SALEM, Ore. – A large dock that washed ashore in Oregon this week more than a year after it was ripped from Japan's shoreline by a tsunami is adding urgency to preparations for a wave of such debris expected to hit the USA's Pacific Coast in coming months.
"We've got a looming threat. There's great public concern about this," says Phillip Johnson, Oregon Shores Conservation Coalition director. "At this point, we don't know if we're going to have a major problem."
Beach cleanliness is vital to residents in Oregon, the only state whose entire coastline (362 miles) is public. Thousands of people turn out twice a year for beach cleanup events. Others adopt portions of the coastline, cleaning and monitoring them year-round.
So it's no surprise that residents are worried about the tsunami debris that ocean currents could bring ashore, Johnson says.
On Wednesday, Oregon officials confirmed that the dock that washed ashore earlier in the week was from the tsunami. The dock — 7 feet high, 19 feet wide and 66 feet long — is the first official piece of tsunami debris to reach the state.
Japanese officials estimate that 5 million tons of debris washed into the Pacific after the March 11, 2011, earthquake and tsunami, according to the National Oceanic and Atmospheric Administration (NOAA). About 70% of that sank, leaving about 1.5 million tons floating.
Most of the debris still is north of Hawaii, says Nir Barnea, West Coast regional coordinator for NOAA's Marine Debris Program.
Scientists expect more debris to hit the West Coast in coming months and through 2014.
"It will arrive intermittently and not all at one time and place," Barnea says. "It may be difficult to tell what is tsunami-related and what is not. Even floats with Japanese writing are not necessarily from the tsunami."
While scientists expect much of the floating debris to follow the currents to the Great Pacific Garbage Patch, an accumulation of millions of tons of small bits of plastic floating in the northern Pacific, tsunami debris that can catch the wind is making its way to North America. In recent weeks a soccer ball washed up in Alaska, and a Harley Davidson motorcycle in a shipping container in British Columbia.
Just how the dock float happened to turn up in Oregon was probably determined within sight of land in Japan, says Jan Hafner, a computer programmer in the University of Hawaii's International Pacific Research Center, which is tracking the debris.
That's where the winds, currents and tides are most variable, due to changes in the coastline and the features of the land, even for two objects a few yards apart, he says. Once the dock float got into the ocean, it was pushed steadily by the prevailing westerly winds and the North Pacific Current.
In April, a group of volunteer organizations teamed with NOAA and state officials to hold 11 public meetings across Oregon to address concerns about tsunami debris. About 400 people attended, says Jamie Doyle, an educator with Oregon Sea Grant.
"A lot of people were concerned about radiation," Doyle says, referring to the nuclear power plant accident in Japan that was triggered by the earthquake and tsunami. "But it's thought to be highly unlikely."
That's because most of the debris was washed out before the radiation release, and because radiation would have dissipated and dispersed by now, Barnea says.
Body parts also are not expected, because they would have decomposed by now, he says.
The most important message, Barnea says: "If you don't know what it is, don't touch it. Don't move it. Report it to local authorities, 911, or the national response center."
A mobile application at marinedebris.engr.uga.edu helps people report coastal debris. It is a joint partnership of the NOAA Marine Debris Division and the Southeast Atlantic Marine Debris Initiative of the engineering school at the University of Georgia.
In addition to Oregon, other West Coast states are educating residents about tsunami debris cleanup, Barnea says.
•In Alaska, some lighter debris, such as plastic bottles and Styrofoam floats, already is showing up. The first volunteer cleanup project in the state took place in Montague Island this month.
•In Washington, authorities have distributed fliers with instructions on how to handle items found on beaches.
•In California, officials think currents along the coast may deflect most of the debris back toward Hawaii. Still, the California Coastal Commission has issued guidelines for volunteers helping with tsunami debris removal.
"We'll continue to work on the planning, continue to work with volunteers," Barnea says. "It's a real teamwork of state, federal and local agencies, non-governmental organizations, and the public."
Agate Beach
 Rund 15 Monate nach dem verheerenden Erdbeben und Tsunami im Osten Japans ist an der US-Westküste das bisher größe Trümmerstück angespült worden. Wie Mitarbeiter des japanische Konsulats in Portland, Oregon, anhand von Aufschriften bestätigten, handelt es sich bei dem in Agate Beach gestrandeten, rund zwanzig Meter langen Teil aus Styropor, Metall und Beton um Teile eines Schwimmdocks.

Es wird davon ausgegangen, dass rund fünf bis 20 Millionen Tonnen Trümmer nach dem großen Erdbeben mit der Magnitude 9 Mw auf der Momenten-Magnituden-Skala von der Flutwelle mitgerissen und auf den offenen Pazifischen Ozean gespült wurden. Diese behindern nun die Schifffahrt, Gefahr droht aber auch der Umwelt. Im April hatte die Küstenwache der Vereinigten Staaten vor der Küste im Südosten des Bundesstaates Alaska ein treibendes japanisches Wrack versenkt.