Table 18 



Fort Pierce Harbor Jetties 



Fort Pierce, Florida, SAJ 



Date(s) Construction and Rehabilitation History 



1922- Local interests constructed parallel jetties, each 400 ft long and 

 1929 spaced 600 ft apart, to protect a dredged channel 5 ft deep by 90 ft 

 wide. About 1925, seas eroded the north beach and flanked the north 

 jetty, leaving it 200 to 300 ft offshore. In 1926 local interests 

 started construction of another jetty 400 ft north of, and parallel 

 to, the south jetty. At the completion of these improvements in 

 1929, the north and south jetties were 2,300 ft and 1,600 ft, re- 

 spectively (Figure 31), and the channel between the jetties was 

 240 ft wide and had a controlling depth of 20 ft. The structures 

 were constructed of native coquina stone with 1V:1H side slopes 

 below, and 2V:1H slopes above -7 ft mlw. 



1931 The district engineer report states that the jetties had settled and 

 that wave action had created numerous gaps. 



1933- The jetties, at that time under Corps jurisdiction, were repaired 

 1934 using 4- to 10-ton granite stone (Figure 31, inset). Prior to the 

 repairs the existing side slopes were irregular but approximately 

 IV: 2H, and the alignment of each jetty was irregular. These irregu- 

 larities were corrected during the repairs. The existing crown 

 elevation of the jetties ranged from mlw to +6 ft mlw. On the north 

 jetty and outer 400 ft of the south jetty, old stone above -1 ft mlw 

 was removed and placed below this elevation. New stone was placed 

 along both jetties to a crown elevation of +6 ft mlw, a 10-ft crown 

 width, and IV: 2H side slopes. In addition, the south jetty was ex- 

 tended 420 ft, the crown elevation on the inner 320 ft sloped from 

 +6 ft mlw to -5 ft mlw, and the outer 100 ft consisted of a 3-ft- 

 thick by 40-ft-wide stone apron. The estimated quantities of old 

 rehandled stone and new stone were 7,500 cu yd and 38,000 tons, 

 respectively. The water depth at the end of the jetties was approx- 

 imately -10 ft mlw. The cost of the repair work was $246,000. 



1949 The annual report of the Chief of Engineers states, "both jetties 

 are in good condition." 



1985 Presently a 350-ft-wide by 27-ft-deep channel is maintained, running 

 adjacent to the south jetty. The jetties have not been repaired 

 since 1934 and are considered to be in good condition. 



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