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
long, respectively) were constructed using steel sheet piles
2,200
)
placed to an elevation of
which converge to a distance of 8 0
at their seaward ends, provide
0
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 and 9
wide) were placed at the
thick). Stone blankets
I
base of the cylinders. The total cost of jetty construction was
which included placing
of sheet pile and
sq
950 tons of stone.
Minor maintenance work was done for a total cost of ,000. At the
1950
landward ends riprap was placed in a layer about 2 ft thick, 1 ft
6
wide, and 1 0 ft long. The outer 300
of the north jetty was
0
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-
along the outer 800- and 1,200-ft sections of the
tion (Figure
1965
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
mlt; side slopes were
and the
crown width was approximately 1
0
(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
cover stone. Filler stone (0.5 to in.) also was placed with the
core stone (a section
wide on either side of the sheetpiling and
extending downward at
side slopes). The bedding layer extended
from 5 ft (landward) to
ft (seaward) beyond the toe of the cover
of south jetty bay side rubble
stone layer. The landward 700
mound consisted of a 2-ft-thick bedding layer placed between 0 and
ft mlt followed by a 2-stone-wide cover layer
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
side slopes. At the
and
ft mlt with a 4-ft crown width and
(Continued)
31
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