comprehensive considering that, at least in shallow water, measurements were made with 

 sounding poles or lead lines (Shalowitz 1964). Figure 7 shows the 1933 survey lines, and 

 Figure 8 is the same data contoured. In these figures, a modern shoreline has been included for 

 reference, but the reader must remember that Shinnecock Inlet was not open then. This 

 shoreline, also shown in subsequent figures, is based on 1990's National Oceanic and 

 Atmospheric Administraction (NOAA) charts. Notes on these and other data sources are listed 

 in Appendix B. 



In 1933, the Atlantic shoreline was almost straight and showed no obvious evidence of older 

 inlets. From the shore to about 7 m, a series of bars is evident in the contoured bathymetry. 

 Deeper than 7 m, offshore contours are reasonably straight and parallel. 



1949 Morphology 



Shinnecock Inlet and its ebb and flood shoals were surveyed by USACE in July and August 

 of 1949. By this time, State of New York, Suffolk County, and the Town of Southampton had 

 built a 240-m stone revetment on the west side by the inlet. Only 1 1 years after the inlet was 

 breached, a broad, oval-shaped ebb shoal had already formed (Figure 9). It extended about 

 1,500 m to the west, 400 m offshore, and at least 600 m to the east of the inlet's mouth (the 

 survey did not extend far enough east to cover the full shoal). The top of the shoal was at a depth 

 of about -3 m, and the bar front dropped steeply from -3 m to the seafloor beyond -6 m. In the 

 flood shoal, two dredged channels are evident, one extending from the landward end of the inlet 

 to the west and another extending northeast and then north. 



1994 Morphology 



In June and August of 1994, Shinnecock Inlet and the ocean coast between Moriches and 

 Shinnecock Inlets was surveyed with the SHOALS 1 helicopter-borne hydrographic LEDAR 

 survey system. The tremendous data density recorded by the SHOALS system provided 

 unprecedented seafloor detail. Unfortunately, the 1994 surveys were not flown far enough 

 seaward to cover the entire ebb shoal. The contoured data (Figure 10) show that the ebb shoal 

 attached to the downdrift shore about 2.4 km west of the west jetty. The shoal platform had 

 depths about 3 m below mllw. The deep area seaward of the jetties was the deposition basin 

 from which 363,000 m 3 (475,000 yd 3 ) of sand was removed in early 1993. Because coverage did 

 not include the edge of the ebb shoal, these 1994 data were not used for volumetric comparisons. 



Scanning Hydrographic Operational Airborne LIDAR Survey (SHOALS) is a USACE- developed system using a helicopter- 

 based laser to conduct hydrographic surveys (Lillycrop, Parson, and Irish 1996). 



Chapter 2 Geologic Setting and Morphologic Development 1 3 



