ETE GUAREI Wastewater Treatment Plant, Guareí, São Paulo, Brazil

ETE GUAREI is a municipal wastewater treatment plant located in Guareí, a city in the state of São Paulo, Brazil. The plant serves a population of about 6,754 residents, reflecting its role in managing domestic wastewater for a small agglomeration in the southeastern region of the country. The plant provides secondary treatment, which is the standard biological treatment required under Brazilian regulations (CONAMA resolutions) for municipal wastewater. This level of treatment removes organic matter and suspended solids, ensuring that the effluent meets basic quality standards before discharge. The plant handles an average daily flow of 770.15 cubic meters. The treated effluent is discharged into local water bodies that ultimately drain into the Paraná River basin, one of the largest river systems in South America. By treating wastewater to secondary standards, ETE GUAREI helps protect downstream water quality and supports the ecological health of the region's freshwater resources.

The plant's discharge enters local streams that flow into the Paranapanema River, a major tributary of the Paraná River. This basin supports diverse aquatic life and provides water for agriculture and communities downstream. Secondary treatment reduces organic pollution, helping to prevent eutrophication and maintain oxygen levels in receiving waters.