A large dock that floated onto an Oregon beach is debris from last year's tsunami in Japan, Japan's consulate in Portland said Wednesday.

The 66-foot-long dock, which had been in use in an area hit by the March 2011 tsunami, is the largest piece of debris discovered on North America's shores so far. 

"It’s one of four floating docks washed away by the tsunami, which means there are three more floating somewhere possibly," OregonLive.com quoted Deputy Consul General Hirofumi Murabayashi as saying.

A check for any radiation from Japan's Fukushima nuclear plant came up negative, said Oregon Department of Parks and Recreation spokesman Chris Havel.

The department  is overseeing efforts to remove the dock but hasn't decided yet whether to demolish it on site or have it towed off. "You can't preplan for stuff like this," Havel told msnbc.com.

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A starfish native to Japan was found clutching to the structure, Havel said, adding that another concern is to keep out any nonnative species that might have hitched a ride on the dock.

The dock, which is 19 feet wide and 7 feet high, washed ashore Tuesday on Agate Beach, a mile north of Newport in central Oregon.

Small groups had already gathered to see the dock and state police were posted to keep people from climbing on it. 

"I think that's going to change to large crowds," Havel said.

Some tsunami debris has begun arriving in recent weeks, including a soccer ball that washed up in Alaska and a shipping container holding a Harley-Davidson motorcycle with Japanese license plates that turned up in British Columbia. 

Most debris is not expected until winter.

Anyone finding debris thought to be from the tsunami is advised to report it to DisasterDebris@noaa.gov. 

The Associated Press contributed to this report.

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A Japanese man’s Harley-Davidson motorcycle that washed up on the shores of western Canada more than a year after it was swept away by the devastating tsunami will be preserved in a Harley museum in the U.S.

The 2004 FXSTB Softail Night Train motorcycle will be permanently housed in the Harley-Davidson Museum in Milwaukee, Wis., as a memorial to the victims of the March 2011 earthquake and tsunami, which swamped several coastal towns in northeastern Japan and left more than 15,000 people dead.

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“It is truly amazing that my Harley-Davidson motorcycle was recovered in Canada after drifting for more than a year,” said the bike’s owner, Ikuo Yokoyama, in a press release issued Friday by Deeley Harley-Davidson, the Canadian distributor of Harleys. “I would like to take this opportunity to express my heartfelt appreciation to Peter Mark, the finder of my motorcycle. Due to circumstances caused by the disaster, I have been so far unable to visit him in Canada to convey my gratitude.”

Mark found the motorcycle, still bearing its Japanese license plate, while driving his ATV on an isolated beach on Graham Island on the west coast of British Columbia on April 18. The bike, along with several other items, was inside a rusted cargo van container that apparently drifted more than 4,000 miles across the Pacific Ocean.

“You just never know what you’re going to stumble upon when you go for a drive, and lo and behold you just come across something that’s out of this world,” Mark told CBC at the time.

The motorcycle was eventually traced to the 29-year-old Yokoyama.

The tsunami destroyed Yokoyama’s home in Miyagi prefecture and also claimed the lives of three family members, according to Japanese media reports. Yokoyama currently lives in temporary housing in Miyagi prefecture.

He said the motorcycle was being kept in a storage container behind his house when the tsunami struck.

Harley-Davidson offered to return the rust-encrusted bike to him and to restore it to running condition but Yokoyama respectfully declined, the company said.

“Since the motorcycle was recovered, I have discussed with many people about what to do with it. I would be delighted if it could be preserved in its current condition and exhibited to the many visitors to the Harley Davidson Museum as a memorial to a tragedy that claimed thousands of lives,” Yokoyama was quoted as saying in Friday’s press release.

Harley-Davidson has offered to fly him to visit the museum and meet Marks, the Canadian who retrieved the bike. Yokoyama said he would like to do so “when things have calmed down.”

“My heart really goes out to Ikuo Yokoyama and all the survivors of the Tohoku earthquake and tsunami for everything that was taken from them. I cannot even begin to comprehend the loss of family, friends, and community,” Mark was quoted by Harley-Davidson as saying. “I think it is fitting that the Harley, which was swept across the Pacific Ocean by the tsunami, will end up in the Harley-Davidson Museum as a memorial to that tragic event. It has an interesting and powerful story to convey preserved in its current state.”

The motorcycle has since been transferred to a Harley dealership in Vancouver. Plans for its transportation to the Harley museum are being developed.

