Rizo de Oro Wastewater Treatment Plant, La Concordia, Chiapas

Rizo de Oro is a wastewater treatment plant located in the El Jobo area of La Concordia, Chiapas, Mexico. It serves a population of 1,132 residents, making it a small-scale facility within the region's municipal infrastructure. The plant is situated near the coast, within 10 kilometers of the Pacific Ocean. The plant operates with secondary treatment, which is the standard level required under Mexican regulations (NOM-001-SEMARNAT-1996) for municipal wastewater before discharge. Its designed capacity is 152.93 cubic meters per day, and it currently treats an average of 107.14 cubic meters per day, indicating operational capacity below design levels. As a small agglomeration, it falls under regulatory oversight that mandates compliance with discharge standards for organic matter and suspended solids. The treated effluent is discharged into local watercourses that eventually drain into the Pacific Ocean. The surrounding region in Chiapas is ecologically diverse, with rivers and coastal ecosystems that support aquatic life and local fisheries. Proper treatment helps protect downstream water quality and marine habitats from nutrient pollution and pathogens.

The plant discharges into the Grijalva River basin, which flows through Chiapas and into the Gulf of Mexico. The downstream environment includes coastal lagoons and mangrove ecosystems that are important for biodiversity and local livelihoods. Effective secondary treatment reduces the risk of eutrophication and protects sensitive aquatic habitats from excessive nutrient loads.