In 2023, Australia put a 330-square-metre floating wetland on a wastewater lagoon

Floating wetlands slash wastewater greenhouse gas emissions Installing a floating wetland planted with native vegetation on an Australian municipal wastewater lagoon cut methane emissions by up to 66 per cent, according to the results of a two-year field trial. Published on 25 August 2026 in the Journal of Environmental Management, the peer-reviewed study looked at how constructed floating wetlands affect greenhouse gas emissions from open water storage. The trial was carried out at a Westernport Water treatment facility on Phillip Island, Victoria, by researchers from RMIT University, Australia's national science agency CSIRO, and Westernport Water. The trial measured emissions continuously using "Pondi", a solar-powered sensor system developed by RMIT with partners from Deakin University, The University of Queensland and Leading Edge Engineering Solutions. During the monitoring period, carbon dioxide emissions fell by up to 36 per cent, while nitrous oxide levels dropped by 18 per cent compared with a control lagoon without a floating platform. Wastewater treatment around the world produces about 1.6 per cent of human-caused greenhouse gas emissions. Much of this comes from high ...