NTSB Identifies Loose Wire as Cause of Baltimore Bridge Collapse

A single loose wire in the electrical system of the Dali cargo ship caused two power blackouts, leading to the vessel's loss of propulsion and steering before it collided with Baltimore's Francis Scott Key Bridge on March 26, 2024, according to the National Transportation Safety Board (NTSB). The impact resulted in the bridge's collapse and the deaths of six construction workers.

NTSB Chair Jennifer Homendy emphasized the preventable nature of the disaster, noting that the workers were not warned about the ship's emergency before the collapse. The investigation also revealed that the crew had insufficient time to recover propulsion and avoid the collision due to the ship's proximity to the bridge when it lost power.

In response to the incident, the NTSB has recommended that 68 bridges across 19 states undergo vulnerability assessments to determine their risk of collapse from vessel collisions. These bridges were designed before 1991 and have not been evaluated under current standards.

Maryland officials have updated the estimated cost to replace the collapsed bridge to between $4.3 billion and $5.2 billion, with an anticipated completion date in late 2030. This is a significant increase from the previous estimate of $1.9 billion and a 2028 completion date.