Evaluation of the Phytoremediation Capacity of a Natural Wetland Adjacent to Fluvial and Vehicular Infrastructure for Domestic Wastewater Treatment: A Case Study in Central Mexico

Untreated domestic wastewater discharged into rivers and streams severely deteriorates water quality and aquatic ecosystems, especially in regions lacking adequate treatment infrastructure. This study aimed to evaluate the effectiveness of phytoremediation of domestic wastewater by the Sector Popular natural wetland (Mexico), located adjacent to fluvial and crossing structures. The evaluation was conducted by comparing contamination levels in the influent and effluent water, based on Mexican Official Standards (NOM-001-SEMARNAT-1996, NOM-003-SEMARNAT-1997, and NOM-001-SEMARNAT-2021), as well as several water quality indicators for irrigation. The wetland reduced concentrations of five-day biochemical oxygen demand by 98%, chemical oxygen demand by 95%, total suspended solids by 96%, total nitrogen by 92%, total phosphorus by 67%, and fecal coliforms by 96%. However, the treated water did not meet reuse standards for public services due to elevated salinity and residual presence of fecal microorganisms. These findings confirm that natural wetlands can significantly improve the quality of domestic wastewater and help mitigate environmental degradation in rivers. This approach represents a feasible and complementary strategy for wastewater treatment in regions with similar hydrological and infrastructure conditions.