El Quelite Wastewater Treatment Plant, Sinaloa, Mexico

El Quelite wastewater treatment plant is located in the town of El Quelite, within the municipality of Mazatlán, Sinaloa, Mexico. It serves a small population of 456 residents, reflecting its role as a local facility for a rural community. The plant is situated inland, away from coastal areas, and operates under Mexico's national water regulations. The plant provides secondary treatment, which is appropriate for its small scale. It has a designed capacity of 345.60 cubic meters per day, but currently discharges only 43.20 m³/day, indicating low utilization. Mexican wastewater treatment plants are regulated by the National Water Commission (CONAGUA), which sets discharge standards under the Federal Water Rights Law. For small communities, secondary treatment is typically sufficient to meet environmental standards. The treated effluent is likely discharged into a local watercourse that eventually drains into the Pacific Ocean via the region's hydrological network. The surrounding area is part of the Sinaloa coastal plain, supporting agriculture and local ecosystems. Proper treatment helps protect downstream water quality and aquatic life.

The plant's effluent likely enters a local stream or arroyo that flows into the Presidio River or a similar watercourse, eventually reaching the Pacific Ocean near Mazatlán. The region supports diverse aquatic habitats, including estuaries and coastal lagoons, which are important for fish and bird species. Effective secondary treatment reduces organic pollutants and nutrients, safeguarding these downstream environments from eutrophication and contamination.