., and Booij, N. (1999). “A third-generation wave model for coastal regions, 2. Verification.” J. Geophys. Res., 104(C4), 7667–7681.
25.
Scheffner, N.W., and Carson, F.C. (2001). “Coast of South Carolina storm surge study. ”Final Report, ERDC/CHL TR-01-11, U.S. Army Corps of Engineers, Vicksburg, Miss.
26.
Schwab, W.C., Gayes, P.T., and Denny, J.F. (2002). “Preliminary interpretation of USGS geophysical survey off Folly Beach, SC: Sampling strategy for sand resource investigation.” U.S. Geological Survey Administrative Rep., 26 August 2002.
27.
Sharman, G., et al. (1998). “GEODAS: A hydro/bathy data management system.” Surv. Land Inf. Sys., 58(3), 141–146.
28.
Smagorinsky, J. (1963). “General circulation experiments with the primitive equations. Part I: The basic experiment.” Mon. Weather Rev., 91, 99–152.
29.
Stone, G. W., Pepper, D. A., Xu, J., and Zhang, X. (2004). “Ship shoal as a prospective borrow site for barrier island restoration, coastal south-central Louisiana, USA: Numerical wave modeling and field measurements of hydrodynamics and sediment transport.” J. Coastal Res., 20(1), 70–88.
30.
Stone, G.W., and Xu, J. (1996). “Wave climate modeling and evaluation relative to sand mining on Ship Shoal, Offshore Louisiana, for coastal and barrier island restoration.” Final Rep., October, 1996, prepared for Minerals Management Service, U.S. Dept. of Interior, by Coastal Morphodynamics Laboratory, Dept. of Geography and Anthropology, Louisiana State Univ., Baton Rouge, La.
31.
U.S. Army Corps of Engineers. ( 1984). Shore Protection Manual, Coastal Engineering Research Center, Vicksburg, Miss.
32.
U.S. Army Corps of Engineers, Charleston District. (1991). Folly Beach, South Carolina Shore Protection Project, Vol. I.
33.
U.S. Army Corps of Engineers, Waterways Experiment Station. (2001). “Coastal Engineering Manual.” EC 1110-2-1100, U.S. Government Printing Office, Washington, D.C.
34.
Work, P.A., Fehrenbacher, F., Voulgaris, G., and Chen, J. (2003). “Nearshore dredging impacts, Folly Island, SC, USA.” Proc. Coastal Sediments’03, St. Petersburg, Fla.
35.
Work, P.A., Voulgaris, G., and Fehrenbacher, F. (2002). “Shoreline change due to nearshore dredging.” Proc., Littoral ’02, Porto, Portugal.
Information & Authors
Information
Published In
Journal of Waterway, Port, Coastal, and Ocean Engineering
Volume 130 • Issue 6 • November 2004
Pages: 303 - 311
Copyright
Copyright © 2004 ASCE.
History
Published online: Oct 15, 2004
Published in print: Nov 2004
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.