State workers removed a boat, apparently sent on a long journey by the 2011 Japanese tsunami, from Alan Davis Beach on the Ka Iwi shoreline Thursday.

The 20-foot skiff, bearing Japanese characters and vessel registration numbers, washed up earlier in the week at the beach between Sandy Beach Park and the Makapuu Lighthouse trail.

The state Department of Land and Natural Resources said two large blue plastic bins, which bore identification marks that may be traceable to Japan, were also reported this week.

Hawaii Wildlife Fund volunteers removed one bin from Kamilo Beach on Hawaii island. Another bin was found on Kauai at Larsen’s Beach.

Items with identification numbers or Japanese characters are reported to the National Oceanic and Atmospheric Administration, which works with the Japanese Consulate in Hawaii to try to locate the original owner. If the items aren’t claimed, they are disposed of.

A tsunami generated by a magnitude-9 earthquake on March 11, 2011, off Japan’s northeastern coast left more than 18,000 people dead or missing.

The Japanese government estimated that the tsunami swept about 5 million tons of debris into the ocean and that about 70 percent sank quickly.

The remaining debris dispersed across the North Pacific, scientists said.

The boat was the seventh reported in Hawaii since February. Three were on Hawaii island, at Kohanaiki, Kawaihae and Kawa Bay; one was recovered on Maui near the Aston Mahana; and two on Oahu were reported at Kahuku and Punaluu.

Scientists predict tsunami debris will continue to arrive for at least the next three years.

NOAA said items confirmed to have come from the Japan tsunami include vessels, buoys, sports balls, floating piers and a motorcycle in a shipping container. Other types of debris that could wash up include fishing nets, lumber, plastics, household items, foam pieces, and possibly chemical or oil drums.

Scientists said wind and currents are the two major factors influencing the drift of the tsunami debris. Large debris with exposure to the wind tends to wind up on the West Coast.

In 2013, Hawaii and four other western states affected by debris from the 2011 tsunami received $250,000 each from a $5 million gift from Japan for cleanup.

Report large or unusual marine debris, especially objects that may have attached marine organisms, to dlnr.marine.debris@hawaii.gov and disasterdebris@noaa.gov. Calls may also be made to DLNR at 587-0400.