Plastics can be retained in river systems for years and even centuries, but compared to marine debris, the amount of plastic pollution in rivers has been poorly quantified. There’s a reported lack of consistent and long-term observations of plastics in freshwater settings. Plus, the movement of plastics in waterways can be very dynamic and varied, and gathering reliable data about abundance and transport is crucial to supporting pollution prevention. At the European Geosciences Union’s (EGU) General Assembly this year, a team of international scientists showed how remote sensing could be used to monitor plastic pollution in aquatic settings. They identified plastic-laden hyacinths in satellite imagery from the European Space Agency to quantify the amount of plastic pollution in the Saigon River near Ho Chi Minh City, Vietnam.