Up until the late 1960s, the Louisiana scientific community
was in agreement that the marshes of our state were stable, and
that significant erosion was not possible.
This condition of coastal equilibrium was taught in college
classrooms and printed in textbooks.
But in 1968, a young genius named Sherwood “Woody” Gagliano
dicovered that the state of Louisiana was losing a whopping 16.5
square miles of marshland a year. The numbers were clear and indisputable.
Ever since, Gagliano, a lifelong Louisiana resident who holds
three degrees, including a doctorate in geomorphology, from LSU,
has been on a quest to develop projects to save the Bayou State’s
The biggest and most-important of his creations is the Third
Delta Conveyance Channel.
Gagliano and his associate, Johannes van Beek, first formally
introduced the idea in a report they wrote in 1994 for the governor’s
coastal-erosion committee, and in 1998, the proposed channel was
made the key element of Coast 2050.
“I love this project,” Gagliano said. “It won’t solve all our
problems, but it’s the cornerstone of the plan to solve a whole
lot of our problems. It has more environmental benefits than all
the other projects combined.”
As proposed, the Third Delta Conveyance Channel would divert
200,000 cubic feet per second of river water through a break in
the river levee just downstream of Donaldsonville.
Thirty miles downstream from there, around Lake Boeuf, the channel
would split in two, with the water continuing down man-made channels
on either side of Bayou Lafourche.
One channel would empty into the Barataria Estuary, the other
into the Terrebonne Estuary.
Because of the current shallow condition of the estuaries, accretion
of sediments would begin almost immediately, and eventually new
deltas, with the vibrant flora and awe-inspiring fauna that go
along with them, would form in the two estuaries hit hardest by
coastal erosion and subsidence.
The channels themselves would be dug very shallow — about 12
feet deep — to allow the rushing water to maintain its forward
speed and hold its sediment. Once the water encountered the broad
estuary, it would slow down and, as a result, drop its sediment
The fast-moving water would also collect sediment from the bottom
of the channels, and transfer it into the estuaries. Over time,
this would make the channels deeper and allow more water to be
“Those channels, with sufficient flow to carry silt — not clay
or simply fresh water — will build land rapidly, particularly
since we’re letting the channels self-scour. We’d see almost immediate
stabilization (of the marshes),” Gagliano said.
It may sound too good to be true, but it’s not. The problem
is that it’s too good to be cheap.
The entire Coast 2050 proposal would cost $14 billion to implement,
and a full $2 billion of that would go toward the Third Delta
The feasibility of the Coast 2050 plan is currently being studied
as part of the Louisiana Coastal Area Comprehensive Study. If
it is deemed feasible, Coast 2050 could, in 2004, become part
of the Water Resources Development Act, which is a biennial bill
through which Congress funds water-related projects.
But even if Congress votes to approve funding for the Third
Delta Conveyance Channel, the marshes won’t benefit from the sediment-rich
water it promises until at least 2014.
“We conceived of building a control structure plus a small pilot
channel with guide levees, and the channel would be dug only deep
enough to create the guide levees. Then the structure could be
opened incrementally so that the channel could scour. Doing it
this way, we could get it fully operational in less than 20 years
— maybe 10 or 15 years, but certainly not less than 10,” Gagliano
One of the drawbacks of the plan is that it will greatly alter
the hydrology of both the Terrebonne and Baratariaestuaries, and
as the Caernarvon diversion has demonstrated, many Louisianians
don’t like the inconveniences of coastal-restoration projects.
But the way Gagliano views it, we don’t have any choice.
“We’re really fighting a tremendous battle,” he said. “The timelines
are very short. I’m deeply concerned with the lack of a sense
of emergency. There’s no sense of urgency. Unfortunately, it may
take one big storm to get the public’s attention.”