Table 27 

 Nantucket Harbor Jetties 

 Nantucket Island, Mass. 



Date(s) Construction and Rehabilitation History 



1881- The east and west rubble-mound jetties were constructed to lengths of 

 1907 6,987 and 4,955 ft, respectively. The jetties converged to a 



distance of approximately 1,000 ft, with the east Jetty extending 

 800 ft seaward of the west jetty (Figure 30, plan view). Crown 

 elevations were typically +5 ft mlw, side slopes 1 V : 1 H , and crown 

 widths 4 and 6 ft on the west and east jetties, respectively. 

 Approximately 63,000 and 59,000 tons of stone were used in the east 

 and west jetties, respectively. 



1917 The outer end of the east Jetty was reconstructed for the purpose of 

 mounting a navigation light. A total of 1,790 tons of stone was used 

 for a total cost of $5,300. 



1926 East jetty repairs were made on all but the outer 300 ft of its 

 length. The total repair cost was $41,600. 



1936- East jetty repairs were made using 15,900 tons of stone at a total 

 1937 cost of $56,900. 



1962- About 4,400 lin ft of the east Jetty was rehabilitated. The repair 

 1963 sections were located from 5+50 to 6+00 and from 8+34 to 52+00. The 

 jetty's seaward end was at approximately 52+75. The design crown 

 width and side slopes were 6 ft and 1V:1.5H, respectively. The land- 

 ward and seaward sections were raised to +5 and +3 ft mlw, respec- 

 tively. Minimum stone size was 1.5 tons, with 75 percent of the 

 total stone quantity in pieces weighing a minimum of 2 tons. Prior 

 to repairs, the seaward section had typical crown elevations between 

 +1 and -2 ft mlw. The repairs required 15,100 tons of stone for a 

 total cost of $181,000. 



1967- Visual inspections indicated the east jetty was in fair condition 

 1977 with some displacement of stone noted. The west jetty was in poor 

 condition, with most of the structure below mhw (+3 ft mlw). 



1981 Yearly visual inspections indicated the jetties were in good 

 condition. 



1986 Present conditions of the jetties are not known. 



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