Morgan City Has Innovative Dredge Plan For Bar Channel

Demonstration project in 2016 showed that agitating the channel could produce adequate depths for navigation.
Demonstration project in 2016 showed that agitating the channel could produce adequate depths for navigation. (File photo by Frank McCormack)

The Port of Morgan City, located at the intersection of the Gulf Intracoastal Waterway (GIWW) and the Atchafalaya River, sits at a prime location for waterborne commerce. Vessels traveling between the Mississippi River and the GIWW can opt for the Atchafalaya, which flows out of the Mississippi via the Old River Control Structure some 140 miles north of Morgan City. By taking the Port Allen Route, vessels can bypass New Orleans altogether.

And at an authorized depth of 20 feet, the bar channel, the 10- to 12-mile offshore stretch of the port’s navigation channel leading from the Gulf of Mexico ought to make Morgan City an attractive port of call for smaller ocean carriers hoping to save the time, fuel and fees associated with traveling all the way up the Mississippi to New Orleans.

“Ought to” being the key phrase.

That’s because it’s been a while since the bar channel has been consistently maintained at its authorized depth of 20 feet due to a constant buildup of fluff, a soupy type of silt that has hampered oceangoing ship traffic at the port.

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When the bar channel was last dredged to 20 feet in October 2014, the draft lasted only a few months. By the following March, the draft in the bar channel was down to 16 feet. By mid 2015, the draft had dropped to 14 feet or less. That rapid filling in of the fluff cost the Port of Morgan City its import/export business, with the last ship calling in March of 2015.

Traditional dredging in the bar channel is simply ineffective and too expensive for clearing out the fluff, which Port of Morgan City Executive Director Mac Wade has described as “fluid mud.” And with high water from the Red and Mississippi rivers depositing sediment just below the Port of Morgan City each year, scarce Corps funding has gone to clearing the river channel, which, unlike the bar channel, maintains its depth for longer periods.

But after a taste of being an import/export destination and with key shipbuilding facilities nearby, Port of Morgan City officials refused to give up on maintaining the bar channel at 20 feet.

Jump to the summer of 2016, when the Port of Morgan City and the U.S. Army Corps of Engineers partnered on a demonstration project to see if simply agitating within the bar channel would disperse the fluff and drop the water density below 1,200 milligrams per liter, which is a benchmark for safe navigation. Manson Construction got the job and sent the hopper dredge Newport to the bar channel, where it worked from June 4 to August 15, 2016. Instead of dredging the channel and filling the hopper with sediment, the Newport simply pulled the fluff-filled water onboard and immediately sent it overboard, essentially agitating the channel. In short order, the effort worked. The constant agitation in the bar channel dropped the fluff line from 9-1/2 feet all the way down to 18 or 19 feet (for the demo, 18 feet was the target). The Corps released a draft report in December 2016 stating that short-term results, at least, indicated agitation dredging was a cost effective means for clearing the fluff.

And now, more than a year after the Corps draft report on the demo, the Port of Morgan City is poised to see agitation in the bar channel used as a longterm strategy for maintaining a 20-foot channel.

“Based upon a review of the alternatives and supported by a demonstration project completed in late 2016, the port and the Corps have concluded that agitation dredging and sediment conditioning is the dredging protocol most likely to achieve a year-round navigable 20-foot-deep bar channel within the available funding,” the Corps said in a statement. “The Corps is currently on track to award a contract for the services of a special-purpose dredge to perform agitation dredging and sediment conditioning beginning in the fall of 2018.”

At a recent industry day, one company stepped forward and expressed an interest in constructing a purpose-built dredge for working in the Atchafalaya bar channel. In an effort to cement the company’s willingness to do the job, the Port of Morgan City went so far as to enter into a cooperative endeavor agreement with the company. According to the terms, the company purchased a special pump for the task, even though the contract has not yet been awarded. If for some reason the contract falls through, the Port of Morgan City has agreed buy the pump from the company.

“We wanted them to get that pump ordered so that, when they’re given the order to proceed, they will be very close to completing their equipment and being ready to work,” Wade said. “They ordered the pump in January.” The port did not name the company, pending final execution of the contract.

Cindy Cutrera, economic development manager for the Port of Morgan City, said the port also has a memorandum of understanding in place with the Corps to provide up to $1.25 million in fiscal year 2018 to complete dredging in the river channel after high water passes. Doing that could mean there’s enough funding in the budget to get started on the bar channel in 2018, but it also means the port won’t have to dip into fiscal year 2019 funds to tackle shoaling in the river channel. The funding picture for the port really looks positive, too, with funding set to jump from $6.3 million to $12.675 million in fiscal year 2019.

“We think we will see them in the bar channel by the last quarter of the year,” Cutrera said. “All they need once they complete negotiations is the notice to proceed. The Port of Morgan City is looking forward to having a reliable, navigable channel by the end of the year.”

Cutrera credited Gen. Richard Kaiser, commander of the Corps’ Mississippi Valley Division and president of the Mississippi River Commission, with being willing to look at the Port of Morgan City’s dredge and tonnage issues and to work with the port on a solution.

“He really gets it,” Cutrera said.

With funding for channel maintenance based on tonnage, ports like Morgan City often struggle to have the value of cargoes passing through them accounted for in the Corps’ budgeting process.

“It just hasn’t worked for a port like ours,” Cutrera said of the funding mechanism. “With all of the shipbuilding and fabrication of components that go offshore to supply the energy business, the value of those components they’re building far exceeds what a barge load of grain would be worth.

“We’re trying to show where our worth is, and they’ve been listening,” she said.

Now on the cusp of putting a plan in action to keep the bar channel offshore dredged for the foreseeable future, Wade said he hopes the port will see cargo tonnage go up very soon.

“If we can keep this level of funding going for the next three to five years, we should have a very vibrant port, and with the import/export business, we’ll have those tonnage numbers,” Wade said. “That’s what we asking: Just give us a shot. We are worth the investment.”