2
Construction and Rehabilitation History
1964-
The west jetty was extended 300
seaward as part of improvements
which included deepening the 100-ft-wide channel from -4 to -8 ft
1965
mlw. The purpose of this extension was to reduce potential channel
from the east jetty,
shoaling. Constructed parallel to and 250
the extension brought the outer ends of the jetties abreast of one
another. The rubble-mound cross section was placed to +15 ft mlw,
6-ft crown width, and side slopes of
The section was made
bedding layer of 1-to 50-lb stone, a core of 10-
up of a
to 2,000-lb stone, and a 3-ft-thick cover layer of 1- to
stone.
The outward facing semicircle at the jetty head had an 8-ft crown
cover layer of 3- to
side slopes, and a
width,
stone. A total of 950 cu yd of bedding stone and 9,000 tons of core
and cover stone were placed for a cost of ,000. Cover stone size
was selected using Hudson's slope stability formula and depth-limited
wave heights of 7.5 and 10.5
for the trunk and head, respectively.
Repairs were made by placing quarried stone on the east jetty seaward
1969
Also included were repairs of
slope from approximately
to
an undermined channel side section between
and
and a
breeched section, with a maximum depression of about 9 ft, between
Prior inspections between 1964 and 1967 indicated the
and
jetty was in poor condition. The seaward slope armor stone was
ft mlw, a minimum, composite top width of 6 ft (in-
placed to
cluding the existing capstone), and a
side slope. The core
consisted of chips to 2,000-lb stone, and the cover layer was 5- to
8-ton stone. The damaged sections were repaired by resetting
existing stone blocks and adding new stone. The design channel side
A total of 5,600 tons of stone was placed for a
slope was
cost of 0,800. The west jetty was in good condition with only
minor displacement of armor stone along the recent extension.
Visual inspections indicated the jetties were in poor condition.
the east jetty the seaward side of the head (stone pier) was severely
1978
damaged, void spaces in the seaward slope armor stone were evident,
and the channel side toe was in a deteriorated state due to under-
mining. On the west jetty extension the outer 150 ft had large
to
amounts of displaced cover stone with typical elevations from
ft mlw. The remainder of the extension was in considerably
better shape with only minor displacement and settlement of the armor
stone.
The jetties were repaired with armor stone along the damaged sections
18
91
observed on previous inspections and a topographic survey. The
channel side of the east jetty, from
to
was repaired with
mlw, a
side
5- to 8-ton stone placed to an elevation of
slope, and a top width varying from 0 to ft. The east jetty's
using 5- to 8-ton stone
seaside was repaired between
and
(Continued)
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