The European project MAELSTROM has officially concluded: more than 4 tonnes of marine litter have been removed, innovative technologies developed, and local communities actively engaged through an integrated approach to tackle plastic pollution. Awarded the Blue Rivers & Lakes Award for innovation, the project leaves a legacy poised to become a reference model across Europe.
Every year, millions of tonnes of plastic enter our seas, disrupting ecosystems, threatening biodiversity, and endangering human health. Yet, the fight against marine litter does not begin on the beach or seabed. It starts much earlier—along rivers, in cities, and through everyday consumer choices. That is why MAELSTROM stands as a concrete example of how science, technology and international cooperation can act as catalysts for transformation. This European initiative went beyond removing plastic from the sea—it aimed to reshape our relationship with waste, turning it into a source of value, knowledge and change.
That is why, in celebrating the International Day of Zero Waste, we look at the MAELSTROM project as a concrete example of how science, technology and international cooperation can act as catalysts for transformation. This European initiative went beyond removing plastic from the sea—it aimed to reshape our relationship with waste, turning it into a source of value, knowledge and change.
A stream of innovation: MAELSTROM between technology and sustainability
Funded by the European Commission under the Horizon 2020 programme, MAELSTROM—Smart technology for MArinE Litter SusTainable RemOval and Management—brought together 14 partners from 8 European countries to reduce the impact of marine litter in both coastal and riverine environments. Coordinated by the Institute of Marine Sciences of the Italian National Research Council (CNR-ISMAR), the project followed an integrated trajectory combining environmental modelling, advanced robotics, artificial intelligence, and circular economy principles.
The technologies developed and tested represented a breakthrough: on one side, the Bubble Barrier deployed on the Ave River in Vila do Conde (Portugal), designed to intercept floating and sub-surface litter before it reaches the ocean, powered by solar energy; on the other, the Robotic Seabed Cleaning Platform, successfully operated in the Venice Lagoon, which removed over 2 tonnes of marine litter during campaigns in 2022 and 2023, functioning in both autonomous and teleoperated modes.
Innovation did not stop at collection. The retrieved litter was classified, analysed and directed into advanced recycling processes—transformed into new polymers, products and materials, ready to re-enter the production cycle. A tangible example of circular economy, demonstrating that even the most challenging waste streams, such as marine plastic litter, can be given a second life.
A multidimensional challenge: science, community, awareness
“Technology is a powerful tool, but it is not enough on its own. Addressing the marine litter problem requires a systemic transformation—cultural even before technical,” explains Isabel Gomes, researcher at CIMA Research Foundation and coordinator of MAELSTROM’s Legacy Document. “That’s why we integrated awareness-raising, community engagement, dialogue with policymakers, and support to public policy development.”
Over its four-year duration, MAELSTROM activated citizen clean-up campaigns in Italy, Spain and Portugal, collaborated with schools and artists, organised public events and technological demonstrations. It was showcased at United Nations negotiations on plastic pollution (UNEP INC), bringing empirical evidence to the forefront of international diplomacy. The project promoted a renewed environmental literacy, grounded in scientific transparency and citizen participation.
The results were tangible: over 4 tonnes of marine litter removed, new patented technologies, a mobile app for coastal litter monitoring, and numerous educational and research activities, including 10 Master’s theses and 2 PhD programmes developed within the project. The impact extended to local communities in the pilot areas of Vila do Conde and Venice, where MAELSTROM helped raise awareness on marine pollution and the value of science-based, participatory solutions.
The project’s legacy: the value of a living document
The Legacy Document, coordinated by CIMA Research Foundation, stands as one of the project’s most significant outputs. Far from being a mere collection of best practices, it is a living document, offering a scientifically rigorous account of the challenges faced, solutions adopted, lessons learned, and actionable recommendations for those planning future interventions against marine litter.
Structured around the project’s key phases—from site selection to technological implementation and the transformation of recovered materials—it provides practical tools for local authorities, researchers, entrepreneurs and policymakers. A legacy designed to support the development of new environmental policies, contribute to the definition of European standards, and strengthen territorial response capabilities.
“We wanted to include the difficulties, because that’s where the most important lessons come from,” adds Isabel Gomes. “The value of the Legacy Document lies in its honesty—it does not conceal challenges, but analyses them, places them in context, and offers solutions. Only in this way can we hope to bring about real change.”
An award-winning project, a model to replicate
MAELSTROM’s value has been recognised internationally. The project received three major awards: the Atlantic Project Award in the category “Healthy Oceans and Resilient Coasts 2023–2024”, the European Robotics Sustainability Leadership Recognition 2024, and the Blue Rivers and Lakes Award for innovation. These accolades highlight not only the technical quality of the developed solutions, but also the consortium’s ability to merge science, social impact, and systemic vision.
The project has also been acknowledged as a best practice in citizen science and community engagement. It will be featured at the upcoming EGU 2025 conference, during the session Empowering Communities: Citizen Science and Engagement in Tackling Plastic Pollution, as an exemplary case of public participation in scientific research and in the fight against plastic pollution.
Although the MAELSTROM project has officially concluded, its legacy continues to generate value—through recycled materials, empowered citizens, and scalable technologies. Fondazione CIMA remains committed to building on this legacy to shape new pathways for innovation and sustainability.