In recent years, heart-rending images of dead or dying sea mammals and fish, their stomachs stuffed with plastic, have shocked citizens around the globe. Reports indicate that the amount of plastic dumped into the world’s oceans has tripled over the past decade. And unlike oil spills, which can be remedied with extensive and costly clean-up efforts, there is no obvious solution to plastic “spills.” But a growing number of countries, some backed by the World Bank, are turning to drones to aid their efforts.
Tanzania, for example, is combining ground clean-ups of its beaches and coastlines with aerial video surveillance by drones that can help identify concentrations of plastic for collection. Funded through the World Bank’s PROBLUE program, the project is being coordinated by Dr. Blandina Robert Lugendo at the University of Dar es Salaam UDSM in conjunction with Tanzania FlyingLabs, a drone and technology lab. The surveillance and collection effort focuses on 11 coastal “hotspots”— eight on Tanzania’s mainland coast and three in neighboring Zanzibar.
Project organizers say the effort is aimed at protecting not only the area’s lucrative tourism industry but also its threatened fisheries. Tanzania depends on both industries to sustain its development. So far, drone surveillance has helped Lugendo’s team put together a comprehensive map of plastic pollution, identifying different types of waste and their respective concentrations. It also improved her team’s strategic planning and helped make its field collection more precise. Finally, aerial drones have facilitated the tracking and evaluation of the project’s progress over time.
Similar benefits are being realized thousands of miles away in Denmark where a local government has deployed a combination of aerial and marine drones to aid in the clean-up of inland waterways. In this case, drones are actually collecting garbage and litter, especially plastics, left behind by careless tourists and residents. Aerial drones identify the trash concentrations and dispatch signals to marine drones that automatically deploy to the hot spot to conduct the collection. The aerial drones can even detect oil slicks, as well as litter, and some of the marine drones are equipped with devices that also allow them to remove petroleum from the water. The marine drones, which sail continuously on the water’s surface, can collect a prodigious amount of garbage – about 1,100 pounds, daily.
The city of Aarhus first began its garbage collection project in July 2019 with a single sailing drone – the custom-built WasteShark – deployed near the mouth of the Aarhus River. Last year, with support from the national government, Aarhus purchased a DJI Mavic drone to create its combined aerial-marine collection system. The city said it chose the DJI Mavic for its cost and commercial availability in the hopes of modeling an unmanned trash collection system that other cities could easily replicate.