ETE Ponte Alta Wastewater Treatment Plant, Itapetininga, São Paulo, Brazil

ETE Ponte Alta is a wastewater treatment plant located in Itapetininga, within the state of São Paulo, Brazil. The plant serves a population of around 125,000 residents, placing it in the medium-to-large agglomeration category for Brazilian wastewater infrastructure. The plant operates under Brazil's regulatory framework, which includes CONAMA resolutions and state-level environmental licensing. For agglomerations of this scale, secondary treatment is typically required to meet effluent standards for organic matter and suspended solids. The plant discharges treated wastewater into local water bodies that ultimately drain into the Paranapanema River basin, a major tributary of the Paraná River system. This river network supports diverse aquatic ecosystems and provides water for downstream communities and agriculture.

The treated effluent from ETE Ponte Alta flows into local streams that are part of the Paranapanema River basin, which drains into the Paraná River and eventually reaches the Río de la Plata estuary. This watershed supports important aquatic biodiversity, including migratory fish species, and provides water for irrigation and drinking water supply downstream. The region's subtropical climate with seasonal rainfall influences the dilution capacity of receiving waters.