This case study evaluated the physical, chemical, and microbiological impacts of treated wastewater effluent from a macro-sized WWTW (>25 ML/day) on a receiving river. Routine compliance parameters (pH, conductivity, NH₃, PO₄³⁻, NOₓ, and E. coli) were assessed alongside additional pollutants of emerging concern, including heavy metals, volatile and semi-volatile organic compounds (VOCs/SVOCs), and enteric pathogens. Overall, the WWTW demonstrated strong compliance with discharge permit requirements and effective removal of phosphates, NOₓ, and most monitored metals.

However, partial removal of certain metals (Cu, Pb, Hg, Se) and the detection of trichloromethane (a chlorination by-product) in treated effluent and downstream river samples highlight ongoing operational challenges. While enteric pathogens were largely removed during treatment, pollution indicators upstream suggest non-point source impacts on the river system. The findings reinforce the importance of integrated monitoring strategies that address both compliance parameters and emerging micro-pollutants to protect aquatic ecosystems.