On March 26, 2024, disaster struck Baltimore as the cargo ship Dali crashed into a pier of the Francis Scott Key Bridge, causing a devastating collapse. Six maintenance workers were lost – two bodies recovered, four presumed dead. The economic fallout was staggering, as the bridge closure choked off the Port of Baltimore, costing upwards of $15 million per day and heavily impacting regional jobs.

The bridge, built in 1977, was an monumental engineering structure and a vital artery connecting Baltimore to surrounding areas. The Dali, although reported recently and regularly undergoing inspections, suffered a power outage, drifted off course despite the harbor pilots on board. Emergency measures failed, and despite desperate efforts, the collision triggered a tragedy.
Without being able to assess the reasons leading to this event, some thoughts on reducing risks and hopefully eliminating such events in the future come to mind.

To prevent disastrous ship collisions with bridges, a multi-pronged approach is necessary. For ships, advanced navigation systems incorporating back-up power systems, sophisticated GPS tracking, real-time hazard mapping, and AI-powered guidance will decrease collision risks, especially in congested waterways or poor visibility. Robust bridge design is paramount, with (a) piers able to withstand the impact of vessels – nowadays with a rapidly increasing tonnage – and (b) structures designed with redundancy measures to allow for load transfer in case of damage. Even further, some bridges may be designed to allow for controlled deformation in extreme events to maintain stability. On the other hand, robust fender systems can be installed to absorb impact forces, and dolphins (protective structures around piers) act as sacrificial barriers to deflect errant ships, protecting bridge piers. Rigorous inspections, coupled with sensor monitoring, will proactively identify hidden damage or weak points before they become critical. These can be related to corrosion in structural and reinforcing steel, cracking or even scour at the foundations. Finally, when planning major crossings, considering tunnels as an alternative can eliminate risks posed by ship traffic, and provide resilience against extreme weather and deterioration that affect exposed bridges.