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Francis Scott Key Bridge collapse

2024 bridge collapse near Baltimore, Maryland, US

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Through Steel, Atlantic Ocean and Coal

The collapse blocked most shipping to and from the Port of Baltimore for 11 weeks. Maryland Governor Wes Moore called the event a "global crisis" that affected more than 8,000 jobs. The economic impact of the closure of the waterway was estimated at $15 million per day.

Maryland officials have said they plan to replace the bridge by late 2030; initial cost estimates of $1.7 billion to $1.9 billion were later revised to $4.3 billion to $5.2 billion.

Background

The Francis Scott Key Bridge was a steel arch-shaped continuous truss bridge, the second-longest in the United States and third-longest in the world. Opened in 1977, the 1.6-mile (2.6 km; 1.4 nmi) bridge ran northeast from Hawkins Point, Baltimore, to Sollers Point in Dundalk in Baltimore County, Maryland. Before being damaged, it carried Interstate 695, a beltway around Baltimore; its four lanes (two in each direction) were used by some 34,000 vehicles each day, including 3,000 trucks, many of which hauled hazardous materials barred from the two harbor tunnels.

The bridge crossed one of the busiest shipping routes in the United States: the lower Patapsco River, which connects the Port of Baltimore to the Chesapeake Bay and the Atlantic Ocean. In 2023, the port handled more than 444,000 passengers and 52.3 million tons of foreign cargo valued at $80 billion. It was the second-largest U.S. port for coal, and had been the leading port for automobiles and light trucks for 13 straight years, handling more than 847,000 vehicles in 2023. It employed 15,000 people and indirectly supported 140,000 others, annually helping to generate $3.3 billion in wages and salaries, $2.6 billion in business revenue, and $400 million in state and local tax revenue.

MV Dali is a container ship registered in Singapore, and at the time of the collision was operated by Synergy Marine Group and owned by Grace Ocean Private Ltd, both based in Singapore. A Neopanamax vessel completed in 2015, Dali has a length of 980 feet (300 m), a 157-foot (48 m) beam, and a 40-foot (12.2 m) draft. Danish shipping company Maersk chartered Dali upon its delivery. Once in service, Dali underwent 27 inspections at ports globally, including two in 2023: one in June in San Antonio, Chile, where a fuel-pressure gauge was repaired, and the second in September by the U.S. Coast Guard in New York, which found no problems.

In March 2024, Dali was crewed by 20 Indian nationals and one Sri Lankan. The ship traveled from Panama to New York, arriving on March 19, then sailed to the Virginia International Gateway in Portsmouth, Virginia. The ship left Virginia on March 22 and the following day arrived in Baltimore, where it underwent engine maintenance. An anonymous source told the Associated Press that an alarm on the ship's refrigerated containers went off while the ship was docked, likely due to an inconsistent power supply.

When the bridge was completed in 1977, the largest container ships could hold 2,000 to 3,000 twenty-foot equivalent unit (TEU) containers. In the 2000s, the governments of Maryland and Baltimore, which relied on port operations to replace lost manufacturing jobs, seized the opportunity provided by the Panama Canal's expansion: they installed new cranes and dredged the harbor to accommodate the up-to-14,000-TEU vessels that began passing through the canal in 2016. At the time of its collision, Dali was loaded nearly to its 10,000-TEU capacity with 4,700 forty-foot containers.

In 1980, a ship roughly one-third the size of Dali struck and lightly damaged one of the bridge's piers. After the bridge collapsed in 2024, anonymous former agency officials told The Washington Post that the Maryland Transportation Authority (MDTA) did not consider studying the possibility of a collision with a larger ship, and instead spent decades studying how terrorists might attack the bridge after the September 11 attacks or inspecting for structural flaws similar to those that caused the I-35W Mississippi River bridge collapse in 2007. In 2018, the World Association for Waterborne Transport Infrastructure noted that ships frequently hit bridges but rarely destroy them; between 1960 and 2015, thousands of barges and ships collided with U.S. bridges, destroying 18 of them.

Federal regulations require national highway bridges to conform to standards established by the American Association of State Highway and Transportation Officials, but AASHTO did not specify how strong bridges should be to withstand ship collisions until 1994. Federal regulations for bridge protection systems from ship collisions were updated in 1991 after the Sunshine Skyway Bridge collapse in 1980, but existing bridges were exempted by a grandfather clause, and the Francis Scott Key Bridge piers lacked the level of fender system or island barriers required of newer bridges. However, engineering experts debate whether such bridge protection systems could have prevented the collapse, given Dali's size. The preliminary National Transportation Safety Board (NTSB) report noted that inspections conducted in March 2021 and May 2023 to National Bridge Inspection Standards found the bridge in satisfactory condition.

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