The March 2011 earthquake/tsunami that ravaged the coast of central Japan is most notorious for killing 19,000 people and triggering a radioactive meltdown. Surging as far as 6 miles (10 kilometers) inland and flooding around 217 square miles (561 square kilometers), the tsunami also splintered thousands of fishing boats, knocked out houses and sucked away anything that wasn’t bolted to the ground.

Where did that 5 million tons (4.5 tonnes) of debris go? Some of it formed a pile of debris the size of Texas. Just as that state once annexed itself to the US, this floating Texas-sized trash heap is about to join borders with the American West Coast. Nearly 32 months after the tsunami hit, it’s now around 1,700 miles off the Pacific coast, according to the National Oceanic and Atmospheric Administration (NOAA):

National Oceanic and Atmospheric Administration ​

There have already been signs of the trash island’s approach. So far, a 185-ton dock washed up in Washington, and a rust-caked “ghost ship” (meaning a derelict fishing boat) met the coast of British Columbia. There have been reports of even the smallest found items that trace back to Japan, such as a Japanese boy’s soccer ball and then a volleyball found by a beachcomber in Alaska. Here’s where debris has shown up so far:

National Oceanic and Atmospheric Administration ​

Tests performed on those early arrivals have helped assuage what’s probably the most obvious fear—that the debris will be contaminated:

A subtler but more menacing threat is the arrival of Japanese invasive species, which could skew ecological balance on the West Coast. John Chapman, an Oregon State University marine biologist, told Fox.com that his center has already found 165 alien species on floating debris so far on the West Coast. Creatures like the European blue mussel—itself introduce to Asia long ago from Europe—could imperil native species. Chapman and other scientists had doubted that the creatures could travel the long distance across the Pacific. Here are a few that made the trip on that floating dock that washed up in Washington, via OSU’s marine debris blog: