The Ocean Cleanup's System 001, a giant machine known as “Wilson” out at sea cleaning up plastic pollution, has returned to port for repair after less than three months out in the Pacific Ocean.

Officials announced on Ocean Cleanup’s blog that on Dec. 29, 2018, during a regular inspection of the cleanup system, an offshore crew discovered that an 18-meter end-section had detached from the rest of the system. They speculated that material fatigue and stress concentration caused a fracture, though they cautioned that the exact cause is unknown.

No material was lost, and both the 580-meter main section and the 18-meter end section are completely stable with all bulkheads intact. The blog post also says there were no safety risks for the crew, environment or passing marine traffic.

Wilson launched from the San Francisco Bay on Sept. 8 and reached the Great Pacific Garbage Patch, an area containing litter nearly twice the size of Texas off the coast of California, Oct. 16, 2018.

Wilson consists of a 600-meter-long U-shaped floater that sits at the surface of the water and a tapered 3-meter-deep skirt attached below. The floater provides buoyancy to the system and prevents plastic from flowing over it, while the skirt stops debris from escaping underneath. The system is designed to capture plastics ranging from small pieces up to large debris, including massive discarded fishing nets, which can be tens of meters wide. Ocean Cleanup says that a full-scale cleanup system roll-out (a fleet of approximately 60 systems) could clean 50 percent of the Great Pacific Garbage Patch in five years.

However, the breach in equipment brought Wilson inland sooner than expected.

“We are, of course, quite bummed about this as 1) we hoped to stay out for a bit longer to collect more data on plastic-system interaction, and 2) it introduces an additional challenge to be solved,” Ocean Cleanup Founder and CEO Boyan Slat wrote on the blog post. “At the same time, we also realize that setbacks like this are inevitable when pioneering new technology at a rapid pace. Being in port provides us with the opportunity to make upgrades to the system with the aim of solving the plastic retention issue, which we previously reported.

“… Although we would have liked to end the year on a more positive note, we believe these teething troubles are solvable, and the cleanup of the Great Pacific Garbage Patch will be operational in 2019,” Slat continues. “The fact that the cleanup system orients itself in the wind, is able to follow the waves well and is able to catch and concentrate plastic gives us confidence in the technology.”

Slat says Wilson will be back out to sea when the weather is conducive to sailing.