ETE Lençóis Paulista Wastewater Treatment Plant, Lençóis Paulista, São Paulo, Brazil

ETE Lençóis Paulista is a municipal wastewater treatment plant located in Lençóis Paulista, within the state of São Paulo, Brazil. The facility serves an estimated population of 62,551 residents, placing it in the medium-sized agglomeration category for the region. As part of Brazil's expanding sanitation infrastructure, the plant plays a key role in managing wastewater from this inland city. Brazil's wastewater treatment sector is governed by federal laws such as the National Environmental Policy and the National Water Resources Policy, with oversight from state environmental agencies like CETESB in São Paulo. For a plant serving over 50,000 people, secondary treatment is typically expected to meet effluent standards that protect receiving water quality. The plant's operational details, including specific treatment processes, are managed by the local utility. The treated effluent from ETE Lençóis Paulista is discharged into local watercourses that drain into the Tietê River basin, one of the most significant river systems in São Paulo state. The Tietê River flows westward across the state, eventually joining the Paraná River, which empties into the Río de la Plata estuary. This downstream connection underscores the plant's role in safeguarding water quality in a densely populated and economically important watershed.

The plant discharges into tributaries of the Tietê River, which flows through São Paulo state and joins the Paraná River, ultimately reaching the Río de la Plata estuary. The Tietê basin supports diverse aquatic life and is a critical water resource for millions of people. Effective treatment at this plant helps reduce nutrient and pathogen loads, protecting downstream ecosystems and drinking water supplies.