Table 13 



Shinnecock Inlet Jetties 



Tiana Beach and Hampton Beach, New York 



New York District 



Date(s) Construction and Rehabilitation History 



1953 Local interests constructed two jetties for inlet stabilization at 

 lengths of 1,363 ft east (Figure 17) and 850 ft west. The cost of 

 construction was $846,210 east and $376,000 west. The design geome- 

 try of both jetties consisted of +9.0-ft mlw crest elevations, 12.0- 

 ft crown widths, and 1 V : 1 . 5H side slopes. The jetties were con- 

 structed of one layer capstone, 4.0- to 10- ton stone on the landward 

 1,163 ft of the east jetty, and 6.0- to 12- ton stone elsewhere. 

 Core stone used on the east jetty was 5.0 lb to 1.0 ton on the land- 

 ward 1,163 ft and 5.0 lb to 2.0 tons elsewhere. Core stone used on 

 the west jetty was 50 lb to 1.0 ton. A 2.0-ft-thick blanket and 

 apron stone were placed using 5.0- to 500-lb stone. 



1954 Local interests extended the west jetty 96 ft (Figure 17) at a cost 

 of $166,230. The extension was built at the same elevation and width 

 as the original jetty. Side slopes were 1V:2H. Capstone was 6.0 to 

 12 tons, covering 10-lb to 2.0-ton core stone resting on a 2.0-ft- 

 thick blanket and apron, consisting of 50- to 500-lb stone. 



1956 A survey revealed that the east jetty had suffered severe damage. 

 Capstones and slope stones had slipped and were disarranged in nu- 

 merous spots. Core stones were washed out in several places. Cap- 

 stones and core stones were washed out in four locations totaling 

 150 ft. The outer 250 ft of the jetty was partly washed out. Beach 

 and dunes adjacent to the jetty eroded, and waves rode over the dunes 

 and flanked the jetty. The west jetty was in fair condition with 

 minor slips and disarrangement in five spots. The inlet was in a 

 shoal condition. Most of the damage was due to a hurricane in 1954. 



1982 The west jetty was reconstructed by resetting cap stones to original 

 design geometry over 170 ft. A 1 ,470-ft-long pile crib revetment on 

 the north end of the west jetty was replaced by a rubble-mound jetty. 

 (Figure 18). 



1985 A survey revealed that the reconstructed portion of the west jetty 

 was in good condition. The seaward 200 ft of the west jetty had 

 unraveled and capstones were scattered. The west jetty head had not 

 maintained design configuration. Stones on the inlet side of the 

 east jetty had sloughed in some sections, but stones on the beach 

 side had retained their original position. Two areas on the northern 

 end were completely deteriorated. Erosion of sand caused undermining 

 of the east jetty with continual loss of sand undermining it further. 



(Continued) 



32 



