While loading its cargo in Convent, La., in March 2023, the bulk carrier Sirocco broke free from its moorings and was swept down the Mississippi River in a 4-knot current. Several tugs scrambled to wrangle the drifting 751-foot bulker, which had dropped both anchors and engaged its engine, but Sirocco eventually struck a moored barge downriver.
No injuries or pollution were reported from the March 27, 2023, incident. The total damage to Sirocco, the barge and a dock was estimated at $5 million.
Federal investigators said that as coal was loaded into Sirocco’s forward holds, an increased area of the vessel’s underwater hull was exposed to the strong river current, “leading to continuously strengthening forces pushing the vessel off the dock [and] increasing tension in the lines,” the National Transportation Safety Board (NTSB) said in a report. Examination of Sirocco’s bow winches found extreme heat and friction marks. “The company reported that the failure was from the mooring lines running out at high speed, causing excessive heat and vibration that damaged the brake mechanism,”
On March 26, 2023, the Panamanian-flagged Sirocco docked – its bow pointed upriver and into the current – at Convent Marine Terminal (CMT), located at mile 160 on the Lower Mississippi River. The master ordered 16 lines to secure Sirocco, with four head and four stern lines, two forward and aft spring lines, and two forward and after breast lines, “all placed according to the CMT’s high-water loading plan,” the NTSB report said.
That plan was established in 2015 after another bulk carrier broke free from its moorings at CMT. The cause was determined to be an inadequate mooring arrangement and insufficient hold-in tugs provided by the vessel operator, the NTSB said in its report on Sirocco. When the Carrollton Gauge, the standard reference for the height of the Mississippi River, falls below 12 feet, “the high-water loading plan [is] no longer in effect, and therefore CMT did not require hold-in tugs,” the NTSB report said.
As the port captain boarded the Sirocco around 1230 on March 26, the Carrollton Gauge was at 11.8 feet and falling, thus negating the high-water plan. The port captain asked the master of Sirocco to release the aft tug, which was let go at 1315, the NTSB said in its report. “At 1408, the ship’s agent emailed the master of the Sirocco, stating ‘the terminal no longer requires your vessel to have any hold-in tugs alongside.’ The port captain requested the forward tug be released, stating that it is ‘normal practice to keep such size vessel alongside without any holding tug.’” The port captain explained to investigators that the charterer paid the cost for hold-in tugs when CMT’s high-water loading plan was in effect, but otherwise, the cost would be charged to the vessel’s owner.
“The master later told investigators that he was surprised that hold-in tugs were no longer required, given the strength of the river current,” the report read. “The forward tug was let go at 1500.” Sirocco was set to be loaded with more than 73,000 tons of coal in all seven of its cargo holds while moored at CMT.
Between 1500 and 1650, the port captain twice noticed slack lines on the stern of Sirocco and reminded the master to heave the lines, which the master communicated to the crew. “In addition to tending the lines, watchstanders also had cargo operation duties, such as cleaning hatch tracks, taking tank soundings, closing cargo hatches, and gangway security watch. The second officer stated that during his watch, the AB made rounds about every 20 minutes to check the forward and aft mooring lines. Loading operations continued throughout the remainder of the day on March 26,” the NTSB report said.
Around 0150 on March 27, the second officer noted that the bow had moved away from the dock by nearly five feet. The breast lines were so tight that the crew “were not able to heave them in with the vessel’s electrohydraulic mooring winches,” the report said.
The master went to the bridge at 0201 and called for immediate tug assistance. At 0210, the second officer observed all the forward mooring lines paying out and “saw smoke and sparks from the portside winches,” the report said. The master informed the engine room that he needed the engine immediately.
As Sirocco’s bow moved out into the Mississippi River, an aft breast and aft spring line parted and dangled over the vessel’s starboard side; all other lines remained secured on the bollards at the dock, the report said. Sirocco broke away from the dock around 0213.
The master ordered the on-watch deck crewmembers to let go of the anchors. The starboard anchor dropped at 0220 and the port anchor at 0222, just as two tugs, Savannah and South Carolina, arrived. Main engine propulsion control was transferred to the bridge at 0216. “After ensuring there were no lines endangering the propeller, the master began using the ship’s main engine propulsion at various ahead and stop propulsion orders,” the NTSB said.
“At 0248, the bulker was drifting downriver about 4 knots and closing on the Mosaic Uncle Sam dock on the left descending bank, where three barges were moored alongside each other. Both tugs continued efforts to stop the vessel’s drift downstream,” the report said. Savannah’s crew used their whistle to warn workers at the Mosaic Uncle Sam dock of the impending collision. Footage shows workers evacuating.
At 0249, Sirocco’s starboard quarter struck the port side of a barge, “then drifted aft against the barge before the vessel stopped and moved ahead and away, using the main engine and the tugs,” the report said.
Sirocco eventually maneuvered into the middle of the river where it was met by a third tug, Elizabeth B, around 0300. A pilot came on board at 0305, all lines were recovered at 0355, and both anchors were heaved up and secured by 0430, the NTSB said. The pilot maneuvered Sirocco to the Grandview anchorage, near mile 147, around 0600. By 0712, the vessel was secured with both anchors.
Pilings and multiple beams supporting the Mosaic Uncle Sam dock were pushed out of position, and the dock’s concrete surface was damaged. The barge struck during the allision was considered a total constructive loss.
In early 2024, there were a series of near-miss incidents on the lower Mississippi, near CMT, including back-to-back days in March when tugs came to the assistance of a vessel out of control, according to reporting from Maritime Executive. Convent Marine Terminal did not respond to questions about the Sirocco incident or if its high-water plan has since been amended.