Utilizing floating treatment wetlands for canal remediation: A case study from Ho Chi Minh City, Vietnam

The floating treatment wetland (FTW) technology has significant potential for treating canal water. Most studied systems are lab-scale, so it is difficult to evaluate the feasibility of applying FTW systems to real canals or other water bodies. In this study, three FTWs with different configurations including FTW–advanced (with buoyant frames made by bamboo stems and planted on plastic rack units), FTW–PVC (with buoyant frames made by polyvinylchloride pipes and planted on plastic nets), and FTW–bamboo (with buoyant frames made by bamboo stems and planted on plastic nets) were installed in a canal with hydrodynamic flow (Hang Bang–A) and in a static canal (Hang Bang–B). The results indicated that FTW systems achieved a better performance in the Hang Bang–B canal with removal efficiencies of 23 % of organic matter, and 34 % of total nitrogen, compared to 19 % of organic matter, and 17 % of total nitrogen in the Hang Bang–A canal. The Escherichia coli concentration measured in Hang Bang–A canal was 4.6 – 4.9 log CFU 100 mL⁻¹ and around 4.3 log CFU 100 mL⁻¹ in Hang Bang–B canal. The failure to reduce E. coli concentrations during operation demonstrates that the FTW system has a limitation in treating pathogens. Additionally, the FTWs contribute to urban green space and the biodiversity of regional ecosystems.