GEOMORPHOLOGY AND SEDIMENTS OF THE 

 INNER NEW YORK BIGHT CONTINENTAL SHELF 



by 



S. Jeffress Williams 



and 



David B. Duane 



I. INTRODUCTION 



1. Background. 



Ocean beaches and associated dunes provide a necessary and important buffer zone 

 between the sea and fragile coastal areas. At the same time they provide public recreation 

 areas for millions of people. The construction, improvement and periodic maintenance of 

 beaches and dunes by placement (nourishment) of suitable sand along the shoreline can be 

 an important means of counteracting coastal erosion by providing stability to shoreline 

 positions and permitting recreational facilities. (U.S. Army, Corps of Engineers, 1971.) 

 Beach nourishment techniques (Hall, 1952) have gained prominence in coastal engineering 

 largely as a result of the successful test program using a hopper dredge at Sea Dirt, New 

 Jersey in 1966 by the U.S. Army, Corps of Engineers (1967); and the successful completion 

 of the nourishment of Redondo Beach, California, in 1969 by a commercial operator under 

 contract to the Corps of Engineers. (Fisher, 1970.) The Redondo Beach project determined 

 that present technology is advanced enough to make sand and gravel on the shallow parts of 

 the shelves a presently exploitable resource (Duane, 1968) and economically competitive at 

 some locations with previous methods (truck haul and drag scoop) for sand transport and 

 beach construction. 



Plans for initial beach restoration and periodic renourishment usually involve large 

 volumes of suitable sand fill. In recent years it has become increasingly difficult to obtain 

 suitable sand from lagoons and wetlands or from inland sources in sufficient volumes and at 

 an economical cost for beach fill purposes. These difficulties are due in part to increased 

 land values, concern over environmental and ecological effects of removing such large 

 volumes of sand, diminution or depletion of previously used land sources, and inflated 

 transportation costs of moving the material from areas increasingly remote from final 

 destinations. Also, sedimentary material comprising the bottoms of lagoons, estuaries, and 

 bays is often fine-grained and rich in organics and is unsuitable for long-term effective 

 shoreline protection. While the loss of some fine silt material is to be expected as a newly 

 nourished beach attains a new state of equilibrium with the sea environment, it is possible to 

 minimize the losses through careful selection of the most suitable fill material. (Krumbein 

 and James, 1965.) 



