San Pedro Yolox Wastewater Treatment Plant, San Pedro Yólox, Oaxaca, Mexico

The San Pedro Yolox wastewater treatment plant is located in the municipality of San Pedro Yólox, in the state of Oaxaca, Mexico. It serves a small community of approximately 2,738 people, providing essential sanitation services in this mountainous region of southern Mexico. The plant operates with secondary treatment, which is appropriate for its scale. With a designed capacity of 345.60 cubic meters per day and a current discharge volume of 259.20 cubic meters per day, it operates below its capacity. Under Mexican regulations (NOM-001-SEMARNAT-1996), secondary treatment is standard for municipal wastewater to meet discharge standards for organic matter and suspended solids. The treated effluent is discharged into local waterways that ultimately drain into the Gulf of Mexico via the Papaloapan River basin. The surrounding region is ecologically significant, supporting diverse aquatic life and providing water for local communities and agriculture. Proper treatment helps protect downstream water quality and ecosystem health.

The plant discharges into the Papaloapan River basin, which flows through Oaxaca and Veracruz before reaching the Gulf of Mexico. This watershed supports a variety of freshwater species and is important for local fisheries and agriculture. The region's tropical climate and mountainous terrain make water quality management critical for both human use and ecological balance.