Treatment of Municipal Wastewater by prototype-scale Constructed Wetlands

Abstract

Water is essential for all living beings, yet despite its abundance, much of its unusable due to contamination from human activities, limiting the availability of fresh, clean water in This present research work aimed to evaluate the performance of municipal wastewater treatment system comprises sewage collection near Renigunta in Tirupati District. In this work, plant species such as umbrella plant (Cyperus alternifolius), were utilized in constructed wetlands. Two types of wetlands— vertical flow and recirculation systems—were tested. Key water quality indicators like Biochemical Oxygen Demand (BOD), Chemical Oxygen Demand (COD), Total Solids (TS), Total Suspended Solids (TSS), and Total Dissolved Solids (TDS) were measured in the effluent at different Hydraulic Retention Times (HRT).The recirculation-type wetland demonstrated the highest removal efficiency across all wastewater characteristics. At the optimal HRT, BOD was reduced from 250 mg/L to 62 mg/L, COD from 460 mg/L to 100 mg/L, TS from 2600 mg/L to 820 mg/L, TSS from 400 mg/L to 25 mg/L, and TDS from 2200 mg/L to 800 mg/L, all falling within permissible irrigation standards (BOD ≤ 100 mg/L, TSS ≤ 200 mg/L). The results suggest that biodegrading microorganisms played a key role in COD reduction, while the root zone likely acted as a natural filter. These findings support the use of constructed wetlands as a cost-effective solution for treating municipal wastewater