Could the Baltimore bridge collapse happen in Louisiana? Here's what the experts say.
On the night of Easter Sunday 1969, the Taiwanese freighter Union Faith sliced through a crude oil barge, unleashing a towering inferno on the Mississippi River that melted steel on Experts from Louisiana have suggested that the potential for a bridge collapse similar to the collapse of the Francis Scott Key Bridge in Baltimore, which occurred in the past, is extremely unlikely due to the sheer size of the Dali, a 984-foot-long, oceangoing container vessel that was a key factor in the Baltimore collapse. The only place in Louisiana that handles ships that size is the international container terminal at the Port of New Orleans' Napoleon Avenue complex. Experts suggest that ships as large as the Dalis are not far enough to approach any bridge except the Crescent City Connection, which is the second-lowest of all Mississippi bridges between Baton Rouge and New Orleans. The industry group advocates for dredging and other steps to maintain the navigability of the Mississippi. However, Jay Hardman, executive director of the Port, Greater Baton Rouge, believes that large ships can be given multiple assistance tugboats to make the passage under bridges and that large safety measures can be in place if ships lose power or need to fall. Some experts suggest that more measures should be taken to protect the waterway from potential crashes.
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On the night of Easter Sunday 1969, the Taiwanese freighter Union Faith sliced through a crude oil barge, unleashing a towering inferno on the Mississippi River that melted steel on the Greater New Orleans Bridge and killed 26 crewmen. Nearly 25 years later, in May 1993, an errant barge and tugboat on the Industrial Canal in New Orleans took out steel support beams and caused a 145-foot section of the Claiborne Avenue bridge to collapse, killing a motorist who was five-months pregnant and seriously injuring two others. More recently, in October 2018, a towboat pushed a large crane barge into the Sunshine Bridge near Donaldsonville, damaging critical support beams. State officials concluded that the span over the Mississippi would have come down if the 1960s-era bridge had not been overbuilt.
Louisiana has experienced several spectacular, tragic waterway crashes, some of which involved bridges. But state officials and transportation experts say they are exceedingly rare. And total bridge collapses caused by a collision — like the fall of the Francis Scott Key Bridge earlier this week in Baltimore — are extremely unlikely, the experts say. A cargo ship that had lost steering power smashed into a support pillar on the famous bridge, causing the entire structure to fall down. The ship's crew was able to warn local first responders, who stopped traffic before the crash, but six construction workers on the bridge went missing. One key factor in the Baltimore collapse was the sheer size of the ship, a 984-foot-long, oceangoing container vessel called the Dali. Ships that size don't come far enough up the Mississippi River or other major Louisiana waterways to approach any bridge except for the Crescent City Connection, officials said.
"If that ship hit any bridge probably in the state of Louisiana, probably nothing could withstand it," said Chris Guidry, assistant bridge design administrator with Louisiana's Department of Transportation and Development. "The problem is that ship is not coming up the Mississippi River." The Dali, which was built in 2015, has never traveled the Mississippi, New Orleans port officials said. And its capacity of 10,000 containers matches Louisiana's maximum size for big, international cargo vessels. The only place in Louisiana that handles ships that size is the international container terminal at the Port of New Orleans' Napoleon Avenue complex, just a few blocks from Tipitina's, port spokeswoman Kimberly Curth said. Ships as big as the Dali don't go further upriver because bridges do not have a big enough "air gap," which is the vertical space ships have to pass under a bridge.
The Crescent City Connection has the second-largest air gap of bridges on the Mississippi in South Louisiana; only the Interstate 10 bridge in Baton Rouge is higher. But the next bridge upriver — the Huey P. Long Bridge in Jefferson Parish — is the second-lowest of all Mississippi bridges between Baton Rouge and New Orleans. At 20 feet lower than the Crescent City Connection, the space under the Huey P. Long blocks most container vessels from going upriver. Ships as tall as the Dali may not travel far upriver, but bulk carrier vessels that can be roughly the same weight do sometimes travel as far upriver as Donaldsonville and even Baton Rouge, according to Sean Duffy, executive director of the Big River Coalition. His industry group advocates for dredging and other steps to maintain the navigability of the Mississippi.
Jay Hardman, executive director of the Port of Greater Baton Rouge, said his section of the river routinely sees oil tankers and other bulk carriers of things such as rock that can be 850 feet long and weigh 80,000 tons fully loaded. "That's a pretty big ship," he said. By comparison, online maritime databases list the Dali's weight fully loaded at 116,000 tons. Part of the Port of Baton Rouge's roughly 4,500 feet of docks actually run under the I-10 bridge. But, like other officials, Hardman said he believed the risk of a catastrophic accident on the scale of the Key Bridge collapse was "pretty remote" because of the number of safety procedures in place. Large ships can be given multiple assist tugboats to make the passage under the I-10 bridge and when docking, he said.
"So if it loses steering or power, you've got two big assist tugs there that can push it around or keep it going where it needs to go or it will drop its anchors, but there's a lot of safety measures in place," he said. The assisting tugboats leave those ships once they pass under the I-10 bridge, Hardman said, and usually aren't in place for the next crossing downriver, the Sunshine Bridge. DOTD officials also say the piers that hold up Louisiana bridges have fenders and other measures to protect against crashes. Some experts say Louisiana should more fully examine the risk of collisions from waterway traffic. They point to the potential for more container vessels on the river, the age of some of the Mississippi's bridges and climate change's effect on river velocities.
A recent study by the Port of New Orleans suggested that ships on the Mississippi could increase in both size and number in the coming years. Norma Jean Mattei, a bridge engineer and University of New Orleans professor who served 11 years on the Mississippi River Commission, said bridge design standards beginning in the early 1990s required engineers to conduct risk analyses geared to the type of waterway traffic that can be expected to pass under a specific bridge. But the Key Bridge in Baltimore and several lower Mississippi bridges were all built years before those standards were in place, Mattei said, including the Hale Boggs Memorial Bridge and both Crescent City Connection bridges. The I-10 bridge in Baton Rouge was built in 1968. "Many of those bridges more than likely have never had a risk assessment done to the level of the specifications when it comes to vessel collision," she said during a new conference Thursday for an association of U.S. cities along the Mississippi.
Mattei suggested those analyses could be limited to bridges where the size of ships has or could be expected to significantly increase, primarily from container traffic. DOTD officials said they continually examine bridge safety in light of changing bridge conditions. The Port of New Orleans is currently seeking permits to build a new $1.8 billion Louisiana International Terminal in Violet, 17 miles downriver from the nearest bridge. Curth said the air-gap restrictions under the Mississippi bridges are why the port is pursing the terminal, though it has encountered opposition from St. Bernard residents who have questioned its safety for other reasons. Construction is expected next year and the facility is expected to open in 2028, she said.
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