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ANCHORAGE, Alaska -- Cleanup workers will on Friday attack a jumble of debris from Japan's 2011 tsunami that litters an Alaskan island, as residents in the state gear up to scour their shores for everything from buoys to building material that has floated across the Pacific.

The cleansing project slated to start on Montague Island is expected to last a couple weeks, and organizers say it marks the first major project in Alaska to collect and dispose of debris from the tsunami.

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The March 2011 tsunami, caused by a magnitude 9.0 earthquake, killed nearly 16,000 people and left over 3,000 missing on Japan's main island of Honshu, and precipitated a major radiation release at the Fukushima Daiichi nuclear plant.

A U.S. senator has sought to obtain $45 million to tackle the problem, and officials have cited fears about invasive species and toxic substances thought to be among the floating mess of objects.

Harley-Davidson washes up on Canadian coast

While debris from Japan is also floating toward other U.S. states along the West Coast, Alaska has a more extensive shoreline, much of it difficult to reach.

'Just a start'
Montague is an uninhabited island at the entrance to Prince William Sound, southeast of Anchorage. About a dozen volunteers and employees from the environmental group Gulf of Alaska Keeper and the Center for Alaskan Coastal Studies will handle the debris-removal project at the island.

"We'll probably remove 30 to 40 tons from there. That's just a start," said Patrick Chandler, special programs coordinator for the Center for Alaskan Coastal Studies.

Japan has estimated 5 million tons of debris was swept out to sea, but that most of it sank, leaving 1.5 million tons floating. Still, those figures are rough estimates, said the National Oceanic and Atmospheric Administration.

Observers flying over the Alaska coast have spotted, among other items, huge numbers of barrel-sized polystyrene foam buoys, often associated with Japanese oyster farms.

Tiny specks of polystyrene foam that break away from larger objects can be dangerous to seabirds or marine mammals, because they resemble eggs or other food morsels, Chandler said.

Japanese teen traced as owner of soccer ball found in Alaska

Another worry is that floating debris might carry invasive species, such as barnacles, that would wreak havoc in waters off Alaska and the U.S. West Coast, said Doug Helton, the Seattle-based coordinator of NOAA's office of response and restoration.

Then there is the danger from noxious substances in partly full fuel jugs, cleanup organizers said.

Last month, the U.S. Coast Guard sank a 164-foot fishing boat from the Japan tsunami that drifted near Alaska. The Coast Guard said the so-called "ghost ship" was a navigational hazard.

With more debris headed for the West Coast, questions about cleanup costs remain unanswered. Those expenses could be high in Alaska because of geographic and weather challenges.

U.S. Senator Mark Begich of Alaska suggested last week that NOAA provide $45 million as an initial outlay to fund what is expected to be a sustained and difficult beach cleanup.

Meanwhile, David Baxter, a technician who works at a Federal Aviation Administration station on the uninhabited Middleton Island in the Gulf of Alaska, has made some notable finds on his rounds in his hobby of beachcombing.

Earlier this month, the owner of a tsunami-wrecked restaurant in the coastal Miyagi Prefecture spotted one of her buoys among Baxter's debris photos posted online. The yellow buoy was part of the restaurant's sign, he said.

Baxter has arranged to send it back to the woman. "Now that her buoy's found, she's going to rebuild," he said.

On Wednesday, the World Health Organization said increases in radiation linked to the Fukushima disaster were below cancer-causing levels in nearly all of Japan.

The agency's 124-page report also says neighboring countries had levels similar to normal background radiation and for the rest of the world there was some minor exposure through food.

The U.N.'s International Atomic Energy Agency had previously confirmed that radiation levels in some Japanese milk and vegetables reached significantly higher levels than Japan allows for consumption.

Reuters and The Associated Press contributed to this report.

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A volleyball and soccer ball that washed ashore on an Alaskan island may be the first pieces of debris to arrive in the United States from last year's tsunami in Japan.

The sports balls were spotted by radar technician David Baxter on treeless, windswept Middleton Island in the Gulf of Alaska, Doug Helton of the National Oceanic and Atmospheric Administration in Seattle said in an agency blog post.

Baxter’s wife translated writing on the soccer ball and traced it back to a Japanese school in an area hit by the tsunami, Helton said.

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He told the Anchorage Daily News the balls were the first tsunami debris retrieved in Alaska.

 

"There have been other items that were suspected, but this is the first one that we're aware of that has the credentials that may make it possible to positively identify it."

