The MISSISSIPPI RIVER – GULF OUTLET CANAL (abbreviated as MRGO or
MR-GO) is a 76 mi (122 km) channel constructed by the United States
Army Corps of Engineers at the direction of Congress in the mid-20th
century that provided a shorter route between the
Gulf of Mexico
Gulf of Mexico and
New Orleans ' inner harbor
Industrial Canal via the Intracoastal
Waterway . In 2005, although disputed by the Corps of Engineers, the
Hurricane Katrina 's storm surge into the heart of
New Orleans , contributing significantly to the subsequent
multiple engineering failures experienced by the region's hurricane
protection network. In the aftermath the channel was closed. A
permanent storm surge barrier was constructed in the MRGO in 2009, and
the channel has been closed to maritime shipping.
The MRGO begins just east of I-510\'s crossing of the Gulf
Intracoastal Waterway in
New Orleans East and takes a path SSE through
St. Bernard Parish wetlands just west of
Lake Borgne to the Gulf of
Mexico near Gardner Island. Much criticized for its negative
environmental effects, such as saltwater intrusion, wetlands erosion
and storm surge amplification during Hurricane Katrina, the MRGO was
closed in 2009. Maritime traffic was barred on April 22, 2009.
* 1 History
* 2 MRGO\'s operational performance
* 3 Role in
Hurricane Katrina disaster
* 4 Closure
* 5 Surge Barrier
* 6 See also
* 7 Notes
* 8 External links
Conceptually, the MRGO was first envisioned early in the 20th century
as a way to provide shipping with a shorter route to the Gulf of
Mexico. The Port of
New Orleans felt increasingly disadvantaged by the
length of time oceangoing vessels needed to navigate the twists and
turns of the
Mississippi River from the Gulf to the port's wharfs,
versus the much closer proximity to open water offered by its emerging
competitors. The modern
Port of Houston
Port of Houston , in particular, came into
being as a consequence of the completion of the Houston Ship Channel
in 1914. New Orleans' initial response debuted in 1923, with the
inauguration of the
Industrial Canal linking the
Mississippi River and
Lake Pontchartrain , thereby creating the Lower 9th Ward and New
Orleans East .
In 1943, the proposed project was initially presented to the U.S.
Army Corps of Engineers by the Dock Board of
New Orleans under the
name "Alexander Seaway," in reference to Col. Lester F. Alexander, a
member of the Dock Board who was one of the architects behind the New
Orleans plan. A competing plan was also presented by Jefferson Parish,
referred to as the "Arrow to the Americas,' also known as the
Jefferson Seaway .
In a matter of decades, the rapid growth of average ship size in the
20th century rendered the canal locks connecting the Industrial Canal
Mississippi River obsolete; the MRGO as promoted in the 1950s
was to help rectify this deficiency by permitting deep-draft vessels
to access the
Industrial Canal inner harbor. Authorization for the
MRGO was formally provided by the
United States Congress
United States Congress in the Rivers
and Harbors Act of 1956. Construction was completed in 1965.
Due to rapid erosion of the surrounding marsh, the canal was already
as much as three times wider by 1989 than as originally constructed.
When MRGO was built, the channel was 650 feet (200 m) wide at the
surface. In 1989 the average width had become 1,500 ft (457 m). This
degradation continued for the next 16 years.
MRGO\'S OPERATIONAL PERFORMANCE
Intersection of MRGO (to right) with the Gulf Intracoastal
Waterway, as seen from I-510 Bridge Tugboat and barge in MRGO
at Shell Beach, St. Bernard Parish
With the completion of MRGO in 1965, the Port of
New Orleans advanced
a plan to largely abandon its wharfs along the
Mississippi River and
relocate its activities to the inner harbor created by the Industrial
Canal, the Intracoastal Waterway, and the MRGO. This vast project,
termed CENTROPORT U.S.A., never secured sufficient funding and was
quietly jettisoned by the port in the mid-1980s. The France Road
Container Terminal and the Jourdan Road Wharf were the only two
elements realized according to the Centroport plan.
After the abandonment of the Centroport project, the Port of New
Orleans refocused its efforts on improving its infrastructure along
the Mississippi River, and what little maritime traffic the MRGO
hosted progressively dwindled, opening it up to withering critiques.
In 1997, the Competitive Enterprise Institute, a libertarian
organization dedicated to "the principles of free enterprise and
limited government" attacked it on economic grounds: The promised
economic development along the 76-mile (122 km) channel in St. Bernard
Parish has yet to materialize. What the MRGO has delivered is an
$8-plus million yearly maintenance plan for commercial and
recreational waterborne traffic. The nearly $1 billion price tag for
the less than two large container ships a day that use the channel is
baffling, especially considering that the channel only shaved 37 miles
(60 km) off the original route. Worse, the MRGO has created numerous
environmental problems. The rate of bank erosion is estimated at 15
feet (4.6 m) per year.
Hurricane Katrina , environmentalists and others, including
voters in St. Bernard Parish whom the canal was intended to help,
called for its closure.
Criticism intensified following the hurricane, when engineers
implicated the MRGO in the failure of levees and flood-walls
protecting large parts of Greater
New Orleans . MRGO was derisively
termed a "Hurricane Highway" in Katrina's wake, due to its apparent
role in amplifying the impacts of storm surges.
