Authors: Hannah Horsfield & Julie Steele, Bermuda Underwater Exploration Institute
In a continuing series on marine debris to mark World Oceans Day on Tuesday, Bermuda Marine Debris Taskforce members Hannah Horsfield and Julie Cross Steele look at methods of skimming trash off the surface of oceans, inland waters and harbours.
As marine plastic accumulates in the ocean at an alarming rate, the need for efficient and sustainable remediation is urgent. It is estimated that there are 5.25 trillion pieces of plastic in our ocean with approximately 8.3 million tonnes entering the seas each year. A combination of sustainable technologies and adopting preventive behaviours is our best chance of ensuring that there will always be more fish than plastic in the ocean.
Organisations such as the Ocean Cleanup are deploying large-scale technologies to address the massive plastic gyres and to intercept plastic at the mouth of major rivers and waterways.
An example of a smaller scale interceptor can be seen in Baltimore. “Mr Trash Wheel” catches riverine trash before it has a chance to reach the ocean. A floating boom diverts the trash on the river towards the cute and cleverly covered barge. River currents and solar panels power a water wheel which drives the conveyor belt, depositing the trash into floating replaceable dumpsters. In the seven years of operation, trash wheels in Baltimore have collected more than one million polysterene containers and plastic bottles and more than 12 million cigarette butts.