Constructed wetlands for wastewater treatment in Colombia

A modular wastewater treatment system has been installed for the Colombian Coffee Growers Federation (FEDERACAFE) at the Fundacion Manuel Mejia reside ntial training centre. This system was designed by the University of Portsm outh, UK, and based on previous experience with the Gravel Bed Hydroponic ( GBH) constructed wetland system. The steep topography of the site posed con straints on the design and a modular system composed of a rock filter in ga bions for primary treatment, GBH beds for secondary treatment and a pond fo r tertiary treatment was selected. This system was designed to follow the c ontours of the site and maximise treatment. The GBH reed bed was planted with Typha angustifolia in early 1997. The sys tem is being monitored by CENICAFE, the research division of FEDERACAFE. Mo nitoring of the system has shown large BOD removals from more than 350 to l ess than 20 mg/l. Initial results have also suggested 4 log cycle reduction s in indicator bacteria. It is hoped that the success of this system will result in the replication of the treatment process at many villages in the Colombian coffee growing r egion where conventional sanitation technologies are impractical. (C) 1999 IAWQ Published by Elsevier Science Ltd. All rights reserved.