Table 12 (Continued) 
Date(s) Construction and Rehabilitation History 
1957- The jetties were repaired at their seaward ends. New riprap, core, 
1959 and 14- to 18-ton cover stone were used. Existing cover stone was 
reset, and concrete was placed (similar to previous capping). A 
total of 20,500 tons of stone and 600 cu yd of concrete were placed 
at a total cost of $268,000. 
1961 Approximately 1,270 lin ft of stone embankment was placed along the 
section of channel shoreline adjacent to the landward end of the 
north jetty. The purpose of the embankment was to reduce shoreline 
erosion which threatened to flank the jetty. A 3-ft-thick layer of 
0.5-in. to 200-lb stone was placed at about the mlt contour. The 
width of the layer was roughly 25 ft. Total cost of this shore pro- 
tection was $40,500. In September several sections of the jetties 
were damaged during Hurricane Carla. The south jetty received the 
most damage. About 45 ft of its seaward end was severely damaged, 
and large holes developed under several sections of the concrete 
cap. The holes were caused by displacement and settlement of cover 
and core stone. Near its seaward end, about 200 ft of cap had 
collapsed and an additional 70 ft was severely damaged. On the north 
jetty major areas of damage occurred at its seaward end, with 190 ft 
destroyed and a 380-ft channel side section damaged by undermining 
near the landward end. The magnitude of stone displacement and 
undermining of the cap was much smaller on the north jetty. Damage 
to the seaward ends of the jetties was believed to be due partly to 
scour along the jetty toes and partly to the existing 1V:2H side 
slopes which were too steep for the existing cover stone and storm 
waves. 
1965- A 1,825-ft section of the south jetty was rehabilitated, and repairs 
1966 were made to 580 ft of the north jetty. Starting from its seaward end 
the south jetty repairs extended a distance of 625 ft along both side 
slopes and continued for an additional 1,200 ft on its gulf side. The 
design geometry (Figure 15) consisted of a +6 ft mlt crown elevation, 
a 20- to 30-ft crown width (seaward end widest), 1V:4H side slopes on 
the 200-ft-long head section, and side slopes of 1V:2.5H and 1V:4H on 
remaining gulf and channel sections, respectively. A 3- to 5-ft-thick 
bedding layer of 0.5-in. to 200-lb stone was placed, extending from 10 
to 50 past the toe of the new cover stone. (The thicker/wider layer 
was used on the 1V:4H sections.) The core stone varied from a minimum 
of 200 lb to maximums of 1,000 and 4,000 1b between landward and sea- 
ward ends, respectively. To reduce sand transport through the jetty, 
part of the gulf side core stone adjacent to the old cover stone was 
combined with 0.5- to 4-in. filler stone. The cover stone varied from 
2 to 4 tons on the landward gulf side, increasing in size in the sea- 
ward direction to a maximum of 16 to 18 tons. The entire channel side 
was 16 to 18 tons). A double layer of cover stone was used on the 
side slopes of the head section. Additional repairs were made by 
(Continued) 
49 
