Acatitan Wastewater Treatment Plant, El Alpuyequito, Colima, Mexico

The Acatitan wastewater treatment plant is located in El Alpuyequito, within the municipality of Colima, Colima state, Mexico. It serves a small population of 639 residents, reflecting its role as a local facility for a rural or peri-urban community. The plant provides secondary treatment, which is the standard biological process for removing organic matter and suspended solids. With a designed capacity of 129.60 m³/day and an average discharge volume of 60.48 m³/day, the plant operates below its capacity. Under Mexican regulations (NOM-001-SEMARNAT-1996 and subsequent updates), secondary treatment is required for discharges into water bodies, and the plant's performance is subject to federal oversight. The treated effluent is discharged into local watercourses that eventually drain into the Pacific Ocean via the Armería River basin. The region's hydrology supports agricultural activities and local ecosystems, making proper wastewater treatment essential for protecting water quality and downstream habitats.

The plant discharges into the Armería River basin, which flows westward through Colima state to the Pacific Ocean. This watershed supports diverse aquatic life and is important for local agriculture and fisheries. The receiving waters are ecologically sensitive, particularly during dry seasons when dilution capacity is reduced, emphasizing the need for effective secondary treatment to prevent nutrient enrichment and pathogen contamination.