San Antonio Wastewater Treatment Plant, Colima, Mexico

San Antonio is a municipal wastewater treatment plant located in the town of San Antonio, within the municipality of Minatitlán, Colima, Mexico. The plant serves a small population of 365 residents, reflecting its role in a rural or semi-urban community. It operates under Mexico's national water regulations, which mandate treatment standards for discharges into the environment. The plant provides secondary treatment, a standard biological process that removes organic matter and suspended solids. Its designed capacity is 129.60 cubic meters per day, though current discharge volume is 34.56 cubic meters per day, indicating operational headroom. As a small facility, it is subject to Mexican Official Standards (NOMs) for wastewater discharge, which set limits on pollutants to protect water quality. The treated effluent is discharged into local watercourses that drain toward the Pacific Ocean. The region's hydrology includes rivers flowing from the Sierra Madre del Sur, supporting diverse aquatic habitats. Proper treatment at this plant helps safeguard downstream ecosystems and community water resources in the Colima coastal basin.

The plant's discharge enters local streams that flow toward the Pacific coast of Colima, a region characterized by tropical dry forests and seasonal rainfall. The receiving waters support aquatic life and are part of a watershed that ultimately reaches the ocean. Effective secondary treatment reduces organic load and protects downstream ecological health, including fish and invertebrate communities in coastal lagoons and estuaries.