A Dutch startup led by sailors and surfers has devised an effective way of catching trash in rivers. The Great Bubble Barrier deploys a perforated tube laid diagonally on riverbeds to create a curtain of bubbles which snags plastic particles as small as 1mm and intercepts as much as 86% of flotsam in inland waters, directing it to a catchment system that collects and compresses the waste. The air compressor runs on renewable electricity and operates 24/7, regardless of water levels, and allows aquatic life and river traffic to pass unhindered. The first barrier was installed in Amsterdam in 2019 and a second last summer at Katwijk. “Our Amsterdam system is preventing 8,000 pieces of plastic from reaching the North Sea each month,” says co-founder Francis Zoet. Bubble barriers are now being planned for Portugal and Germany.