ETE Sao Miguel Dois Irmaos - Secondary Wastewater Treatment Plant in Dois Irmaos, Brazil

ETE Sao Miguel Dois Irmaos is a municipal wastewater treatment plant located in the Sao Miguel neighborhood of Dois Irmaos, a city in the state of Rio Grande do Sul, Brazil. The plant serves a population of 4,375 people, placing it in the small agglomeration category under Brazilian wastewater regulations. The plant provides secondary treatment, which is the standard level required by Brazilian environmental legislation (CONAMA resolutions) for most municipal wastewater. Secondary treatment typically involves biological processes to reduce organic matter and suspended solids. The plant discharges an average of 470.40 cubic meters of treated wastewater per day. The treated effluent from ETE Sao Miguel Dois Irmaos is discharged into local water bodies that drain into the Sinos River basin, part of the larger Guaiba River system. This watershed ultimately flows into the Patos Lagoon, one of the largest coastal lagoons in South America. The region's aquatic ecosystems support diverse fish and bird species, and proper wastewater treatment is essential to protect water quality in this ecologically sensitive area.

The plant's discharge enters the Sinos River basin, which flows into the Guaiba River and eventually reaches the Patos Lagoon, a large coastal lagoon connected to the Atlantic Ocean. The Patos Lagoon supports important fisheries and migratory bird populations. Secondary treatment helps reduce nutrient loading and organic pollution, protecting downstream aquatic habitats from eutrophication and oxygen depletion.