Silent and stealthy they floatJan 1, 2003
|From Ocean Navigator #62 |
The answer is yes and no. Containers do fall overboard. But many of them sink fairly quickly and the chances are actually quite slim of a vessel finding itself on the same spot of ocean with one of those containers.
"It just doesn't happen very often, but it still happens more than it should," said Sam Bhalla, a cargo surveyor in New Jersey. "When a container is lost overboard on a large vessel, usually bad weather or faulty lashings are to blame. Everyone is aware of the problem, and no one wants it to happen to them."
Of course, most modern ships would be unable to recover lost containers from over the side, so these errant steel boxes may spend a number of hours, days or even weeks floating partially or completely submerged. Some even end up spilling their contents onto shorelines, much to the delight or dismay (depending on the box's contents) of local inhabitants.
Steve McGowan, a licensed delivery skipper, reports that he saw two containers floating on recent voyages between the East Coast and Bermuda. "I saw one in calm weather about 200 miles east of Charleston. It was floating with probably an inch showing above the surface. We spotted it and circled it, but there was nothing we could do, so we went on," he said.
"The other one I saw was in rough weather," said McGowan. "We had heard nothing about it over the radio, and the fellow on watch spotted it floating with only one corner showing." But, McGowan does not feel that the chances of hitting a container are very large. "I don't think it is a big problem. It just demonstrates the necessity of a good watch. We used to be particularly aware of it after a big storm."
More recently, the skipper of the American yacht Heather Maria, which sank in a storm off the Australian coast in April, said he believes he hit a shipping container hours before the sinking.
Patrick Waddick, 66, of San Diego, said he heard a "loud thump" the night before his vessel sank about 300 miles off Brisbane. Shortly after dawn he dove over the side and found a "wedge shaped" hole in the hull, just as one would expect from the edge of a shipping container.
In the past several months, several container losses have come into the public eye.
· In mid-February, 21 containers were swept from the Bahamian-registered Marine Trader. Four contained chemicals, one was loaded with crockery and the other 16 were empty. German salvors collected six of the empty containers floating in the North Sea, but the rest sank.
·The Military Sealift Command container vessel Giovanna lost 10 containers and reported them floating in the North Atlantic off the southwest tip of Ireland in late March.
·Ten containers fell overboard from the vessel Kamina in early April, three of which collectively contained 54 tons of cyanide. Those containers immediately sank, off the coast of Chile.
· On May 3rd, the 21,475-gross-ton container vessel Thompson Lykes lost three 40-foot containers in heavy seas at 46° 18' N, 19° 12' W. The containers were reported to be possibly afloat and adrift.
Last October, a barge carrying 170 containers through Buzzards Bay, Mass., lost 34 of them to heavy seas and high winds. The accident became something of a joke to local residents who happily combed the beaches collecting sneakers and rubber ducks.
Containers can and do fall overboard when even the most modern vessels are involved in collisions. For example, the huge containership President Washington, operated by American President Lines, was involved in a collision off the Korean coast in May. Early reports indicated that as many as 30 containers were knocked into the water. Some containers were also projected onto the deck of the other ship, a South Korean-flagged container vessel. Since neither vessel was capable of recovering those containers, and both were fully involved in damage control efforts, the 20-foot steel boxes were most likely left to their fate. That accident, which occurred on May 2nd, took place about seven miles outside the port of Pusan, South Korea. As many as a dozen of the world's several thousand container-carrying vessels are involved in collisions and groundings each year, according to international maritime reports.
"All in all, containers overboard do not pose a serious threat, because few are lost and those seldom float for long," said Thomas McLean, a surveyor in Vancouver. "We do not see ships come in without them much anymore, and those that do are often general cargo ships. They used to stick a bunch of containers on a hatch and chain them down. That just isn't done in this day and age. Face it, if you don't have a strong lashing system, you won't get many customers."
