Atlantic States Marine Fisheries Commission Beach Nourishment: A Review of the Biological and Physical Impacts ASMFC Habitat Management Series # 7 November 2002 Atlantic States Marine Fisheries Commission 1444 Eye Street NW, Sixth Floor Washington DC 20005 ASMFC Habitat Management Series # 7 Beach Nourishment: A Review of the Biological and Physical Impacts by Karen Greene Atlantic States Marine Fisheries Commission Atlantic States Marine Fisheries Commission 1444 Eye Street, NW, Sixth Floor Washington, DC 20005 i ACKNOWLEDGMENTS The assistance of Carrie Selberg (Atlantic States Marine Fisheries Commission) was instrumental in the preparation of this report. Her ongoing guidance and editorial comments were invaluable. Jennifer Lowery (National Marine Fisheries Service Silver Spring, MD) contributed significantly by gathering scientific reports and periodicals, and her help is greatly appreciated. Special thanks to Mike Street (NC Division of Marine Fisheries) and Bob Van Dolah (SC Marine Resource Division) for reviewing this report in its entirety and providing substantial edits and direction. This report was reviewed and approved by the ASMFC Habitat Committee (Bill Goldsborough, Chesapeake Bay Foundation, Chair; Gail Wippelhause, ME Department of Marine Resources; Paul Caruso, MA Division of Marine Fisheries; Chris Powell, RI Department of Environmental Management; Lance Stewart, University of Connecticut; Karen Chytalo, New York State Department of Environmental Conservation; Bruce Freeman, NJ Department of Environmental Protection; Tom Fote, Commissioner from NJ; Jeff Tinsman, DE Division of Fish and Wildlife; Robert Grabb, VA Marine Resources Commission; Mike Street, NC Division of Marine Fisheries; Melvin Shepard; Rob Dunlap and Bob Van Dolah, SC Department of Natural Resources; Phil Flournoy, GA Department of Natural Resources; Ken Haddad, FL Fish and Wildlife Conservation Commission; Dianne Stephan and Tom Bigford, National Marine Fisheries Service, Wilson Laney and Jed Brown, U.S. Fish and Wildlife Service). The contribution of additional literature and personal insight from Tracy Rice (U.S. Fish and Wildlife Service Raleigh, NC), Charles Peterson (UNC Institute of Marine Sciences), Ken Lindeman (Environmental Defense Fund), and Orrin Pilkey (Duke University Division of Earth and Ocean Sciences) is gratefully acknowledged. Other individuals who reviewed this report and provided contributions include Nancy Jackson (New Jersey Institute of Technology), Keith Mille (FL Fish and Wildlife Commission), Tony Watkinson (VA Marine Resources Commission), and Frank Steimle (National Marine Fisheries Service Sandy Hook). This is a publication of the Atlantic States Marine Fisheries Commission pursuant to National Oceanic and Atmospheric Administration cooperative agreement award number NA17FG2205, National Marine Fisheries Service purchase order number DG133F-02-SE-0736, and Wallop Breaux grant agreement number A-4-1. ii TABLE OF CONTENTS ACKNOWLEDGMENTS_______________________________________________________ ii INTRODUCTION ____________________________________________________________ 1 MANAGING SHORELINE EROSION ___________________________________________ 2 Hard Stabilization _________________________________________________________________ 3 Non-Structural Alternatives_________________________________________________________ 4 Soft Stabilization __________________________________________________________________ 4 BEACH NOURISHMENT _____________________________________________________ 4 Dredging and Emplacing Sand ______________________________________________________ 6 Federally Funded Beach Nourishment Projects_________________________________________ 8 State Beach Nourishment Policies ____________________________________________________ 8 ENVIRONMENTAL IMPACTS _________________________________________________ 9 Cumulative Impacts ______________________________________________________________ 10 THE MINE SITE ________________________________________________________________ 12 Sediment_______________________________________________________________________________12 Physical Habitat _________________________________________________________________________14 Benthos________________________________________________________________________________15 Ridges and Swales _______________________________________________________________________18 Turbidity_______________________________________________________________________________18 Fisheries _______________________________________________________________________________19 Marine Mammals and Sea Turtles ___________________________________________________________21 THE TARGET BEACH ___________________________________________________________ 21 Sediment_______________________________________________________________________________22 Beach Bulldozing ______________________________________________________________________23 Benthos________________________________________________________________________________23 Emerita talpoida, Donax spp., and Ocypode spp.