The fog was so heavy the morning the Cosco Busan struck the Bay Bridge that at least four other large vessels decided to wait until it cleared, the Coast Guard said Thursday.
A preliminary assessment by the Coast Guard of the causes of the crash concludes that the decision of those in charge of the container ship to set sail in dense fog played a key role in the Nov. 7 accident, which spilled 53,000 gallons of fuel oil into the bay, fouling miles of Bay Area and ocean shoreline and killing thousands of birds.