NTSB cites lack of ‘decision point’ in Atchafalaya bridge strike
Edna T. Gattle and the spud barge Terral 2 approached the Union Pacific Railway Bridge over the Atchafalaya River when the towboat’s captain requested the swing bridge open. Twenty-one minutes later, as the tow came within a half mile of the span, it was still closed.
The captain backed down and moved several hundred feet upriver against a current that set the tow to starboard. The bridge opened, and he made a new approach from a position closer to the right bank than his first attempt.
The captain lost control of the tow and the 200-foot Terral 2 hit the bridge in several places at about 2348 on April 24, 2019. The bridge, at mile 41.5 near Krotz Springs, La., closed to rail traffic for three days and required $500,000 in repairs. No one was injured and no pollution was reported.
The National Transportation Safety Board (NTSB) acknowledged the bridge took longer than average to open. But investigators also determined the captain should have established a “decision point” to slow down or stop if the bridge remained closed.
“Since (vessel operator Terral River Service) did not include decision points in their operations procedures for the Union Pacific Railway Bridge transit, the captain did not have a set location to stop and reassess the approach to the bridge once he realized that the bridge would not be open in time for his transit as initially planned,” the NTSB said in its report. “Had the captain slowed or stopped earlier at a planned and specified decision point before the bridge, he would have had more time and distance to make his second approach correctly.”
Terral River Service, based in Lake Providence, La., did not respond to an inquiry about the NTSB findings.
Edna T. Gattle, a 3,000-hp retracting pilothouse towboat, picked up Terral 2 in Simmesport, La., at 1920 for a transit to Amelia, La. The spud barge had an excavator on deck, and its vertical clearance was 45 feet. The Union Pacific bridge had less than 26 feet of clearance.
The captain contacted the bridge tender at 2307 to request the span to open. He tried again a few minutes later when the tow was 3 miles from the bridge making 15 mph over land. There was a delay in the span opening while the tender awaited approval from a supervisor.
The tow reached the U.S. 190 highway bridge, about half a mile from the railroad bridge, at 2328. The rail bridge was still closed. The captain slowed down to about 7.5 mph and again contacted the bridge tender, who told him to stand by. The captain backed the tow when it became clear the bridge would not open in time. The current near the bridge was moving close to 5 mph.
The current set the tow to starboard, and the captain began his second approach roughly 150 feet closer to the right bank than the aborted first attempt. As a result, the NTSB determined, the second approach starting at about 2345 came at a much steeper angle.
Terral 2 struck the bridge three minutes later. Its starboard quarter first hit a bridge pier before bouncing to port and hitting the swing span pedestal. The excavator also hit the swing span.
“The tow, propelled by current, forward momentum and a large eddy on the downriver side of the pedestal, forced the bridge to move in a counterclockwise motion, almost back to its closed position,” the report said.
Terral 2 took on water from several fractures and holes caused by the impact, although the crew used pumps to address the flooding. The barge required close to $27,000 in repairs. The bridge’s locking mechanism was damaged, preventing the span from closing.
The bridge is in an area known for swift, challenging currents, and it has been hit several times over the years — including by an Edna T. Gattle tow in 2014. Barges pushed by Marguerite L. Terral, a sister vessel to Edna T. Gattle, hit the span in 2017. The NTSB determined the bridge tender in that case was distracted and failed to open the bridge in a timely manner.
In the April 2019 case involving Edna T. Gattle, the bridge took 27 minutes to open. The previous month’s average time to open the span was about 18 minutes. The NTSB determined 27 minutes was not particularly unusual.
“Though the bridge was slower to open than average,” the NTSB concluded, “the captain and company should have anticipated such contingencies and planned mitigating actions, especially given the higher-than-normal river current.”