________________________________________________25 Beach Bulldozing ______________________________________________________________________27 Turbidity_______________________________________________________________________________28 Sea Turtles _____________________________________________________________________________30 Shorebirds______________________________________________________________________________31 Fisheries _______________________________________________________________________________31 Physical Habitat _________________________________________________________________________34 RESEARCH NEEDS_________________________________________________________ 36 Mine site ________________________________________________________________________ 37 Target Beach ____________________________________________________________________ 37 Adjacent Communities ____________________________________________________________ 39 GENERAL RECOMMENDATIONS ____________________________________________ 39 iii Turbidity _______________________________________________________________________ 40 Research Design and the United States Army Corps of Engineers ________________________ 41 CONCLUSION______________________________________________________________ 41 Bibliography________________________________________________________________ 44 Appendix A The Federal Beach Nourishment Process ____________________________ 70 Appendix B State Beach Nourishment Programs ________________________________ 77 Appendix C Fish Habitat ___________________________________________________ 118 iv INTRODUCTION Many beaches along the east coast of the United States are eroding, which threatens habitat, property, public infrastructure, and the tourist industry. Loss of sand can be attributed to natural factors such as storms, sea level changes, waves, currents, tides, wind, bathymetry, shoreline geology, sand supply and quality, and sand movement among dunes, beach, and offshore bars (Bird, 1983; NRC, 1990a). Shortages of sediment can also arise from man-made activities including construction of harbors, groins, jetties, and seawalls; shoreline development; dredging of tidal inlets; damming of rivers; and beach nourishment (London et al., 1981; Kana, 1988; NRC, 1990). Of all the forces that contribute to erosion, sea level rise is one of the major global concerns that will likely affect coastlines throughout the world in the coming years. Sea level is estimated to rise approximately 20 cm by the year 2050 (IPCC, 1996), which translates to an average of 1 meter of shoreline erosion per year (Leatherman et al., 2000). Some sources estimate the total U.S. shoreline subjected to erosion will be close to 80%, while others put the total at 100%, if stable or accreting shorelines are considered short-lived (Pilkey and Dixon, 1996). Some areas will experience greater impacts than others from sea-level rise, due to local geologic rise or fall of land areas relative to global sea level changes, local geological structures, and other factors. Coastlines move in response to many of the natural forces that simultaneously act upon them in an attempt to maintain equilibrium (Williams, 2001). Shoreline erosion can lead to a loss of habitat for sea turtles, birds, fish, plants, and a host of other organisms that use the beach during some portion, or all, of their life cycle. Along barrier islands, shoreline erosion could more accurately be termed “shoreline retreat,” because the beach is not actually eroding, but is moving landward in response to a rising sea level (Pilkey, 1996). This concept applies when the barrier island is able to retreat, and there is simultaneous sand accretion on the sound side of the island. In situations where the shorefront is unable to migrate landward, the term “shoreline erosion” would be accurate. In the Mid-Atlantic Region, barrier beaches migrate in a north-south direction (Dixon and Pilkey, 1991). Erosion is also problematic when there are structures that lie in harm’s way, which require protection against impending waves and sea level rise (Pilkey, 1996). Man has attempted to halt retreating shorelines for decades in an effort to save these structures. The first documented beach nourishment project took place in this country during 1922-1923 at Coney Island, New York (Farley, 1923). During the 1930’s, the federal government became involved in dune construction activities along the Outer Banks of North Carolina. It was not until 1962, following the devastating