The devastating tsunami that struck Japan last spring did more than cause localized death and destruction; it also swept up to 25 million tons of debris out to sea. That debris—including houses, gas stations, cars, and boats—is now floating around in the ocean. But where it will end up and how we will dispose of it is still up for debate.
There are some clues. This past September, the Russian research vessel STS Pallada (PDF) encountered the wrecks of small fishing vessels from the disaster while traveling from Honolulu back to Russia. One of the crew members wrote: "We also sighted a TV set, fridge, and a couple of other home appliances. … We keep sighting everyday things like wooden boards, plastic bottles, buoys from fishing nets (small and big ones), an object resembling wash basin, drums, boots, other wastes."
The crew tested the fishing vessels for radioactivity and found none—good news for anyone worried about massive amounts of radioactive material washing ashore. But based on where the items were found, scientists believe that debris could wash up on the Hawaiian islands as early as this winter.
"According to modeling and minimal observations, the debris is currently kind of sitting off the northwest territory of the Hawaiian islands," explains Mary T. Crowley, the founder of Project Kaisei—which studies the Great Pacific Garbage Patch—and president of the Ocean Voyages Institute. "Because it’s an important marine sanctuary area with lots of reef and ocean habitat, we hope that it will not land there." Crowley believes that the debris could be headed to Oregon, Washington, and British Columbia next.
But Dianna Parker, a spokeswoman for the National Oceanic and Atmospheric Administration (NOAA), cautions that we can’t be too sure of anything: "It’s entirely possible that most of the debris will get caught up in the Pacific garbage patches. The models that we have don’t account for the fact that items sink, break up, and scatter. It’s a matter of what types of things make it across the Pacific and onto land."
Nevertheless, Crowley is working with naval architects and marine scientists to figure out the best way to clean up large items—something that Project Kaisei has long been working on for smaller pieces of ocean debris. "With large, unusual objects like houses, trees, refrigerators, that naturally takes a bit of a different approach," says Crowley.
It’s hard to say exactly at this point how large pieces of tsunami debris can be cleaned up, but Crowley speculates that barges, cranes, and excavators—"ocean construction kind of equipment," she says—will be used (Low Tech Magazine looks at a variety of marine debris-collecting vessels here).
The Rozalia Project, meanwhile, is already at work removing ocean debris with a combination of nets, remotely operated underwater robots (they come equipped with a manipulator to grab trash), and sonar. But without giant robot manipulators and huge, ultra-strong nets, this won’t be enough to gather up at least some of the tsunami debris.
And what can be done with the trash once it’s recovered? Dutch architect Ramon Knoester has one idea: a 10,000 square kilometer recycled island made out of plastic from the Pacific Garbage Patch. Researchers from the Clean Oceans Project want to turn that same plastic into fuel. Not all of the tsunami debris is plastic by a long shot, but at least some of it can be reused, barring any unexpected radioactivity.
There are so many unknowns in the Japanese tsunami debris situation that it’s hard to say how we’ll need to handle it. But chances are, it won’t be anything too dramatic—giant debris fields won’t clog ports and create havoc. Instead, more and more trash will likely pile up in the ocean, which is increasingly becoming a garbage dump for oil, plastic, and other debris. And if debris from the tsunami does wash up en masse, who will deal with the remnants of a Japanese gas station on the beach? "The big question is, who is going to step up to help pay for all this?" wonders Crowley.