Date(s) 
1964- 
1966 
1967 
Table 9 (Continued) 
Construction and Rehabilitation History 
The jetties underwent major rehabilitation using the recommendations 
and design proposed in 1962 (Figure 11). The new seaward ends of the 
4,950- and 3,550-ft-long repair sections terminated 790 and 1,135 ft 
from the original seaward ends of the north and south jetties, 
respectively. The south jetty repairs consisted of a rebuilt gulf 
side slope, a 200-ft-long head section, and a 250-ft channel side 
spur located 550 ft landward of the head. The north jetty repair 
section had the landward 2,410-ft channel side and adjacent (seaward) 
2,250-ft gulf side slopes rebuilt. The final 300 ft were rebuilt as 
a transition and 200-ft head section. The head sections had a crown 
elevation of +6 ft mlt, a 32-ft crown width and 1V:3.5H side slopes. 
The 16- to 18-ton cover stone was placed as a double layer on the 
side slopes and single layer on the crown. The 200- to 4,000-lb core 
stone was partially supplemented with 0.5- to 4-in. filler stone (in 
a section extending beneath the crown at 1V:1H side slopes) for the 
purpose of decreasing structure permeability. The 0.5-in. to 200-1b 
blanket stone was placed in a 5-ft-thick layer and extended 50 ft 
beyond the toe of the cover layer. The jetty trunk sections were 
rebuilt to +6 ft mlt and a 1V:2.5H side slope. The crown extended 
two cover stones in width from the existing 12-ft-wide concrete cap 
sections or 14 ft from the center line of the north jetty grouted cap 
(1,800-ft section). The single layer of cover stone varied from a 
minimum of 2 to 4 tons at the south jetty landward end to a maximum 
of 16 to 18 tons at the jetty seaward ends. The blanket layer was 
placed in 3-, 4-, or 5-ft thicknesses and extended 10 ft beyond the 
toe of the cover layer. Prior to placing the core stone the existing 
void spaces were chinked with filler stone. The filler, blanket, and 
core stone size ranges were the same throughout the repair sections 
(see above). The south jetty groin consisted of core stone placed to 
-18 ft mlt, a 10-ft crown width, and 1V:1.5H side slopes. The core 
stone was placed on a 5-ft layer of blanket stone which extended 
10 ft beyond the toe of the core stone. The total cost of rehabili- 
tation was $3,367,000 and required 410,250 tons of stone. The jetty 
design was based on Hudson's slope stability formula, depth- and 
fetch-limited wave heights, and a maximum storm surge level of +13 ft 
mlt. The 18-ton maximum cover stone was inadequate for maximum 
design conditions but was selected for practical and economic 
reasons. 
Hurricane Beulah's passage in October displaced cover stone at 
several locations, with an estimated 100 pieces missing or displaced 
from each jetty. Near the landward ends of the jetties sand was 
washing or piping under the concrete caps and into the ship channel. 
It is not known whether this piping was due to the storm or if it had 
been a previous problem. These sections were located from sta 12+00 
to sta 24400 on the north jetty and from sta 10+00 to sta 25+00 on 
the south jetty (landward ends at sta 0+00). 
(Continued) 
44 
