Vila Nova da Barquinha Wastewater Treatment Plant, Santarém, Portugal

Vila Nova da Barquinha wastewater treatment plant is located in the town of Vila Nova da Barquinha, in the Santarém district of central Portugal. The plant serves a population of approximately 5,000 residents, making it a small-scale municipal facility. It is situated inland, away from the coast, and its operations are part of the region's water management infrastructure. The plant provides secondary treatment, which is the standard biological treatment required under the EU Urban Waste Water Treatment Directive (91/271/EEC) for agglomerations of this size. The designed capacity is 10,793 m³/day, and the current discharge volume is 833.65 m³/day, indicating that the plant operates well below its capacity. The treatment process involves biological degradation of organic matter, followed by sedimentation to remove solids. The treated effluent is discharged into the local watershed, which ultimately drains into the Tagus River (Rio Tejo), one of the longest rivers in the Iberian Peninsula. The Tagus flows westward through Portugal and empties into the Atlantic Ocean near Lisbon. The plant plays a key role in protecting the Tagus basin from untreated wastewater, supporting aquatic life and downstream water quality.

The plant discharges into the Tagus River basin, which flows through central Portugal and into the Atlantic Ocean near Lisbon. The Tagus is a major ecological corridor, supporting diverse aquatic species and providing water for agriculture and urban use. The plant's secondary treatment helps reduce organic pollution and nutrient loads, protecting the river's ecological health and downstream estuarine habitats.