Matson Navigation Company of San Francisco, a leader in the intermodal shipping business, reports that they have not had a container loss in quite a few years. "And even then it was absolutely horrendous weather," said Lynn Korwatch, a licensed operations manager for the company. "Since then we have undergone major changes in our lashing program."
Gary North, director of operations for Matson, added that modern lashing systems have dramatically reduced the incidence of container losses. "With the old wire lashing system we used to have problems," he said, "but new developments have almost made it a thing of the past."
One of Matson's container incidents from the 1980s involved a group of eight refrigerated containers that went overboard near the Columbia River in heavy swell conditions. Most of those containers found their way ashore within 24 hours and broke open on landing, spilling their cargoes of Christmas trees and apples.
The American Bureau of Shipping, responding to this problemwhich has been voiced in many arenashas produced a Guide for Certification of Container Securing Systems. This manual sets out guidelines that every container-carrying ship must meet in order to be properly "classed" by ABS. "Some people probably got together and said, 'Hey, we need uniform requirements for this,'" said Thomas Tucker in ABS's New York regional office. "Everyone is aware that shipping containers are lost in heavy weather, but, at the same time, if it were getting out of hand, I'm sure someone would call it to our attention."
Another recognized intermodal transportation corporation reports that their ships have more problems with containers breaking free on deck than losing them overboard. "When a ship hits a big wave, the water is forced upwards, and it often strikes the bottom of a stack of containers," said the company's manager. "If the framing becomes damaged by the excessive force, the whole stack is in jeopardy. They usually get caught in the spider web of lashings so that our crews have time to go out there and improvise, but every once in a while one will go overboard." He added that most of the losses he has encountered have been off smaller general cargo ships, which may carry up to 50 containers lashed to hatch covers or to the deck.
Everyone agrees that container losses are directly correlated to encounters with storms at sea. The sharp rolling and pitching motions of a ship in a storm can place immense pressures on container lashing systems, especially those of the old wire rope and chain style. Modern containerships make use of rigid, fixed lashing structures as opposed to old-style lash-ups of chain and wire.
Perhaps the most publicized case of container loss in recent history involved the loss of 21 containers, four of which contained toxic materials, off New Jersey during heavy winter weather in 1992.
The Panamanian-flagged Santa Clara I, a break-bulk freighter designed to carry 40-foot containers on its hatches, foundered in heavy weather and lost many containers, some containing the poisonous chemical arsenic trioxide, an insecticide and herbicide. A Coast Guard investigation following the incident determined the cause of the accident to be insufficient lashing methods and poor seamanship.
Coast Guard investigators concluded that Santa Clara I, motivated somewhat by a desire to get offshore before an approaching winter gale, did not set up its lashing system until after it left its loading dock, and then hurried the procedure while underway and using its own crew. The captain later explained to officials that those lashing procedures were standard on his vessel.
Container vessels are less susceptible to these types of losses than break bulk or other general cargo ships by virtue of the fact that they were designed to carry only containers.
"The smaller ships are slower and not really set up to withstand the pressures of rolling with containers," said Terrance Noddle, a surveyor in Jacksonville, Fla. "Modern containerships are large and move at high speeds. Often container-ships have the advantage of being able to avoid the nasty weather."
While some of the containers swept off the decks of the Santa Clara I probably turned up on beaches along the New Jersey coast, most are believed to have sunk. Although nobody hangs around to see what happens after a container is lost, Noddle speculates they do not float for more than a day or two. "A lot depends on the cargo. The empty ones probably float for a while and the heavy ones can sink within a matter of hours. And those loaded with buoyant material like lumber, who knows?" Noddle added that he would be surprised if there were more than four or five instances of container loss in the whole Western Hemisphere in any given year.
Containers vary in size, shape and integrity. Gary North of Matson puts the value of a dry box at $4,000 to $5,000, while refrigerated containers could cost as much as $30,000. A typical container might carry material valued at $50,000 to $1 million or even more, depending on type of cargo. While most containers are airtight, some have vent holes or similar openings.Edit Module