Since the beginning of July, a 300-foot barge has snaked down North America’s West Coast, starting in Alaska and slowly making its way to Seattle.

Its cargo: trash. Lots of it.

The month-long barge operation is part of a massive project to clean remote and rugged shorelines of tons of marine debris, some of it from the 2011 Japanese tsunami. Helicopters are slinging giant sacks of debris out to the floating barge, which is expected to arrive in Seattle this week. Some of the material will be recycled there; the rest will be taken farther south to an Oregon landfill.

Local, state and international governments and nonprofits are involved in the effort. It is being funded in large part by the Japanese government, which is paying $6 million to United States and Canada for the cleanup.

In 2011, a 9.0-magnitude earthquake more than 200 miles from Tokyo set off 30-foot waves and a tsunami that killed more than 15,000 people, caused $300 billion in damage and swept about five million tons of debris into the ocean. While the Japanese government estimated 70 percent of that quickly sank to the ocean floor, the remaining floating debris is widely dispersed, according to the National Oceanic and Atmospheric Administration.

Some of that debris has been massive: In 2012, a 200-ton dock landed on Agate Beach in Oregon, where it remained for months before workers broke it apart. Earlier this year, a boat with 20 fish usually found in Japanese waters showed up off the central coast of Oregon.

By the time the barge got to the fishing town of Ucluelet in British Columbia on Tuesday, it was carrying 3,334 “super sacks” of debris. Each of those sacks can hold up to 1,000 pounds, said Ucluelet’s environmental and emergency services manager Karla Robinson.

Since the tsunami, volunteer pickups in Ucluelet, including those involving local and Japanese students, have yielded pieces of Japanese houses, Styrofoam and other debris. There’s also a lot of the debris on the shore not from the tsunami, Robinson said.

“We’ll clean up a beach one year and go back and it’ll be full again,” she said. “There’s layers of this material. Once you get through one layer, there’s another layer interwoven into the vegetation.”

For places like Ucluelet, such cleanups can be a challenge. “The coastline is very remote, rugged and hard to access,” Robinson said. And, she said, it’s even harder to get “this cumbersome material” onto boats.

The helicopter slings help. Robinson said nonprofit groups, volunteers and others participated in a cleanup effort to get the sacks onto the shore, ready for pickup. She emphasized the collaborative nature of the barge project and the growing problem of marine debris.

“It’s a drop in the bucket to how much material is out there,” she said.

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