Innovative Dredge Allows Port Of Morgan City To Thrive

What does refitting an offshore supply vessel (OSV) for space tourism, operating a sprawling scrapyard, loading components onto a barge bound for Venture Global’s forthcoming LNG export facility in Plaquemines Parish and building berthing barges and submarine drydocks for the U.S. Navy all have in common?

All are projects underway along the Morgan City, La., waterfront. What’s more, they’re all possible, in large part, thanks to the Port of Morgan City’s 20-foot navigation channel, which extends from the sea buoy 20 miles offshore through the Atchafalaya River and Bayous Boeuf, Black and Chene.

That hasn’t always been the case.

The Atchafalaya Bar Channel, the final 13-mile offshore stretch of the Port of Morgan City’s navigation channel, collects “fluff,” or fluid mud that, if left unattended, fills in quickly and hampers deep-draft navigation. Mac Wade, executive director of the Morgan City Harbor & Terminal District, said the bar channel, without dredging, would fill in at a rate of up to 3 feet per month. That happened in early 2015, and it killed deep-draft navigation at Morgan City, which went from a growing import-export trade in 2014 to a bar channel depth of just 9.5 feet in the summer of 2015.

The fluff can be moved with a traditional hopper dredge or cutterhead dredge, but at enormous cost and short-lived benefits.

Wade knew there had to be another way to keep the bar channel open and guarantee a reliable navigation channel throughout the port’s jurisdiction. In 2016, the port and the U.S. Army Corps of Engineers partnered on a demonstration program that used a hopper dredge to disperse the fluff through agitation to allow navigation. The demo was a success, and the port and the Corps began seeking an industry partner to build a first-of-its-kind vessel to work in the bar channel.

Alaska-based Brice Civil Constructors was the only company that came to the table. Brice took an offshore service vessel and modified it with jetted drag arms, a dredge pump and piping for discharging dredge material directly overboard. Jet nozzles on the drag arms stir up material on the bottom of the bar channel and block marine animals from the intakes. Fluff is then sucked up through the drag arms and pumped back over the sides of the vessel, which Brice named the “Arulaq.” Agitation dredging is considered “dredging with nature,” with winds, tides and currents dispersing material once it’s pumped overboard.

The Corps awarded a three-year, sole-source task order contract to Brice on October 30, 2018, and the Arulaq started working in the bar channel in December 2019.

Wade said it wasn’t always smooth sailing for the Arulaq in the beginning as operators worked out the kinks in the new system. Despite those early challenges, the entire team—the Corps, the port and Brice—remained committed to the project.

“The Corps could’ve pulled the plug, but they didn’t,” Wade said. “They stuck with us.”

And the results are remarkable. The Arulaq crisscrosses the bar channel 24/7. Still, the operation achieves a 75 percent reduction in fuel consumption compared to a traditional hopper or cutterhead dredge. The Arulaq dredges at a cost of 13 cents per cubic yard, Wade said, compared to $6 to $7 per cubic yard for a cutterhead dredge or $4 to $6 for a hopper.

“The cost to the American taxpayer is greatly reduced,” Wade said.

The system has worked so well that the Corps awarded a new four-year, $40 million contract to Brice in October of last year.

Once the fluff problem in the bar channel was solved, the Corps and the port were able to dredge the rest of the channel back to its authorized depth of 20 feet using more traditional means. The entire navigation channel today is at least 20 feet deep and 300 feet wide. It should be 400 feet wide by this summer, Wade said.

“And once we got the channel, all kinds of new businesses and projects began to spring up,” he said.

Those businesses include InterMoor, which designs and fabricates offshore mooring suction piles, and Patterson Tubular Services, which transports pipes to Port Fourchon by barge rather than by truck. Performance Contractors has a huge yard near Amelia where modules are built and loaded onto barges for the Venture Global facility in Plaquemines Parish. Those modules are transported offshore, then up the Mississippi River. Conrad Shipyard is building a series of Yard, Repair, Berthing and Messing (YRBM) barges for the U.S. Navy, while Bollinger is building drydocks to support the Navy’s submarine maintenance program. Space Perspective chose Conrad in Morgan City for retrofitting an Edison Chouest Offshore OSV, now called the MS Voyager, which will send space tourists to the edge of space beginning later this year.

“All of that can get in here now because our channel is open,” Wade said.

The tonnage numbers won’t necessarily reflect the huge amount of activity within the port’s jurisdiction, but for an energy and marine construction port like Morgan City, that will never be the case.

“None of this will give you the tonnage of a bulk cargo port,” said Cindy Cutrera, manager of economic development for the port. “But it’s high value. It’s not about the tonnage. It’s the traffic on our waterway that matters.”

Wade pointed to a single barge loaded with a modular component for Venture Global.

“It would take many grain barges to equal the value of that one component on that barge,” he said.

Dredging the channel offers more than just economic benefits, Wade said. Dredging in the area also has huge environmental benefits. In Bayou Chene alone, 6 million cubic yards of material was dredged last year, with 100 percent used beneficially in the surrounding marsh. In the Atchafalaya River last year, 10 million cubic yards of material was beneficially used on the west bank of the river.

“We create land,” Wade said. “We’re not washing away. And it’s a renewable resource. As long as the Mississippi River is flowing, we’re going to have sand and fluff.”

The Atchafalaya River captures 30 percent of the Mississippi River’s flow and 100 percent of the Red River.

Besides the private industry growing around Morgan City, the port itself is in the process of expanding its operations. The port’s 800-foot dock will soon grow to 1,900 feet, with available laydown space growing from 200,000 square feet to 500,000 square feet. Money for the expansion is coming from a combination of port, state and federal funds. The port’s public dock is 10 feet above sea level, with 20-plus feet of water depth for vessels, and it will offer easy connections to road and rail.

Whether attracting private industry, building new land or expanding the port’s facilities, it’s all connected, Wade said.

“It all started with dredging,” he said. “It took a lot of work and a lot of money, but we’ve got the best channel we’ve ever had, and we have opportunities now.”