Preliminary Performance Assessment of polyculture vertical flow constructed wetland for campus greywater treatment

Constructed wetlands (CW) are recognized as one of the best nature-based, sustainable solutions for wastewater treatment. This study evaluates the effectiveness of polyculture wetlands in treating campus greywater (GW). A pilot-scale CW, measuring 6 x 3 x 0.7 m (L x B x D), was set up on campus, containing three layers of filter media with plant species Chlorophytum Comosum, Codiaeum Variegatum, and Cyperus Laxus. CW was operated at a flow rate of 120 m³/d over 35 days. This study observed removal efficiencies of 97.8% for turbidity, 52.7% for chemical oxygen demand, 41.1% for biological oxygen demand, 41.7% for total coliforms, 38.2% for phosphorus, 36.7% for oil and grease, and 19.4% for total suspended solids The significant reduction in turbidity reflects the filter bed’s efficiency, while organic matter removal demonstrates the biological activity facilitated by the plant- microbe interactions. These results prove that polyculture-based constructed wetlands offer a sustainable, efficient, and scalable wastewater treatment option applicable for campus decentralized applications. It presents a viable method to minimize environmental pollution and encourage water reuse with an eco-friendly, low-maintenance system, in line with institutional sustainability goals.