Cargo Ships Have Now Become Supersized

"When the Key Bridge was built in 1977 across the harbor of Baltimore, the biggest cargo vessels that sailed into the port carried 2,000 or 3,000 shipping containers.

The Dali was loaded with about 4,700 40-foot shipping containers when it slammed into the bridge, destroying the steel structure and killing six people. It was nearly full. It was built in 2015 to hold the equivalent of nearly 10,000 20-foot equivalent units, or TEUs, a standard measure of capacity.

The Dali isn't the first cargo ship to topple a U.S. bridge. The Summit Venture struck the Sunshine Skyway Bridge near Tampa, Fla., in 1980, collapsing a section of the span and killing 35 people. The bridge was replaced and a complex system of buoys and monitors was added to help guard the new span from a potential ship strike.

Ocean vessels have become supersize in recent decades as owners sought to reduce costs, lower fuel emissions and maximize capacity on the most popular routes.

The expansion of the Panama Canal in 2016 made it possible for bigger ships to cross from Asia to the U.S. East Coast. The Dali, which is 158-feet wide and 984-feet long, is designed to be just big enough to fit through the expanded canal and unload in a port like Baltimore.

The Dali, however, is dwarfed by ultralarge containerships that can hold nearly 15,000 TEUs and connect Asia and the California ports of Los Angeles and Long Beach. Those ships are too big for the Panama Canal or Baltimore's port.

Maersk, which chartered the Dali on its latest voyage, set off the boat race. In 2013, the shipping line introduced a new generation of ultralarge ships with capacity for 20,000 TEUs.

Shipyards in China and Korea have been competing since to pump out the biggest boats for a once-fragmented industry that has consolidated to a handful of shipping lines dominating the seas. The current record holder, the MSC Irina, can carry roughly 24,000 TEUs and is 1,312-feet long.

These vessels require big shipping channels, large berths and supersize cranes that only the biggest ports own. Some U.S. ports have responded in recent years by raising or replacing bridges to accommodate bigger boats." [1]

1.  U.S. News: Cargo Ships Have Now Become Supersized. Mcgill, Brian; Champelli, Peter; Paris, Costas.  Wall Street Journal, Eastern edition; New York, N.Y.. 01 Apr 2024: A.3.