Subsurface Flow Constructed Wetlands: The Road to Treated Wastewater and Renewed Ecosystems

Growing urbanization and the intensification of agricultural activity have caused an increase in the contamination of water bodies due to the discharge of wastewater with high levels of pollutants. A viable solution to this problem is the implementation of artificial wetlands, which take advantage of natural physical and biogeochemical processes to eliminate these pollutants. These wetlands contribute to removing organic matter and nutrients and provide additional benefits, such as ecosystem services and recreational opportunities (Wu et al., 2023). One particular type of these wetlands are subsurface flow wetlands. In this system, water flows slowly through a permeable substrate, such as gravel or sand, below the soil surface, allowing for greater retention and filtration of pollutants. This increased retention also provides more time for biogeochemical and biological processes to take place, which increases the effectiveness of treatment (Duque-Sarango & Pinos, 2022; Pérez et al., 2024).. In this context, the present study aimed to evaluate the optimal performance of a subsurface flow artificial wetland in the removal of organic matter and nutrients from wastewater. An experimental design was carried out involving the manipulation of different hydraulic retention times, together with the inclusion of the plant species Iris pseudacorus. Thus contributing to the advancement in the field of wastewater treatment and the search for sustainable solutions for water resource management.