Constructed Wetland: A Green Approach to Handle Wastewater

Abstract

Natural wetlands are able to manage all local contamination by naturally occurring agents such as sunlight, aeration, biotic interaction, microbial action, precipitation, and gravitational attraction. Contaminants are removed from the system through volatilization, sedimentation, infiltration, dilution, and oxidation, among others. Constructed wetlands aim to simulate a natural wetland system through optimal configurations of wetland plant types and density, waste characteristics, flow rate, soil types, and stratification. In this way, wastewater can be effectively treated in a natural way, without heavy machinery and additional chemicals that may increase pollution. This chapter discusses the different types of constructed wetlands, the types of wetland plants, and the transformation mechanisms of major nutrients and metals in wetlands, along with suitability and limitations. Finally, the operational requirements, maintenance, and cost of a wetland system are described.