The city of Baltimore has installed a solar-powered water wheel that can process 23 metric tonnes of floating garbage every day.
Image: Andrew David Thaler
There’s no way to know for sure, but scientists estimate the amount of plastic bobbing around the world’s oceans is around 1 million tonnes - and that’s a conservative estimate. And to make matters worse, much of this waste is accumulating in five large floating islands of garbage, two in the Atlantic Ocean, two in the Pacific Ocean, and one in the Indian Ocean.
Obviously there’s a problem, but a little solar-powered water wheel has emerged as the most promising new technology to start cleaning up this mess.
The water wheel was installed last May in Baltimore’s Inner Harbour in the US, situated at the mouth of where one of its major rivers flow into the harbour. According to Svati Kirsten Narula at Quartz, the wheel works by lifting rubbish and debris out of the harbour water using a 'debris raking system', which transfers the collected items onto a conveyer belt and then into a dumpster barge. The conveyer belt is powered by the harbour's water.
Between May 16 and June 16, the wheel processed 46 metric tonnes of rubbish in Baltimore’s harbour - rubbish that would have ended up in Chesapeake Bay and eventually the Atlantic Ocean had it not been intercepted. If placed in waters where the rubbish density is much higher, it could process up to 23 tonnes every day.
The best thing about this little machine is that it’s getting experts excited about its potential.
"Creative solutions [to ocean rubbish] abound, but few strike marine conservation experts as practical or praise-worthy. Too often, says ecologist Andrew David Thaler, projects like floating plastic-filter machines amount to little more than 'concept art’," says Narula at Quartz.
Thaler, a marine science PhD and the editor of Southern Fried Science, told Narula that this is the first “truly feasible” contraption to reduce ocean plastic.
Watch it work after a recent rain storm: