The ability of free water surface constructed wetland system to treat high strength domestic wastewater: A case study for the Mediterranean

This study evaluates a full-scale free water surface flow-constructed wetland (FWS-CW) system that was developed in 2005 to treat high strength wastewater in Garip village near Lake Eğirdir in the Mediterranean (Turkey). This FWS-CW was the one of the first full-scale wastewater treatment systems of this type in Turkey and the Mediterranean, and as such represents an important reference for the application of CW systems in other regions with similar climates. This FWS-CW system consists of two stages, the first one being comprised of a 3-compartment septic system with the second one comprised of the FWS CW. The treatment efficiency of the system was found to be significantly affected by the pollutant loading rates, hydraulic retention time and temperature. Long term monitoring revealed that the system removed approximately 86%, 92%, 56% and 43% of the total suspended solids (TSS), biochemical oxygen demand (BOD), total nitrogen (TN), and total phosphorus (TP) from the high strength domestic wastewater, respectively. Therefore, this type of FWS can be applied as economical, environment-sensitive and very efficient for TSS and BOD for treating high strength domestic wastewaters. Alternative measures for improving TN and TP are discussed.