line with jet agitation rather than the conventional rigid ladder and 

 cutterhead. Dredges with a rigid ladder and cutterhead were used on beach 

 fills at Pompano Beach and Fort Pierce, Florida, where the borrow area was 

 offshore on the open ocean. 



Some hopper dredges are now available with pump-out capability. After 

 loading at the borrow site (normally offshore), the hopper dredge then moves 

 close to the fill site and pumps sand from the hoppers through a submerged 

 pipeline to the beach. This method is particularly applicable to sites where 

 the offshore borrow area is a considerable distance from the beach restoration 

 project. This method was tested successfully in 1966 at Sea Girt, New Jersey 

 (Mauriello, 1967; U.S. Army Engineer District, Philadelphia, 1967). As off- 

 shore borrow areas in the immediate vicinity of protective beach projects 

 become scarce, the use of hopper dredges may become more appropriate. 



The choice of borrow method depends on the location of the borrow source 

 and the availability of suitable equipment. Borrow sources in bays and 

 lagoons may become depleted, or unexploitable because of injurious ecological 

 effects. It is now necessary to place increased reliance on offshore sources. 

 CERC reports on the geomorphology, sediments, and structure of the Inner 

 Continental Shelf with the primary purpose of finding sand deposits suitable 

 for beach fill are summarized in Table 6-1. Hobson (1981) presents sediment 

 characteristics and beach-fill designs for 20 selected U.S. sites where the 

 use of offshore borrow sites has been suggested. Sand from offshore sources 

 is frequently of better quality for beach fill because it contains less fine- 

 grained sediments than lagoonal deposits. Equipment and techniques are 

 currently capable of exploiting offshore borrow sources only to a limited 

 extent; and as improved equipment becomes available, offshore borrow areas 

 will become even more important sources of beach-fill material. 



Table 6-1, 



CERC research reports on the geomorphology and sediments 

 of the Inner Continental Shelf. 



Region 



Reference 



Palm Beach to Miami, Florida 

 Cape Canaveral to 



Palm Beach, Florida 

 Chesapeake Bay Entrance 

 Cape Canaveral, Florida 

 New York Bight 

 North Eastern Florida Coast 

 Western Massachusetts Bay 

 Long Island Shores 

 Cape Fear Region, North Carolina 

 Delaware-Maryland Coast 

 Southeastern Lake Michigan 

 Galveston, Texas 

 Cape May, New Jersey 

 South Lake Erie, Ohio 

 Long Island Sound 

 Central New Jersey Coast 



Duane and Meisburger (1969) 

 Meisburger and Duane (1971) 



Meisburger (1972) 



Field and Duane (1974) 



Williams and Duane (1974) 



Meisburger and Field (1975) 



Meisburger (1976) 



Williams (1976) 



Meisburger (1977 and 1979) 



Field (1979) 



Meisburger, Williams, and Prins (1979) 



Williams, Prins, and Meisburger (1979) 



Meisburger and Williams (1980) 



Williams, et al. (1980) 



Williams (1981) 



Meisburger and Williams (1982) 



6-15 



