ETE São José do Barreiro - Secondary Wastewater Treatment Plant in São José do Barreiro, São Paulo

ETE São José do Barreiro is a municipal wastewater treatment plant located in São José do Barreiro, a city in the state of São Paulo, Brazil. The plant serves a population of 2,802 and provides secondary treatment, which is the minimum standard required under Brazilian regulations for communities of this size. The plant discharges an average of 398.49 m³/day of treated effluent. As a secondary treatment facility, the plant uses biological processes to remove organic matter and suspended solids. Secondary treatment typically involves aeration and sedimentation stages. Brazilian environmental legislation, particularly CONAMA Resolution 430/2011, sets effluent quality standards for such plants, requiring compliance with parameters like BOD, COD, and pH. The treated effluent from the plant is discharged into local water bodies that ultimately drain into the Paraíba do Sul River basin, a major river system in southeastern Brazil. The Paraíba do Sul River flows through the states of São Paulo, Rio de Janeiro, and Minas Gerais, eventually reaching the Atlantic Ocean near Campos dos Goytacazes. The river supports diverse aquatic life and provides water for millions of people, making the plant's role in protecting water quality important.

The plant's discharge enters the Paraíba do Sul River basin, which drains into the Atlantic Ocean. The Paraíba do Sul is a vital water source for the region, supporting agriculture, industry, and drinking water supplies. The river's ecosystem includes fish species such as the piabanha and surubim, and its floodplains provide habitat for migratory birds. Proper treatment helps maintain water quality and ecological balance in this important watershed.