Smith
Point: Construction of Beneficial Use Sites
Construction is ongoing in Trinity Bay on
three Beneficial Use Sites (BUS) that will eventually contain dredge
material from the upcoming maintenance dredging of the Channel to Smith
Point. Smith Point is located along the eastern shore of Trinity Bay south
of Anahuac, Texas. The channel is a portion of the Channel to Liberty, the
only portion currently sustaining commercial traffic. There are oyster
production facilities at Smith Point that employ between 200 to 300
people. In FY02 Galveston District received a Congressional Add to restore
project depth in the channel to allow the oystermen access to the
facility.
After receiving the request, a Public Workshop
was held to determine local needs. A channel survey disclosed that
approximately 750,000 cy of material would need to be removed to restore
the authorized channel dimensions, 9 feet deep by 150 feet wide. There
were no available placement areas, so coordination began between the COE,
the Chambers-Liberty Counties Navigation District (local sponsor), local
oystermen, the USFWS, TPWD, Audubon Society, and Galveston Bay Foundation.
After much discussion and coordination, a plan was developed to use the
material 100% beneficially. The plan called for development of Beneficial
Use Sites (BUS) 1-3, into which the dredge material would be placed.
BUS1 is Smith Point Island - an area frequented
by several species of birds. Dredge material will be used here to increase
the size of this island. The first order of business was to construct a
stone breakwater to the north of the island to stop the island from
eroding and to contain the dredge material behind it. The breakwater is
approximately 2,300 feet long, with a 5-feet wide cap, and built to an
approximate elevation of +1.5 to +2 MLT. The breakwater will also prevent
dredge material from smothering nearby oyster reefs. Good coarse-grained
material and shell hash will be pumped from the adjacent channel and used
to good benefit in this location.
There is a lot of oyster and shell in the channel
toward the eastern tip of Smith Point Island. This shell will be pumped to
an area in the open bay, and to the north of the island. The shell will be
placed so as to encourage oysters to attach and create a new oyster
reef.
BUS2 is a 138-acre marsh creation site located
just north of Robbins Memorial Park and the Channel to Smith Point.
Approximately 8,500 linear feet of geotubes will be placed to form the
U-shaped perimeter of the marsh. The geotubes will be placed to varying
elevations (+3-3.5 feet) with periodic "circulation" tubes that
will be collapsed to a lower elevation in the future to allow water to
circulate through the marsh. Bertucci Corporation is the subcontractor
currently placing the geotubes. They are filling the tubes with varying
material from the adjacent bay bottom and from "borrow ditches"
within the marsh. Approximately 650,000 cy of fine-grained dredge material
from the adjacent channel will be placed inside the area defined by the
geotubes to varying elevations within the marsh.
Once dredging is complete, marsh grasses such as
spartina alterniflora will be planted to ensure vegetative cover by the
end of the second growing season. The circulation tubes will then be
collapsed allowing tidal penetration into the dredged material will be
used beneficially. Construction of a beneficial uses site of approximately
357 acres, will replace the portion of the Shoal Point dredged material
placement area that would be utilized for the development.
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