Guided by floating barriers, the Interceptor has already stopped more than 143,000lbs of rubbish from entering the Pacific from one LA river

On an overcast June morning, I step from the rubber-sided Zodiac boat on to a floating barge at the mouth of Ballona Creek, where it meets Santa Monica Bay on the west side of Los Angeles. The first thing I notice? Salty air is the only smell, despite six giant waste bins sitting atop the tennis court-sized barge.

The contraption is actually two barges – a smaller platform sits nestled inside the larger boat. A floating barrier directs rubbish into the device, where a conveyor belt scoops it up. An automated shuttle then distributes the waste into six dumpsters on a separate barge, sending an alert to crews when it is full. Above, solar panels form the ceiling and a conveyor belt runs slowly, dropping bits of plastic and waste into each of the bins. The whole thing can hold about 20,000lbs (9,070kg) of rubbish – the same as one fully loaded lorry.