ETE 4 Rio das Antas - Irati, Paraná Wastewater Treatment Plant

ETE 4 Rio das Antas is a municipal wastewater treatment plant located in Irati, Paraná, Brazil. The facility serves an estimated population of 38,233, placing it in the medium-agglomeration category for Brazilian wastewater infrastructure. Its location along BR-277 positions it within the broader sanitation network of the Paraná state. Brazilian wastewater treatment plants of this scale are typically required to meet secondary treatment standards under CONAMA Resolution 430/2011 and state-level environmental regulations. The plant's treatment process and capacity details are not publicly available, but facilities serving populations of this size in Paraná often employ biological treatment systems such as activated sludge or stabilization ponds to comply with effluent quality standards. The plant discharges treated effluent into the local watershed, which ultimately drains into the Iguaçu River basin. The Iguaçu River flows through the Atlantic Forest biome, a globally significant biodiversity hotspot. Downstream, the river feeds the Iguaçu Falls and eventually joins the Paraná River, supporting diverse aquatic ecosystems and providing water resources for communities in the region.

The plant's treated effluent enters the Rio das Antas watershed, a tributary of the Iguaçu River basin. The Iguaçu River flows through the Atlantic Forest, one of the world's most biodiverse ecosystems, and eventually reaches the Iguaçu Falls before joining the Paraná River. The watershed supports sensitive aquatic habitats, including fish migration corridors and riparian forests that require careful management of nutrient and pollutant loads.