Date(s) 
1939 
1950 
1964- 
1965 
Table 7 
Port O'Connor Jetties 
Port O'Connor, Texas 
Construction and Rehabilitation History 
Located on Matagorda Bay, the north and south jetties (2,256 and 
2,200 ft long, respectively) were constructed using steel sheet piles 
placed to an elevation of +4 ft mlt (Figures 6 and 9). The jetties, 
which converge to a distance of 800 ft at their seaward ends, provide 
shoaling protection for the 12- by 250-ft Gulf Intracoastal Waterway 
channel. The outer ends of the jetties were protected by 16-ft-diam 
sheet-pile cylinders filled with sand and capped with concrete (1 ft 
thick). Stone blankets (4 ft thick and 9 ft wide) were placed at the 
base of the cylinders. The total cost of jetty construction was 
$130,700, which included placing 81,500 sq ft of sheet pile and 
950 tons of stone. 
Minor maintenance work was done for a total cost of $3,000. At the 
landward ends riprap was placed in a layer about 2 ft thick, 16 ft 
wide, and 100 ft long. The outer 300 ft of the north jetty was 
bracketed with timber wales bolted near the top of the sheet piles. 
Pile interlocking had become ineffective due to corrosion. 
The jetties were rehabilitated by placing a rubble-mound cross sec- 
tion (Figure 9) along the outer 800- and 1,200-ft sections of the 
north and south jetties, respectively. In addition, scour protection 
was added to the remainder of the south jetty channel side, and shore 
protection was added at the landward ends of the dikes. The rubble- 
mound sections, with the existing jetties at the center line, were 
placed to an elevation of +4 ft mlt; side slopes were 1V:2H, and the 
crown width was approximately 10 ft (two cover stones wide, one on 
either side of the sheetpiling). The section was built up on a 2-ft- 
thick bedding layer (3 ft at seaward end) of 0.5-in. to 200-lb stone, 
a core of 200- to 1,000-lb stone, and a single layer of 2- to 4-ton 
cover stone. Filler stone (0.5 to 4 in.) also was placed with the 
core stone (a section 3 ft wide on either side of the sheetpiling and 
extending downward at 1V:1H side slopes). The bedding layer extended 
from 5 ft (landward) to 15 ft (seaward) beyond the toe of the cover 
stone layer. The landward 700 ft of south jetty bay side rubble 
mound consisted of a 2-ft-thick bedding layer placed between O and 
+2 ft mlt followed by a 2-stone-wide cover layer (+4.5 ft mlt crest 
elevation). South jetty scour protection was placed on 950 ft of the 
channel side (landward of the rubble-mound section) and consisted of 
a 2-ft-thick by 10-ft-wide layer of 0.5-in. to 200-lb stone. The 
north jetty was extended 50 ft landward, and a 30-ft-long perpendicu- 
lar spur was added at the landward end (bay side) of the south jetty. 
This shore protection used 0.5-in. to 200-lb stone placed between 0 
and +4 ft mlt with a 4-ft crown width and 1V:2H side slopes. At the 
(Continued) 
31 