According to a congressional hearing statement made in late 2005 by
Scott Faber of the Environmental Defense Fund, "Traffic on the MR-GO
has fallen by more than 50 percent since 1986. Today, less than one
oceangoing vessel per day, on average, uses this man-made short cut,
which costs approximately $13 million annually to maintain. Like many
waterways constructed by the Corps, the MR-GO failed to attract as
much traffic as the Corps predicted when the project was constructed."
ROLE IN HURRICANE KATRINA DISASTER
Inscription on house in storm-surge devastated neighborhood of
Chalmette, Louisiana suggests that the ruins be used to fill MRGO.
Levees along the MRGO and the
Intracoastal Waterway were breached in
approximately 20 places, directly flooding most of St. Bernard Parish
New Orleans East .
Storm surge from the MRGO is also a leading
suspect in the three breaches of floodwalls along the Industrial Canal
Three months before Katrina, Hassan Mashriqui, a storm surge expert
Louisiana State University
Louisiana State University 's Hurricane Center, called MRGO a
"critical and fundamental flaw" in the Corps' hurricane defenses, a
Trojan Horse " that could amplify storm surges 20 to 40 percent.
Following the storm, an engineering investigation and computer
modeling showed that the outlet intensified the initial surge by 20
percent, raised the height of the wall of water about three feet, and
increased the velocity of the surge from 3 feet per second (0.9 m/s)
to 8 feet per second (2.4 m/s) in the funnel-shaped region between the
converging MRGO and Gulf Intracoastal Waterway. Mashriqui believes
this funnel effect contributed to the scouring that undermined the
levees and floodwalls along the Gulf Outlet, the Intracoastal
Waterway, and the Industrial Canal. "Without MRGO, the flooding would
have been much less," he said. "The levees might have overtopped, but
they wouldn't have been washed away." The Army Corps of Engineers
disputes this causality and maintains Katrina would have overwhelmed
the levees with or without the contributing effect of MRGO since the
storm surge was perpendicular to the length of the canal.
Katrina's passage caused extensive shoaling of the MRGO, resulting in
its impassability for deep-draft oceangoing vessels. Officials of St.
Bernard Parish immediately opposed its reopening. Maritime interests
called for re-opening the Gulf Outlet but equipping it with protective
floodgates, or accelerating construction of the Inner Harbor
Navigational Canal lock project , which when completed would allow
MRGO to be closed without affecting deep-draft commercial traffic.
Closure structure across MRGO at Bayou La Loutre shortly before
completion, July 2009
In May 2007 the Corps of Engineers announced it would close the MRGO
to all traffic and would build an earthen dam across the MRGO in
alignment with the natural ridge paralleling Bayou La Loutre. The
Bayou La Loutre ridge siting was selected to complement future wetland
restoration efforts, as the natural ridge could regain its historic
function of sheltering the marsh and swamp behind from the Gulf of
Construction began in late 2008, and the Corps of Engineers completed
the closure structure across the MRGO at Bayou La Loutre in July 2009.
Main article: IHNC
Lake Borgne Surge Barrier
Closer to New Orleans, a robust 1.8 mile surge barrier costing more
than $1 billion was constructed. The surge barrier closed the narrow
end of the "funnel" described by the convergence of the levees
bounding the northern edge of the
Intracoastal Waterway and the
southern edge of the MRGO, preventing future storm surges from
penetrating into the inner harbor of the
Industrial Canal and
Intracoastal Waterway. Two gates were built, one at Bayou Bienvenue
and another across the Intracoastal Waterway, to permit the passage of
barge and other small commercial traffic during normal weather
conditions. The barrier, the largest of its kind in the United States,
should protect against storm surges up to 28 feet in height. It was
finished in 2011, and is far more significant than the Bayou La Loutre
closure structure. It is two feet lower than the levees it will
connect to in
New Orleans East and St. Bernard Parish. This will allow
water to spill over the control structure before it overtops these
* U.S. Army Corps of Engineers civil works controversies (New
Orleans)#Legal issues in
* ^ History of MRGO
* ^ "Goodbye MRGO: Work begins to close shortcut to Gulf of
Mexico". NOLA.com. 2009-01-31. Retrieved 2009-01-31.
* ^ "MRGO now closed to ships". WWLtv.com. 2009-04-22. Archived
from the original on 2009-04-26.
* ^ "Jefferson Seaway".. 2017-07-06.
* ^ "Inner Harbor Navigation Canal Evaluation Report, March 1997".
Corps of Engineers,
New Orleans District. Archived from the original
on 2006-06-21. Retrieved 2006-04-02.
* ^ Barrett, David (1997), "Washington Waterworld" Competitive
Enterprise Institute, May 1, 1997 (archived 2006-12-08)
* ^ Southeastern Louisiana University, The SLU Poll: Attitudes
Among St. Bernard Parish Voters About The
Mississippi River Gulf
Outlet, Date: 5/26/2004
* ^ Faber, Scott (2005), U.S. Senate Committee on Environment Three
Teams of Engineers Find Weakened Soil, Navigation Canal Contributed to
La. Collapses". The Washington Post. October 24, 2005. Retrieved May
* ^ "Katrina may mean MR-GO has to go",
New Orleans Times-Picayune
, October 24, 2005
* ^ MRGO.gov
* ^ Surge barrier spells death knell for MR-GO, The Times-Picayune,