El Pilon Wastewater Treatment Plant, Barranca del Oro, Nayarit, Mexico

El Pilon is a municipal wastewater treatment plant located in Barranca del Oro, a locality in the municipality of Amatlán de Cañas, Nayarit, Mexico. The plant serves a small population of 626 residents, reflecting its role in a rural or semi-urban setting. As part of Mexico's wastewater infrastructure, it contributes to local sanitation and environmental protection. The plant provides secondary treatment, which is the standard biological process for removing organic matter and suspended solids. With a designed capacity of 259.20 cubic meters per day and an actual discharge volume of 172.80 cubic meters per day, it operates below its full capacity. Mexican regulations, such as NOM-001-SEMARNAT-1996, set discharge limits for pollutants, and secondary treatment typically meets these standards for municipal wastewater. The treated effluent is discharged into a local watercourse, likely a tributary of the Río Ameca or another nearby river, which eventually flows into the Pacific Ocean. This small plant plays a key role in protecting downstream water quality and aquatic ecosystems in the region.

The plant discharges into a local stream that feeds into the Río Ameca basin, which drains into the Pacific Ocean near the coast of Nayarit. This watershed supports diverse aquatic life and is important for local agriculture and fisheries. The secondary treatment helps reduce organic pollution and nutrient loads, protecting downstream water quality and the ecological health of the river and coastal zone.