San Francisco del Oro Wastewater Treatment Plant, Chihuahua, Mexico

San Francisco del Oro is a municipal wastewater treatment plant located in the town of the same name in Chihuahua, Mexico. The plant serves a population of approximately 4,264 residents, reflecting its role in managing domestic wastewater for this small community in northern Mexico. The facility provides secondary treatment, which is the standard biological treatment process that removes organic matter and suspended solids. With a designed capacity of 950.40 cubic meters per day and an actual discharge volume of 691.20 cubic meters per day, the plant operates below its full capacity. Under Mexican regulations (NOM-001-SEMARNAT-1996), secondary treatment is required for discharges into national waters, and this plant complies with that standard. The treated effluent is discharged into local water bodies that ultimately drain into the Rio Conchos basin, a tributary of the Rio Grande (Rio Bravo). This watershed supports agricultural activities and provides water for communities in the region. The plant's operation helps protect downstream water quality in this arid region where water resources are critical for both human use and ecosystem health.

The plant discharges into the Rio Conchos watershed, which flows into the Rio Grande (Rio Bravo) and eventually reaches the Gulf of Mexico. This basin is ecologically important in the Chihuahuan Desert, supporting riparian habitats and migratory birds. The plant's secondary treatment reduces organic pollution, helping maintain water quality in a region where water scarcity and agricultural runoff are key environmental concerns.