The use of Vertical Flow Constructed Wetlands in Wastewater Treatment

Alternative to conventional (i.e., the commonly used biological plants) wastewater treatment systems are presented which are appropriate for small communities and settlements. These systems are the natural treatment systems. The emphasis here is given on vertical downflow flow constructed wetlands (VF CWs). First, advantages and disadvantages of these systems are presented compared to conventional systems. Applications in treating different types of wastewaters and various pollutants are summarized. Components, treatment processes and performance are also presented. General description of facility compartments, layout and operation is given. Design guidelines on recommended unit areas, organic loading rates and hydraulic loading rates from various EU countries for VF CW systems used in municipal wastewater treatment, and data on the efficiency of such systems are also presented. Maintenance and operation issues are discussed. Finally, investment and operation and maintenance costs are addressed based on data from full-scale facilities.