Office of Coastal Management

LA Officials Take Step to Require the Corps of Engineers to Beneficially Use Lower Mississippi River Dredged Material

The State of Louisiana took a bold step today to require the U.S. Army Corps of Engineers to use sediment dredged from the Mississippi River to restore eroded wetlands in Louisiana – rather than wasting the material. 

A letter sent by the State to U.S Secretary of Commerce Gary Locke will trigger a provision in federal law providing for Locke to assist in the development of a solution to ensure unimpeded maritime commerce on the Mississippi River while ending the Corps’ practice of discarding dredged sediment that could be used to restore Louisiana’s disappearing coast. 

Last week, a federal judge determined that similar management practices on the Mississippi River Gulf Outlet exacerbated hurricane damages in the Greater New Orleans area. 

At issue is the Corps of Engineers’ Fiscal Year 2010 plan for maintenance dredging in the area of the Mississippi River’s Southwest Pass. Specifically, the State of Louisiana wants the Corps of Engineers’ plan to provide for the beneficial use of dredged material from the dredging activities.  

Under the Coastal Zone Management Act of 1972, states may determine that federal agency actions are inconsistent with state coastal resource plans.  The State of Louisiana determined that the Corps of Engineers’ practice of dumping dredged sediment into the deep waters of the Gulf of Mexico or other areas that fail to reestablish coastal lands is inconsistent with the Louisiana Coastal Resources Program. 

The Corps of Engineers has historically dumped the dredged material from that annual dredging offshore or in open water at the head of Pass a Loutre. Dumping the material at the head of Pass a Loutre has resulted in blocking fresh water and sediment flow to the eastern Mississippi Delta, accelerating the loss of coastal wetland, while dumping the material offshore effectively wastes needed sediment.

Research conducted by the Louisiana Departments of Natural Resources and Governor’s Office of Coastal Activities shows that materials removed during maintenance dredging in other states is being used to build land and enhance coastal wetlands.

Dredging of the Southwest Pass area to maintain proper channel depths for navigation and commerce involves the removal of 5 million to 20 million cubic yards of sediment each year. While the State of Louisiana strongly supports the maintaining of shipping channels, it has asked that beneficial use of the dredged material also be made a key component of the management of the river.

“We are losing more than 25 square miles of coastal wetland each year. We cannot spare or waste any resources in the fight to preserve our coast,” DNR Secretary Scott Angelle said. “It is critical that we find a way to put this material to work in projects that help us preserve and restore coastal land.”

CPRA Chairman Garret Graves said using dredged materials beneficially to rebuild wetlands is the fastest way to begin slowing and possibly halting coastal erosion in Louisiana.

“The Corps removes about 60 million cubic yards of sediment from navigation channels in the State of Louisiana every year but only about 12 percent of that material is used to rebuild our vanishing wetlands,” Graves said. “Reasonably, 45 million cubic yards could be used every year. As much as 10 square miles a year could be built with the material that is being wasted.”

Graves equated the wasting of the dredged materials along the lower Mississippi to similar activities that removed sediment from the Mississippi River Gulf Outlet (MRGO) in St. Bernard Parish over the last 50 years. The environmental devastation and loss of wetlands from the construction and maintenance of the MRGO has caused the destruction of nearly 20,000 acres of wetlands east of New Orleans.

“Just last week, a federal judge determined that the Corps’ operation and maintenance of the MRGO contributed to Katrina damages in parts of New Orleans and St. Bernard Parish. Prior to the Corps’ construction of levees on the Mississippi River, Louisiana was actually growing in size each year.  Since the levees were built, we have lost 2300 square miles of land.  The era of wasting dredged sediment is over.  We must reestablish the use of this material to help restore our coast as Mother Nature did for millions of years” he said. “Providing adequate depths on the Mississippi River is critical to ships carrying trade from the United States and around the world.  This must remain a top priority.  I am confident that Secretary Locke and the NOAA Administrator, Dr. Jane Lubchenco, can help the Corps to strike the right balance among navigation, restoration and hurricane protection.”

 Graves also referenced a recent study released by LSU geology professors Mike Blum and Harry Roberts that shows the Mississippi River, because of levees and dams built throughout the river’s basin, carries half its historic sediment load.
“We simply can’t afford to waste any of the sediment carried by the river if we hope to have a fighting chance to restore this coast,” he said.  “There is no doubt that we can build the kind projects needed to restore and protect this coast but only if we dedicate the necessary resources. Sediment and water from the Mississippi River is, perhaps, the most important of those resources.” 

Graves said he applauds the efforts and the urgency demonstrated by the Corps in building hurricane protection in the New Orleans area since 2005. But, he said that same sense of urgency and commitment is needed to restore Louisiana’s imperiled coastal wetlands. 

Louis Buatt, DNR assistant secretary with the Office of Coastal Management, said that the request for assistance from the Department of Commerce  does not represent the first attempt by DNR and the state of Louisiana to make beneficial use a part of the Corps of Engineers’ annual maintenance dredging.

DNR has substantially increased efforts to bring the Corps’ maintenance dredging program into compliance and consistent with the state’s federally-approved coastal management program, but has not been successful, Buatt said.

While beneficial use of dredged material would increase the cost of the maintenance dredging, cost alone is not reason enough for the Corps of Engineers to leave beneficial use out of its project plan, he said.

“The Corps’ role should be to request the funding needed to make sure projects meet the standards and are consistent with our coastal management program,” Buatt said. “It is the role of the U.S. Congress to decide whether to provide the necessary funding.  By not requesting the funding the Corps is effectively making the decision that is reserved for Congress.”

State's letter to US Department of Commerce (13kb)
State’s letter objects to consistency (1.8mb)