Constructed wetlands for wastewater treatment in the Czech Republic - State of the art

Constructed wetlands are an emerging technology in the Czech Republic. The inventory survey in 1993 revealed that since 1989 about 30 systems have been put into operation. The major reason for the inventory was to identify the main design criteria used in functional systems. It was found that all constructed wetlands are horizontal subsurface flow systems. The treatment area ranges between 20 and 6000 m(2), population equivalent ranges between 4 and 1200. In most systems common reed (Phragmites australis) Is used as a plant cover; other plants used are reed canarygrass (Phalaris arundinacea) and American mannagrass (Glyceria maxima). As filtration media sand, gravel and their mixtures are used. The treatment efficiency is high ill terms of BOD5, COD and suspended solids while removal of phosphorus and nitrogen is lower.