ETE AVAI Wastewater Treatment Plant, Avaí, São Paulo, Brazil

ETE AVAI is a municipal wastewater treatment plant located in Avaí, within the state of São Paulo, Brazil. The facility serves a population of approximately 2,930 people, classifying it as a small-scale treatment operation in the region. The plant provides secondary treatment, which is the standard biological treatment stage required under Brazilian regulations for communities of this size. Secondary treatment typically involves biological processes to remove organic matter and suspended solids, ensuring effluent meets basic quality standards before discharge. The treated effluent is discharged into local water bodies, contributing to the protection of the Tietê River basin, which ultimately flows into the Paraná River system. This river network is ecologically significant, supporting diverse aquatic life and providing water resources for downstream communities and agriculture.

The plant discharges into local streams that are part of the Tietê River basin, a major tributary of the Paraná River. The Paraná River system is one of South America's largest, supporting extensive biodiversity and providing water for irrigation, industry, and drinking water. Downstream environments include floodplains and wetlands that serve as important habitats for fish and migratory birds.