Table 7 



Grand Isle Jetty 



Jefferson Parish, Louisiana 



Date(s) Construction and Rehabilitation History 



1958 The jetty was constructed by the Louisiana Department of Public Works 



1959 approximately 1,000 ft west of the eastern end of Grand Isle. The 

 Jetty was approximately 935 ft long. It was founded on a timber 

 mattress and had a 6-ft crown width with IV on 1.5H side slopes. 



1964 The jetty was extended 1,400 ft by the State of Louisiana with 



essentially the same cross section used for initial construction. 



1966 The jetty at the east end of Grand Isle (west side of Barataria Pass) 

 was repaired with shell and stone (Figure 18). Existing center-line 

 elevations (October 1965 survey) varied from -8.5 to +3 ft mean sea 

 level (msl). The repairs were carried out along 2,320 ft of the 

 jetty from 2+60 to 25+80 (seaward end). The landward end of the 

 repair section was approximately 200 ft from the existing shoreline. 

 The design section (Figure 18) called for a +3 ft msl crown elevation 

 (+4 ft msl on landward 340 ft), a 6-ft crown width, and 1V:1.5H side 

 slopes. A bedding layer of shell was placed at two sections, 12+90 

 to 14+20 and 15+80 to 16+60. A total of 7,500 tons of 500-lb to 4- 

 ton stone and 770 cu yd of shell was placed at a total cost of 

 $83,500. After the jetty repairs, the State of Louisiana placed 

 about 200 lin ft of sand dike between the existing shoreline and the 

 landward end of the jetty. The dike was to have a crest elevation of 

 +8 ft, and additional shell and 25- to 1,000-lb stone were to be used 

 at the jetty junction. The cost for the dike was to be reimbursed by 

 the Federal government (no details). 



1972 A jetty was constructed at the west end of Grand Isle. 



1985 Additional information on the jetty was not found, and its present 

 condition is unknown. 



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