Table 4 (Continued) 



Date(s) Construction and Rehabilitation History 



1950- 122+20, and 126+30 to 142+15 (all these sections consisting of the 

 1952 narrower, 3-ft-wide blocks). The total cost for the concrete and 

 (cont.) stone capping was $889,000. 



1954 The east jetty was repaired over a distance of 3,125 ft using 



approximately 18,900 tons of stone. Total cost of the repairs was 

 $286,000. From surveys of the east jetty taken in April 1953 and 

 July 1956, it appears that most of this work was carried out at the 

 landward end between 127+00 and 163+00. 



1956- The east jetty was repaired with stone along its entire length from 

 1957 127+00 to .250+00 (seaward end) and extended 800 ft at its landward 



end (to about 119+00). The seaward end of the west jetty was capped 

 with concrete between 174+98 and 191+50 (Figure 14a, seaward section 

 where rectangular cap stone was placed in 1951). The east jetty 

 design cross section had an 8-ft crown width at +6 ft mlg and 1V:1.5H 

 side slopes. Landward of 146+00 the design crown width was 5 ft. 

 Two methods of stone placement were used: either additional cover 

 stone ( 1 to 5 tons) was placed, or the existing cover stone (4 to 

 10 tons) was temporarily removed and additional 500- to 8,000-lb core 

 stone was placed. The landward extension was to employ 200- to 

 4,000-lb stone, with the larger pieces placed as cover stone. 

 Center-line surveys of the east jetty taken in April 1953 and July 

 1956 showed a general settlement of 1 to 2 ft and typical crest 

 elevations of +4 to +5 ft mlg. The west jetty concrete cap was to be 

 cast in place with individual blocks weighing not less than 15 tons. 

 The blocks were to be keyed, be 8 ft in width, and have a +6 ft mlg 

 crown elevation. Surveys of the west jetty taken in February 1953 

 and August 1956 showed a general settlement of 1 to 2 ft and typical 

 crown elevations of +4 to +5 ft mlg, for the seaward repair section. 

 Cost of the repairs and some work on the South Pass jetties (less 

 than 20 percent of total) was $499,500. 



1960 Repairs were made to the 3-ft-wide concrete cap section of the west 

 jetty by resetting the blocks that had been dislodged during storm 

 waves of 18 November 1957 and 16 February 1959. About 1,315 lin ft 

 of cap was reset and buttressed with additional stone at sections 

 48+40 to 50+50 and 131+50 to 143+00. The design cross section 

 (Figure 14b) used to supplement the concrete blocks consisted of a 2- 

 ft-thick bedding layer of 25- to 200-lb stone, followed by 200- to 

 2,000-lb stone placed to +2 ft mlg (1V:1.5H side slopes and a 5-ft 

 width on either side of the cap), and 4- to 6-ton stone was placed on 

 either side of the cap. The principal purpose of buttessing was to 

 provide a more stable cross section for the concrete blocks. The cap 

 sections were buttressed with 16,400 tons of stone at a cost of 

 $173,600. 



(Continued) 



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