ETE Vargem Pequena Wastewater Treatment Plant, Rio de Janeiro, Brazil

ETE Vargem Pequena is a wastewater treatment plant located in the Vargem Pequena neighborhood of Rio de Janeiro, Brazil. Serving a population of approximately 9,461, it is part of the municipal wastewater infrastructure for the Rio de Janeiro metropolitan area. The plant is situated in the Região Sudeste, within the state of Rio de Janeiro. Brazil's wastewater treatment facilities are regulated under the National Water Resources Policy (Law 9.433/1997) and the National Environmental Council (CONAMA) resolutions. For plants serving populations under 10,000, secondary treatment is typically required to meet effluent standards. The plant's designed capacity is 1.00 volume unit, indicating its scale relative to the served population. The treated effluent from ETE Vargem Pequena likely discharges into local water bodies that drain into the Atlantic Ocean via the coastal watershed of Rio de Janeiro. The region's coastal ecosystems, including mangroves and lagoons, are sensitive to nutrient loading and require effective treatment to protect water quality and aquatic life.

The plant is located within 50 km of the Atlantic coast, in the coastal watershed of Rio de Janeiro. Treated effluent likely flows into local rivers or streams that drain into Guanabara Bay or the Atlantic Ocean. The downstream environment includes sensitive coastal ecosystems such as mangroves and estuarine habitats, which support diverse aquatic life and are important for regional biodiversity. Effective wastewater treatment is critical to prevent eutrophication and protect these ecosystems.