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Dauphin Island, AL
Archive of Historical Data, Books, Maps
And Other Materials
Do we really care?
We are destroying the beaches
of Dauphin Island...
By SCOTT DOUGLASS,
Univ. South Alabama
Special to the Press-Register
The debates about the future of the beaches of Dauphin Island have now
reached the point where I wonder if we care enough to save what we love
about coastal Alabama. I say that because - in spite of a recent report
to the contrary - the truth is, we are destroying the beaches of Dauphin
Island.
By not artificially bypassing sand dredged from the south end of the Mobile
Ship Channel, we are also increasing potential hurricane storm surge and
wave damage in the Bayou La Batre area, undermining the Dauphin Island
Lighthouse, and causing tremendous changes to the ecosystem of the south
end of the county. These include killing the most productive oyster reefs
in the state and increasing erosion of the extremely productive wetlands
of the Mississippi Sound. In essence, we are needlessly ruining south
Mobile County to save a few bucks.
The solution is clear: The Port of Mobile, or some other local or state
agency, should fund the additional costs required to put dredged sand
back in the beach system.
Dauphin Island should open access to its beaches to all of the citizens
of Mobile County so that this expense is more politically acceptable.
The sand that comprises the beaches of Alabama flows, in some respects,
like a river of sand along the Gulf shore in response to waves. Most of
that movement is to the west until the sand reaches an inlet, or "pass,"
like Mobile Pass - the water between Fort Gaines (on Dauphin Island) and
Fort Morgan. There, the sand should naturally "bypass" to the western
beaches by getting pulled out onto a sand bar or shoal system by the outgoing
tides, and then getting driven back to the beaches by waves to continue
its journey to the west.
At Mobile Pass, however, the sand falls into the south end of the Mobile
Ship Channel, where it is dredged and disposed of in deep water beyond
the beach system. Instead of that wasteful disposal practice, we should
have been artificially bypassing the sand to the downdrift beaches in
order to replicate the natural process that's interrupted by the ship
channel. That is a basic principle of prudent coastal management, and
it is sound coastal engineering practice.
By not following that basic principle, well over 20 million cubic yards
of sand have been permanently removed from the beach system of Mobile
County by the ship channel dredging practices. This is a tremendous amount
of sand. If we had hauled that sand up to the city of Mobile to build
a sand castle, we could have built one the size of the new RSA Battle
House Tower and 100 more just like it. But instead, we dumped the sand
offshore and essentially starved the shoals around the lighthouse and
the beaches of Dauphin Island.
The U.S. Army Corps of Engineers' 1978 report about Dauphin Island and
the dredging problem correctly and prophetically said that if we did not
start artificially bypassing sand, then "erosion would continue to claim
valuable property on the island, ultimately causing hardships for island
property owners and a lessening of the area's attractiveness for recreational
activities.
All of that has occurred and more. A 1992 report by the University of
South Alabama also warned of the problems brewing on the island due to
the offshore disposal of dredged sand. As the primary author of that report,
I never thought things would get this far without being fixed.
Dauphin Island experiences tremendous natural changes because it is a
barrier island next to a very large inlet. Most shoreline fluctuations
nationwide occur in similar locations. The presently ongoing migration
of Pelican/Sand Island onto Dauphin Island at the fishing pier is one
such example. This is geology happening right before our eyes.
The same thing happened around 1710 and again around 1860, so it seems
to be a 150-year cycle. But the recent report by a consultant to the U.S.
Army Corps of Engineers tries to conclude something that is physically
impossible.
Why is it impossible? Because another principle of coastal engineering
is a "sediment budget," not unlike your personal budget, where we keep
track of sand moving into and out of an area. If more sand comes in than
leaves, you have widening beaches. But if less sand comes in than leaves,
your beaches will erode. The dredging is like a continuing series of large
withdrawals from your checking account. And this consultant's report is
arguing that you are broke because you have always spent money, and not
because he has been taking the withdrawals from your account.
Every cubic yard of sand removed by dredging is a cubic yard of erosion
downdrift in the river of sand. It is telling that the report was supposed
to have had a co-author but that co-author could not agree with the impossible
and wrote in a dissent that the report was "inconclusive, at best." This
dissenter is the most highly-regarded coastal engineer in the nation and
has been a member of the National Academy of Engineering for decades because
of his seminal contributions in the field.
One question that I am often asked is, "Why do we not just put the dredged
sand back on the beaches?" The answer, of course, is money. It will cost
more to place the sand back on the beaches, or in shallow water so that
waves move it to the beaches, than to dump it in deepwater. That's because
ocean-going dredges are very efficient at moving large amounts of sand.
But the additional cost of doing the right thing here is very small compared
with the overall cost of dredging cm MDSH and with the cost of the damage
being caused. So, who has benefited from these harmful dredging practices?
We have, in that we have all benefited from the positive economic impact
of the Port of Mobile.
This is not like the so-called "water wars" with Atlanta, wherein another
sovereign state (Georgia) wants to take and use some of the water on its
way to Alabama. We have fought a 20-year legal battle to protect our water
rights. But in this case, we in Mobile County are taking and throwing
away 100 percent of the sand that was on its way to south Mobile County.
We are only hurting ourselves.
We can have a great port and a healthy
barrier island system. Indeed, we must. Question is, do we care? Do we
care enough about the beaches and property of Dauphin Island, the fate
of the Sand Island Lighthouse, the marshes of south Mobile County, the
oysters and the other fisheries, and the future vulnerabilities of Bayou
La Batre and Coden to hurricanes? Or are jobs, jobs and more jobs at any
expense to our environment and our quality of life the only thing we care
about anymore?
Scott L. Douglass is the author of the book "Saving America's
Beaches: The Causes of and Solutions to Beach Erosion" and is a professor
of civil engineering at the University of South Alabama.
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