Helton, in the NOAA post, said the agency, the State Department and the Japanese Embassy and its Seattle consulate are working to confirm details and set up the return of other debris that comes ashore.

A magnitude 9.0 earthquake off Japan's northeast coast on March 11, 2011, triggered a 75-foot wall of water that flattened waterfront towns, killing 16,000. Three thousand people are still unaccounted for. The tsunami triggered a crisis at Tokyo Electric Power's Fukushima Daiichi atomic power plant, forcing tens of thousands of people to flee in the world's worst nuclear accident in 25 years.

U.S. authorities were immediately aware that the clockwise circulation of the Pacific's northern waters would deliver some remnants of that destruction to American shores.

A Japanese ghost ship Ryou-Un Maru turned up earlier in the Gulf of Alaska off Southeast Alaska after a 4,500-mile journey. The U.S. Coast Guard ended sank the vessel April 5.

In January, a half-dozen large buoys suspected to be from Japanese oyster farms appeared at the top of Alaska's panhandle and may be among the first tsunami debris.

State health and environmental officials have said there's little need to be worried that debris landing on Alaska shores will be contaminated by radiation.

This article contains reporting by Reuters and The Associated Press.

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A massive earthquake like the one that unleashed a giant tsunami and killed nearly 16,000 people in Japan a year ago not only could happen here in the U.S., but probably will — and relatively soon in terms of seismological history.

The Tohoku earthquake was the most closely monitored in history, yielding an unprecedented breadth of data, geophysicists and seismologists say. And for residents of the Pacific Northwest, the new data should be worrisome.

"It's just like Japan, only a mirror image," said Gerard Fryer, a geophysicist at the University of Hawaii and the Pacific Tsunami Warning Center.

The disaster in Japan occurred because of stress from the Pacific tectonic plate sliding below Japan, according to new research discussed last month at the annual conference of the American Association for the Advancement of Science in Vancouver, British Columbia.

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The lead researcher, John Anderson, a geophysicist at the University of Nevada-Reno, said the plates locked together, slowly pushing Japan westward.

The plates released catastrophically on March 11, 2011, creating a magnitude-9.0 earthquake and tsunami waves that topped 100 feet, said Anderson, who spent most of the past year in Japan as a visiting research professor in Tokyo.

While most Americans probably think the San Andreas fault running through California poses the greatest threat of unleashing a killer mega-quake, data from the Japanese quake indicate that the distinction actually belongs to the Cascadia fault line, which runs through southern Canada, Washington and Oregon to Northern California, Anderson said at the conference.

USGS earthquake information by state

Like Fryer, he called the Pacific Northwest trench a "mirror image" of the Japanese trench — except potentially even more dangerous.

"In this mirror image, one can see that if the same earthquake occurred in Cascadia, the fault would rupture to a significant distance inland, since the Cascadia trench sits much closer to the coastline than the trench off the coast of Japan," Anderson said.

While some probability models predict that a Cascadia earthquake wouldn't rupture so far under the land, "if it does, the data from the Tohoku earthquake predict stronger ground motions along our West Coast than those seen in Japan," he said.

In layman's terms, what's happening is that the region "is being deformed because the plates are locked together, and the shoreline is sinking and the rest of the thing is being bent," Fryer said in an interview with NBC station KHNL of Honolulu.

Fryer said the big question is not whether a Japan-like quake will happen, but when.

"Where are we here? Are we close or are we not close?" he asked. "I think the suspicion is that it could be sooner rather than later."

Anderson's research supports that conclusion.

Experts generally agree that last great Cascadia earthquake happened on Jan. 26, 1700. It generated tsunami waves that indicated that its magnitude was also about 9.0.

"Earthquakes of this size in the past may have recurred with intervals of as small as about 300 years," Anderson said at the AAAS conference last month. "So it would not be a scientific surprise if such an event were to occur in the near future. If you live in the Pacific Northwest, look at the videos of Tohoku as a reminder to be prepared."

The warnings come as the White House is proposing a 2013 budget that would cut $4.6 million from National Oceanic and Atmospheric Administration's tsunami programs. Much of that would come from the National Tsunami Hazard Mitigation Program, which funds evacuation maps, training and education efforts — important services given how deeply the Japanese quake and tsunami transformed the science of seismology.

"The Japan earthquake told us that a lot of what we understand about how earthquakes work is wrong," Fryer said. "Do we now have to go back and look at all of our evacuation maps and make sure that they're right? That's a question that's still unanswered, and that question would be answered with tsunami hazard mitigation program funds."

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