Table 12 (Concluded) 



Date(s) 



1977- 

 1979 

 (cont. ) 



Construction and Rehabilitation History 



1980 



1984 



the base of the existing Jetty and extended 10 ft beyond the end of 

 the new cover layer. The seaward end repair was identical to the 

 1971-1972 work, except that 1V:3H side slopes were used throughout. 

 Displaced cover stone was reset on the adjacent 100 ft of jetty. The 

 north jetty shore protection was extended 1,470 ft along the channel 

 shoreline; this included 150 ft of the existing shore protection 

 which was salvaged and rebuilt, and repairs were made to the existing 

 section. The design was nearly identical to that used in 1968 on the 

 existing shore protection. (Toe protection was 200 to 1,000 lb and 

 placed with a top width of 5 ft.) The jetty design was based on 

 Hudson's equation with a maximum wave height of 26.5 ft (trunk) and a 

 maximum surge level of +10 ft mlt. Similar to previous improvements, 

 the selected jetty design was chosen for economic and practical 

 considerations in lieu of a "no damage" design. Total cost of the 

 jetty repairs and shore protection was $5,905,000 using approximately 

 140,000 tons of stone. 



In August, storm waves from Hurricane Allen caused significant damage 

 to the jetty heads and a section of the north jetty trunk had been 

 breached. The breached section was about 50 ft long and located 

 350 ft from the head. 



There are several places along the jetties where the foundation has 

 settled, resulting in the cover stone lying below mlt. 



TYPICAL CONCRETE CAP REPAIRS 

 (SOUTH JETTY-1965, NORTH JETTY-1979: 



1979 NORTH JETTY TRUNK SECTION 



Figure 15. Typical repair sections of the Brazos Island jetties 



52 



