Aveiras_Virtudes Wastewater Treatment Plant, Azambuja, Portugal

Aveiras_Virtudes is a wastewater treatment plant located in Aveiras de Baixo, Azambuja, in the Lisbon district of Portugal. The plant serves a population of approximately 4,700 people, placing it in the small agglomeration category under Portuguese and EU regulations. The plant provides secondary treatment, which is the standard required by the EU Urban Waste Water Treatment Directive (91/271/EEC) for freshwater discharges from agglomerations of this size. The plant has a designed capacity of 8,310 cubic meters and treats an average annual volume of 783.63 thousand cubic meters. The treated effluent is discharged into a local watercourse that ultimately drains into the Tagus River basin, one of the major river systems in the Iberian Peninsula. The Tagus River flows west through Portugal to the Atlantic Ocean near Lisbon, supporting diverse aquatic ecosystems and providing water for agriculture and urban use.

The plant discharges into the Tagus River basin, which flows into the Atlantic Ocean at the Tagus Estuary near Lisbon. The estuary is an ecologically sensitive area that supports diverse aquatic life, including migratory fish species and waterbirds. The plant's secondary treatment helps reduce organic pollution and protect downstream water quality.