The US National Transportation Safety Board has released an investigation report detailing a marine accident where a towing vessel collided with a bridge in Louisiana.
On June 6, 2024, at 05:12, the 55.2-foot-long (16.8 metres) towing vessel Josset was pushing three barges when the lead vessel struck the swing span of the Bayou Grosse Tête Bridge.
Although none of the five crew members sustained injuries and no environmental pollution was reported, the incident caused an estimated $2.5 million in damage to the structure.
The bridge, which carries a two-lane highway and accommodates an average of 5,000 vehicle trips daily, was forced out of service for 110 days.
Operating under C & J Marine Services, the Josset departed the vicinity of Bayou Pigeon on June 5, 2024, at approximately 22:00, pushing two loaded hopper barges and one empty tank barge. The total length of the transiting tow measured 692 feet (210.9 metres), with the empty tank barge FMT 502 positioned at the front of the line.
Around 00:00 on June 6, a contract pilot took over watch and navigated the vessel through the Bayou Sorrell Lock at 02:00 without encountering any issues.
As the tow approached the Bayou Grosse Tête Bridge at 04:52, darkness and a bend in the waterway approximately 0.5 miles (0.8 kilometres) south of the structure limited visibility.
The pilot radioed the bridge tender from a distance of one mile (1.6 kilometres) to request an opening, prompting the worker to ask for a second contact when the vessel drew closer.
Relying on automatic identification system data that only recorded the length of the towboat, the bridge tender then temporarily left the station to use an adjacent restroom, which meant the 637 feet (194.2 metres) of forward barges went unaccounted for.
When the pilot made the second call at 05:02 from a distance of 0.4 miles (0.6 kilometres), the bridge tender instructed the vessel to proceed, erroneously assuming the swing span would be open in time. Upon realizing the bridge remained closed, the pilot attempted to reverse the vessel, but the tow maintained headway and collided with the partially opened swing span at 05:12.
The empty tank barge, FMT 502, sustained a six- to eight-inch-long (15.2 to 20.3 centimetres) scrape during the impact. To assist local residents during the 110-day repair period, Iberville Parish officials established a temporary passenger ferry service.
Investigators determined that the bridge tender miscalculated the proximity of the tow because the automatic identification system did not broadcast the full length of the barges. Furthermore, the pilot chose not to station a crew member at the head of the tow to serve as a lookout, which prevented early detection of the closed bridge.
The federal safety agency concluded that the primary cause of the collision was the bridge tender's failure to initiate the opening sequence in a timely manner. A lack of an active lookout on the lead barge was also cited as a contributing factor that prevented the pilot from stopping the vessel in time.