Performance Evaluation of Pilot-Scale Constructed Wetlands Planted with Canna Glauca for Domestic Wastewater Treatment

Water is one of the most important natural resources required for the survival of all living organisms and the sustainable development of society. The present study aimed to evaluate the performance of a domestic wastewater treatment system using sewage collected near Leela mahal Circle in Tirupati District. The plant species Canna Glauca was used in the constructed wetland systems. Two types of constructed wetlands, namely vertical subsurface flow and recirculating systems, were investigated for wastewater treatment. The treated wastewater was analysed for important water quality parameters, including Biochemical Oxygen Demand (BOD), Chemical Oxygen Demand (COD), Total Solids (TS), Total Suspended Solids (TSS), and Total Dissolved Solids (TDS), at different Hydraulic Retention Times (HRTs). The recirculating constructed wetland showed the highest removal efficiency for the tested wastewater parameters. At the optimum HRT, BOD decreased from 350 mg/L to 90 mg/L, COD from 480 mg/L to 140 mg/L, TS from 2700 mg/L to 550 mg/L, TSS from 400 mg/L to 50 mg/L, and TDS from 2300 mg/L to 500 mg/L. The treated wastewater met the specified irrigation limits for BOD (≤100 mg/L) and TSS (≤200 mg/L). The results indicate that constructed wetlands, particularly the recirculating system, can effectively reduce organic and solid pollutants in domestic wastewater and produce treated water suitable for irrigation purposes.