More than a year after a tsunami struck Japan's east coast, California beachcombers are preparing for a wave of debris expected to hit the U.S. Pacific Coast in coming months.
"It's going to be a growing issue over the coming year as more debris starts to arrive in California," says Eben Schwartz, California Coastal Commission outreach manager. "It will be a good opportunity to educate Californians about the ongoing marine debris problem."
Next Saturday, as tens of thousands of volunteers participate in California's 28th annual Coastal Cleanup Day, identifying potential tsunami debris on beaches will be part of the undertaking.
"We hope to be able to identify trends ... that could help us firmly establish when, or if, the debris form the tsunami is starting to arrive in bulk along our shores," Schwartz says. "At the same time, we don't want to lose sight of the fact that the California coast is polluted by thousands of tons of debris every single year, no matter what natural disasters may or may not have occurred."
The Japanese government estimates that 5 million tons of debris washed into the Pacific Ocean after the March 11, 2011 tsunami, according to the National Oceanic and Atmospheric Administration. An estimated 70 percent of that sank, leaving 1.5 million tons floating. There is no estimate of how much is still floating after being at sea for more than a year.
Some debris has already arrived. A large dock ripped from Japan's shoreline washed ashore in Oregon in June. Other items recovered north of the California border include vessels, a buoy, sports balls and a motorcycle.
Fishing nets, lumber, plastics, household items, foam pieces and possibly chemical or oil drums are other things from Japan expected to make landfall anywhere from Alaska down to California and Hawaii, scientists say.
So far, radiation experts agree it is highly unlikely any of the debris will hold harmful levels of radiation from the Fukushima nuclear emergency. Ocean trash off Hawaii's shores has been monitored for more than year, and no abnormal radiation levels have been found.
"The reactors didn't melt down until days after the wave hit, and the wave hit a wide area," Schwartz says. "That said, there is the potential of other dangerous stuff."
Ocean trash is pushed by wind and currents, and predicting accurately where it will go can be difficult. But U.S. officials say beachgoers may notice a gradual increase in debris on beaches over many years, in addition to marine debris that normally washes up.
"The most important thing for us to do at the moment is to capture the increased volunteer momentum around marine debris that we are seeing right now," Schwartz says. "We want to be able to direct those volunteers to cleanup events where they can be safely overseen and put to work by our trained volunteer organizers while helping rid our coast of debris, no matter where it might have originated."