A massive device created to clean up the world’s oceans is so far failing to pick up plastic.
While the net-like device being dragged through the water is managing to pick up rubbish, it is subsequently dropping it.
The $20m (£16m) project was launched two months ago to tackle the “Great Pacific garbage patch”, which is reported to be twice the size of Texas.
But at the end of November, after a month of attempts, Mr Slat revealed their System 001 device – nicknamed Wilson – was facing difficulties.
“We have observed that plastic is exiting the system once it is collected, so we are currently working on causes and solutions to remedy this,” he wrote.
“Because this is our beta system, and this is the first deployment of any ocean cleanup system, we have been preparing ourselves for surprises.”
While the system was not yet successfully harvesting plastic, Mr Slat said he was confident the team was “close to making it work”, and reported that no interactions with marine life had been observed.
In an update posted this week, the group reported it was still undertaking tests to determine why the problems had arisen.
“This is a challenge we did not predict from our scale models nor prototypes,” they said in a statement.
“Eventually, the only way to truly see how the system would perform was to put it in the environment it has been designed for, and this application has largely been effective.”
While the 600m-long barrier initially picks up the plastic, it appears to be too slow to hold onto it.
The crew will now spend the coming weeks working on a fix, attempting to widen the device so that it is propelled more by wind and waves, and moves faster through the water.
Dozens of scientists and engineers have spent five years testing hundreds of models and prototypes of the current system.
The Ocean Cleanup team estimated that a full deployment of their device could get rid of 50 per cent of the Great Pacific garbage patch every five years.
However, some scientists have expressed concerns about the device, suggesting it is unlikely to make a significant dent in the ocean’s plastic and may in fact cause harm.
Shark biologist Dr David Shiffman was among those who found the project problematic, and polled 15 experts on plastic pollution to establish whether they thought The Ocean Cleanup was a good idea.
He found the majority had major concerns, including flaws in the design, threat to marine life and the amount of money that had been poured into the project instead of other efforts.
There is also a sense among some experts that the project misunderstands the problem of ocean plastic.
While places such as the Pacific garbage patch do accumulate debris, there are far broader problems of global waste management that arguably must be addressed first.
Join our new commenting forum
Join thought-provoking conversations, follow other Independent readers and see their replies