Carlo Ratti Unveils Proposal for Key Bridge Replacement

At approximately 1:30 am on March 26, 2024, a cargo ship left the Port of Baltimore, lost power, and struck a main pier of the Francis Scott Key Bridge, causing the span to collapse and kill six construction workers who were on the bridge at the time. Removal of the wreckage has been ongoing since, with the body of a fifth missing construction worker found last week. The National Transportation Safety Board is supposed to release a preliminary investigation on the collapse later this month, and authorities are exploring how to rebuild the bridge and resume regular access to the port. President Joe Biden has pledged that the federal government would pay to rebuild the bridge, with initial estimates approaching $2 billion.

Also last week came news that Italian construction company Webuild, which rebuilt the Morandi Bridge in Genoa after it collapsed, would be pitching a proposal for “a cable-stayed bridge with the aim to improve safety, adaptability, sustainability and to ensure maximum safety for navigation.” The proposal would need to address the deficiencies of its predecessor, primarily lengthening the span so the piers would not be within the main channel. While the larger Key Bridge, which opened in 1977, was 8,636 feet (2,632m) long, spanning the Patapsco River in Baltimore, the main steel-truss span over the river's navigable channel was 2,644 feet (806m) and the main span was even shorter, at 1,200 feet (366m). 

Comparing the rendering at top to the above photograph of the bridge, it's clear that the proposal by Carlo Ratti Associati and Michel Virlogeux for Webuild has a considerably longer span, courtesy of the cable-stay structure. Instead of 1,200 feet (366m) between piers, their proposal spans 2,230 ft (700 m), effectively moving the bridges piers into shallow water, at a remove from the navigation channel used by large vessels going in and out of the port. The proposal also adds one lane of traffic in each direction; before the collapse, the roadway (part of Interstate 695) would handle approximately 30,000 vehicles each day.

At this point, there is not guarantee that Webuild's proposal will be adopted for the rebuilding of the Francis Scott Key Bridge in Baltimore; other proposals will most likely be submitted in the coming months. As of recent reports, the State of Maryland is planning to complete the new span by fall of 2028.