Field implementation of a floating wetland system in Kranji reservoir

Abstract

The floating wetland system (FWS) has been used for water treatment due to their low maintenance costs, ecological benefits and aesthetic nature. It is being encouraged in tropical countries to improve the quality of reservoir inflows. Furthermore, it is most suitable for water catchments since it is sustainable in areas of high water depths compared to constructed wetlands.

The main objective of this study was to investigate the use of the FWS as treatment units for the removal of nutrients from the baseflow in Kranji catchment. Typha angustifolia, Vetiveria zizanioides and Polygonum barbatum were used to assess the performance of the FWS. The performance of the FWS was monitored based on the nutrient content in the plants, quantified on the basis of the analysis of the plant biomass for Total Nitrogen (TN) and Total Phosphorus (TP). An assessment of the plant nutrient content was studied through regular monitoring of plant growth based on height measurements and nutrient concentration in the plants at different stages of growth. Plant samples analysed for TN and TP were compared with plant height records in order to find the optimal harvesting time.