Las Nubes Wastewater Treatment Plant, Zacualtipán, Chiapas, Mexico

Las Nubes is a wastewater treatment plant located in the rural community of Las Nubes, within the municipality of Maravilla Tenejapa, Chiapas, Mexico. The plant serves a small population of 456 residents, reflecting its role in a sparsely populated area near the border with Guatemala. As a secondary treatment facility, it provides biological treatment to reduce organic pollutants before discharge. The plant has a designed capacity of 172.80 units and currently treats a daily volume of 43.20 units, indicating it operates well below its maximum capacity. Under Mexican regulations (NOM-001-SEMARNAT-1996 and subsequent updates), secondary treatment is the standard for municipal wastewater to meet discharge quality criteria for receiving water bodies. The plant's operation is part of Mexico's efforts to expand sanitation coverage in rural communities. The treated effluent is discharged into local watercourses that ultimately drain into the Grijalva River basin, one of Mexico's major hydrological systems. The Grijalva River flows through Chiapas and Tabasco before emptying into the Gulf of Mexico. The surrounding region is ecologically significant, supporting diverse aquatic life and providing water for agriculture and communities downstream.

The plant discharges into local streams that are part of the Grijalva River basin, which flows northward through Chiapas and Tabasco to the Gulf of Mexico. This watershed supports important aquatic ecosystems, including wetlands and tropical forests that harbor high biodiversity. The region's heavy rainfall and mountainous terrain make water quality management critical for protecting downstream habitats and community water supplies.