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Possible Long Term Solutions
The following is a list of possible long term solutions for Dauphin
Island, based on research into our situation, as well as what other coastal communities are doing.
The hope is that one or more of these solutions could be funded and put
in place within a year or two.
Dump or pump dredged sand closer to the island
Since the Mobile Outer Bar Channel dredging is
interfering with the natural littoral drift from Fort Morgan (and points
east) to Fort Gaines (and points west), the dredged sand should be sent
- via barge or pipeline - to the area where it would naturally flow
otherwise: Dauphin Island's south shoreline. The sand is currently
dumped too far out and is "wasted" in deep waters. If the dredged
sand deposition location could be changed to points closer to the
island, this alone may be sufficient to keep the south shoreline
nourished on an ongoing basis. (See
Sand
Deposition Location)
We hope to influence the Governor, Alabama State
Legislature, Alabama’s Congressional representatives, and the Alabama
State Port Authority to instruct the Corps of Engineers to deposit the
sand dredged from the Mobile Harbor ship channel closer to Dauphin
Island in a manner consistent with the Corps’ 1978 recommendation that
was never fully implemented.
For more information, see
Dredging.
Widen the Beach
Many sources agree that whatever solution is used to
help provide and retain sand, it is necessary to also widen the beach. Since
the south shoreline has lost 100 feet or more in width of sand over the
last few years, this should be restored in conjunction with any
retaining structure or any other solution. Sand could be trucked
in, or pumped via pipelines, from locations with a more abundant supply.
Jetties
A number of people have suggested jetties to help trap
sand and help it to accumlate on the shoreline. Dr. Scott Douglass
has said that a jetty or groin installed just east of the Katrina Cut
would help. Perhaps a jetty could also be installed just west of
the Katrina Cut, to help fill in the cut as well. The cut has
created an oversalinated environment in the Sound and restoring it would
go a long way to reviving the fishing industry there, as well as
protecting the coastal marshes near the mainland.
Pipelines under Bienville
Bury pipelines under Bienville Blvd and employ hydraulic dredges
to pump some of the sand from the massive washover sand fans
(created during Hurricane Katrina) from the north shore to
the south shore. This solution, once implemented, could be
used periodically to help replenish the south shore.
Seawall
One possibility is to build a hard seawall of concrete or other material,
such as that used in places like Galveston. With an
elevation of app. 20 feet above sea level, a tall seawall is do-able
for Galveston, but this may not be workable for the low elevation of Dauphin Island.
But it is worth examining. A hard seawall could be constructed
much like a sand berm, except that it would hold up to a great degree
better against hurricane winds and storm surge. One of the
drawbacks of this option is a reduced aesthetic. A vegetated sand
dune or flat beach is the look to which we are accustomed on Dauphin
Island.
Artificial Reef
Numerous coastal communities across the U.S. have
employed artificial reef systems some distance offshore as a method by
which to slow down wave action. This may or may not be a good
solution for Dauphin Island but it is worth considering.
Related Links
Solutions
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