DREDGING AND DOG
RIVER
Ford, David Wesley Department of Earth Sciences, University of South Alabama, Mobile AL, 36668 Email: dwford24@hotmail.com.
An initial study by the Army Corps
of Engineers showed no reason to dredge Dog
River. After the idea was repackaged as an
environmental restoration project, money was allocated from Congress for the
project. My goal is to enlighten the
public about this project, and let them decide if there are reasons to justify
the huge price tag associated with dredging the river.
Keyword: Dog
River Dredging
Introduction
Dredging is defined as “excavating or moving soil or rock by
dredger” (Bray, 1979). The basic reasons
for dredging are the following:
- To
create a greater depth in a river, lake, or sea
- To
fill a void with material excavated from underwater
- To
gain material for construction
- To
gain minerals
- To
improve the environment
A notable example of dredging would be the case of the Great
Lakes. Approximately four
million cubic yards (400,000 truckloads) of soil are removed from its channels
each year. The reason for this continued
dredging is simple; economic gains result because of the tremendous amount of
commercial shipping taking place (Army Corps of Engineers, 2002).
The dredging of Hudson River in New
York stands as a case of environmental
improvement. Recently, GE has been
ordered to pay nearly 2 million dollars for the removal of PCB’s, a known
carcinogen, from the river bottom (Asscoiated Press,
2001). Again, the advantages of such a
project are clear. No one wants
substances detrimental to health sitting in their river.
The case for dredging Dog River,
AL is a controversial one. It is not without its critics and supporters,
and it is not the stereotypical situation of environmentalists vs. big money as
often advertised in political cartoons.
There are environmentalists who support the project, and there are those
who do not. The same can be said of the
employees of the Army Corps of Engineers; some think it is a great idea, while
some see it as a waste of money.
It is no secret that the Dog River Watershed has been
neglected and mistreated for decades, thereby contributing to numerous
problems, including the buildup of sediments on the river bottom. Since 1950 development has claimed much of
the former wetlands that once played a role in water quality of the
watershed. Precipitation was filtered by
these wetlands, and they also trapped sediment.
Poor Best Management Practices by construction companies has only
exasperated the problem of sedimentation, leading to the shallow waters found
in many parts of Dog River
proper and its tributaries. The Army Corps of Engineers recently began
dredging the river to remove these sediments and restore the river to historic
depths (Parris, 2001).
The Dog River
dredging project was authorized by Section 518 of the Water Resources
Development Act of 1999. This Act called
for $1,500,000 of Federal Money to be used for the project. On July 24, 2001 the Supplemental
Appropriations Act was signed which stated ‘That using $1,900,000 of the funds
appropriated herein, the Secretary of the Army, acting through the Chief of
Engineers, is directed to undertake the project authorized by Section 518 of
Public Law 106-53, at full Federal expense.’ The project has been undertaken with
congressional approval and without a feasibility study, and also without an
authorization for annual Operation and Maintenance. It is a one-time project that is completely
federally funded (Parris, 2001).
The scope of the dredging is as follows: A portion of Dog
River proper has been dredged with
a channel of dimensions 40’ by 7’. The
channel extends for a length of 19,000’.
The mouths of Moore Creek, Halls Mill Creek, and Rabbit Creek are being
dredged to dimensions of 40’ by 8’. The
length of these channels extends from 1200, 1500, and 2100 feet,
respectively. In all, it is estimated
that 116,679 cubic yards of material will be collected in barges and relocated
to Galliard Island,
a man-made island located in Mobile Bay
(Flakes, 2001).
Research Question
The purpose of my inquiry and investigation into this
project is to shed light on the subject, and to try and determine whether the
dredging of Dog River
may have favorable consequences worthy of its two million dollar budget. How long will any
expected benefits wrought by this project last?
Do the pros outweigh the cons?
What are the pros and cons of this project?
Methods
I have gathered information concerning the Dog River Pilot
Project from several sources. First, I
have interviewed persons directly involved with the project itself, from the
Engineer in charge of contracts, to the Dredgemaster
overseeing the actual work. I obtained a
copy of the Engineering and Documentation
Report and Environmental Assessment
prepared by the Army Corps of Engineers, Mobile District, as well as several
other articles containing information about the controversy surrounding this
topic. I also collected sediment samples
from areas both dredged and those that have not been dredged, in order to
ascertain if expected changes had occurred according to the Draft Engineering Documentation Report.
