ANNOUNCEMENTS
The performance of a horizontal subsurface flow constructed wetland (HSSF-CW) for the treatment of rural wastewater generated by Ibrahimpur-Masahi village in Haridwar district of Uttarakhand was evaluated between January, 2019 and March, 2019. The performance was evaluated against the performance of a natural pond system, Masahi, Uttarakhand. The wetland comprises of two macrophytes – Canna indica and Phragmites karka. BOD removal efficiency of 36.37% in the wetland was observed. Average BOD concentration in Ibrahimpur pond was found to be significantly less than BOD concentration in Masahi pond. Removal efficiencies of ammoniacal nitrogen and orthophosphate were found to be 17.65% and 3.69% respectively. There was an average reduction of total coliforms and E. coli by 97.11% and 99.25% respectively. An increase in concentration of nitrate nitrogen, however, was observed in the outlet of the wetland. Macrophyte cover over the wetland showed consistent growth. This increase was particularly high towards the middle of March, 2019. The treated water of Ibrahimpur pond was found to be suitable for irrigation use in terms of most relevant parameters except for pathogen level and dissolved oxygen concentration. The hydraulic retention time and surface area of the wetland were found to be insufficient for satisfactory treatment performance. Some practical methods to improve the performance of the wetland have been suggested.
Keywords: constructed wetland, phytoremediation, natural treatment system, Canna indica, Phragmites karka
