On June 22, 2020, about 0230 local time, the deck cargo barge Ho'omaka Hou was under tow by the towing vessel Hoku Loa off the northeast coast of the big island of Hawaii en route to Hilo, when fifty 40-foot containers stacked on the after deck of the barge toppled, causing 21 to fall into the ocean. There were no injuries or pollution reported. Eight containers were eventually recovered by salvors, and 13 remain missing. Cargo loss was estimated at $1.5 million, and damage to the barge and containers was estimated at $131,000.
The probable cause of the collapse of container stacks onboard the barge Ho'omaka Hou towed by the Hoku Loa was the company not providing the barge team with an initial barge load plan, as well as inadequate procedures for monitoring stack weights, which led to undetected reverse stratification of container stacks that subjected the stacks' securing arrangements to increased forces while in transit at sea.
Sufficiency of Container-Securing Arrangements on Barges
It is important for cargo planners to have tools, such as stow plans and calculations, to assist with determining proper stowage and the sufficiency of securing arrangements for containers stacked on barges. These tools should address the potential that container stacks may be stacked in a reverse stratified manner.