Modified first stage of french vertical flow constructed wetlands for wastewater treatment in highlands: start-up of the system

Abstract

Worldwide, decentralized sanitation systems represent an appropriate, sustainable, simpler, and cost-effective option for communities where conventional wastewater treatment technologies have failed by not considering the inherent characteristics of those societies. In this research, the start-up phase of a cost-effective decentralized sanitation technology is presented: The modified first stage of French vertical flow constructed wetlands for raw wastewater treatment. In the three pilot units comprising the modified first stage, Lolium perenne was the vegetation planted and showed great adaptability to the climatic conditions of the highlands and wastewater characteristics from a combined sewerage. In order to evaluate the performance of the system, in situ parameters were measured and physical chemical analyses were performed from samples of the three units. Efficiencies over 45% were obtained for the removal of organic matter and total suspended solids. The pilots demonstrated that the first stage of French vertical flow constructed wetlands is robust and reliable from their start-up period and treating hydraulic overloads.