Results
It turns out that there are many interesting aspects to this
project. First of all, how is it that
the project was given life at all? The
Army Corps of Engineers does work that is concerned mostly with flood control
and navigation projects. A prerequisite
of any project is that it has economic returns (Reilly, 2001). The Dog River Pilot project has no economic
returns. How did it get started? The story is as follows:
Representative Sonny Callahan has a house on the river. For years he listened to complaints from
neighbors about the depth of the river (Kamen,
2001). People were having trouble
getting their big recreational boats into the water. An initial study in 1997 by the Army Corps of
Engineers, however, found no reason to undertake a dredging project. After all, there is no real commercial
traffic on Dog River. After more complaints, however, many people
feel like Callahan gave in to the pressure.
A loophole was found in the Corps’ statutes. This loophole is the environment. If the plan to dredge the river could be
re-packaged as an environmental restoration project, then economic returns
could be thrown out the window (Reilly, 2001).
The package was completed, and because of Callahan’s
position of power, he was able to clear the next hurdle: the hurdle being that a local sponsor was
required to put up 35 percent of the cost required of all environmental
restoration initiatives. He merely
erased this clause, and added the extra money with the Supplemental
Appropriations Act, bringing the total to $1,900,000 (Mobile Register, 2001).
So what are the environmental benefits anticipated from the
dredging of Dog River? According to the Army Corps of Engineers
Report, it is the following:
- improved water quality, involving water clarity
and dissolved oxygen
- increased tidal flow
- restoration of the river bottom to coarser
sediments
- removal of shoaled areas along the river and its
tributaries (Bray, 1979).
The report lists as “incidental” the benefit of more
recreational uses by boaters of the finished project. In my time period, I have only been able to
begin the process of determining whether this project will really improve
environmental conditions. Time will tell
the fuller story. I collected sediment
samples from both inside and outside of the dredged channels. I found no significant difference between the
two. To say that this small portion of Dog
River has been restored to coarser
sediments would be a false statement.
Sediment samples consisted of the same clay sludge whether they were
obtained from inside or out of the channels.
A worker explained to me that they dredge below the required depth,
because gravity pulls sediment back down the dredged slope. This means that the material left after the
dredging is completed is the same material that was being removed.
As far as increasing tidal flow and improving water quality,
one needs only look at the scope of the project to have reservations. The overall portion of Dog
River that is being dredged is very
small compared to the size of the river.
Further, the dredging does not extend all of the way to Mobile
Bay, and is therefore very unlikely
to help with any flushing action. It
appears that the best effect of the dredging project will be to have narrow
channels for big boats, and shoaled areas removed.
Upon interviewing workers on-site at the river, I was
surprised to learn that the effects of this project will last only “a few
years”. I was told by a man who has been
in the dredging industry for over 30 years that Dog
River would need to be dredged
again in only a few short years because of how much sediment is being drained
as a result of construction around Mobile. He pointed out that this was his favorite
part of being in his business, as he does not have to worry about job security
(Personal Interview, 2002).
Discussion and Conclusions
The dredging of Dog
River has gone forward before a
plan to get to the root of the problem has been fully addressed. The project benefits a few owners of very
nice, big boats, while it takes money out of the pockets of everyone. While it is clear that the dredging is not
harming the environment in any way (such a project has to meet many
qualifications from ADEM, etc.) it is also very clear that a great deal of
political maneuvering was involved to get the project underway. The case for environmental
benefits require a bit of imagination.
Reading the justifications for this project is analogous to reading a
study conducted by a cigarette company showing that smoking is not as bad as
once thought. It will be nice for the
owners of big boats for a few years, but what then?
It will be interesting to note any changes with Dog
River in the next few years. The depth of the channels can be monitored to
determine how long they will actually remain at their current dredged levels. In addition, monitors can keep an eye out for
the possible reestablishment of submerged seagrass
beds that the environmental initiative hopes for.
References Cited
Army Corps of Engineers. Great Lakes and Ohio River Division. Available:
Online www.lrd.usace.army.mil/gl/dredge.htm
Bray, R. N., 1979: Dredging, A Handbook for Engineers.
Editorial. Mobile Register. 10-19-01
Editorial. Associated Press. One of America’s Largest Dredging Projects. 12-06-01. Available: Online.
www.canoe.ca/AllAboutCanoesNews/dec6_hudson-ap.html
Flakes, Curtis M. Revised Joint Public Notice, Dog
River Pilot Project
Kamen, Al. June
29, 2001; Page A35 GOP Defection:
Nimby to Yimby Washington
Post
Lago, Ken. Personal Interview. 3-27-02
Parris, Jennifer and Rees, Susan. April 2001.
Draft Engineering Documentation
Report and Environmental Assessment
Rush, George.
Personal Interview. 3-21-02