The river bend above Luling, Louisiana looks calm enough from a bridge railing.
Underneath, the current was running about 6 mph that night.
A towboat pushing 29 loaded grain barges was sliding downstream toward it.
Its pilot reached for a maneuver river pilots have long used in fast water.
It did not leave the tow where he needed it.
What happened next came down to a single choice, whether to move a 1,195 foot tow sideways with the rudders or with the throttles.
Flanking is the river maneuver that sets a big tow up for a bend like this one
Towboat pilots call it flanking, and it is built around using the river rather than fighting it. Investigators describe the technique plainly: the operator reverses the engines to cut the tow’s forward speed and puts the stern toward the point, or inside, of the bend, so the current walks the barges around the curve.
It is possible only when the current is pushing the vessel from astern. That is the setup the pilot used for the left hand bend known as 26 Mile Point, a short distance above the span that connects Destrehan and Luling.
The river was running high, near flood stage on the local gauge. A high river on the Lower Mississippi is a fast one, and flanking buys steering control by giving up speed, which is what a pilot wants before threading a tow of that size between bridge piers.
But a flanked tow still has to come out of the bend lined up with the channel. Once this one emerged set toward the eastern tower pier, the pilot had to shift 29 loaded barges sideways, quickly, with the current shoving from behind.
A fast current met a tow that answered with engine power instead
Instead of working the rudders hard, the pilot reached for the throttles. According to the accident brief, he chose primarily to use increased engine speed in an effort to move the tow to starboard, away from the pier, telling investigators he “tried to outrun” the current.
Video evidence showed he used limited rudder as the tow closed on the span. That is the heart of the story.
Adding power to a loaded tow does not push it sideways. The report found the tow’s course over ground did not appreciably change as engine speed increased, while the added speed over ground cut down the time left to maneuver.
The tow struck the eastern tower pier at 11.9 mph. The probable cause, investigators determined, was the pilot not effectively compensating for the strong current while navigating the turn and approaching the bridge in high water conditions.
The tow broke apart near mile marker 121 and one barge went down
The impact landed on the port side of the tow, at mile 121.6, and it did not stay confined to the barges that absorbed it. The tow broke apart and began floating downriver, with the barges ART1008 and ART44080B named alongside the towing vessel in the accident brief.
One barge sank. The towboat and other vessels that responded rounded up the rest, but not before drifting barges contacted barges moored along the banks.
Two barges were written off as constructive total losses, and the estimated cost of damage to barges and cargo came to about $1.65 million. The investigation of the March 15, 2020 contact drew on electronic charting system data, onboard video and interviews with the pilot.
A loaded bulk carrier passed upbound minutes before the bend
Shortly before the contact, the tow had company in the channel. At 0052 the Cooperative Spirit tow met the upbound bulk carrier Ikan Parang at mile 124.2, a few miles upriver from the bridge, and after passing the bulker the pilot began setting up for the bend.
The flanking maneuver itself ran from 0055 to 0108, finishing under a mile upriver from the span. That left only minutes, and barely any distance, to settle the tow into line for the bridge opening.
None of that is unusual on the Lower Mississippi, where barge traffic and oceangoing ships share a single channel. It shows how little room the sequence allowed, much like the split second maneuvering a tug crew faced off Point Judith.
No one was hurt, and the bridge itself came through intact
For all the force involved, the damage stayed on the water. No injuries and no pollution were reported, and the Coast Guard reported no damage to the bridge from the strike.
The channel did not reopen quickly. The Coast Guard closed the Lower Mississippi between miles 115 and 122 while barges were recovered and inspectors checked the span.
The river reopened to navigation the following afternoon, more than a day after the contact. Flanking remains the standard way to bring a big tow around a tight Mississippi bend.
What the report underlines is the limit of the alternative, because once a loaded tow is already set toward a pier, more power mostly means arriving sooner, the same way crews plan carefully before they reroute an oversize load rather than force a path with no margin. The pier held, the barges were salvaged, and the next tow through that bend will meet the same current.
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