Coruche Wastewater Treatment Plant: Advanced Treatment in Santarém, Portugal

The Coruche wastewater treatment plant is located in the town of Coruche, in the Santarém district of Portugal. Serving a population of 5,100, the plant is part of the municipal wastewater infrastructure for this inland community. The facility operates under Portugal's implementation of the EU Urban Waste Water Treatment Directive (91/271/EEC), which sets standards for collection and treatment of wastewater. The plant provides advanced treatment, which goes beyond the secondary treatment required by the EU directive for agglomerations of this size. Advanced treatment typically includes nutrient removal (nitrogen and phosphorus) to protect sensitive receiving waters. The plant has a designed capacity of 7,300 cubic meters per day, with an actual discharge volume of 850.33 cubic meters per day, indicating it operates well below its capacity. 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 westward through Portugal and into the Atlantic Ocean near Lisbon. The advanced treatment helps protect the ecological health of the Tagus River and its downstream estuary, which supports diverse aquatic life and is an important migratory corridor for fish.

The plant discharges into a tributary of the Tagus River, which flows through central Portugal and into the Tagus Estuary near Lisbon before reaching the Atlantic Ocean. The Tagus Estuary is a large, ecologically sensitive area that supports diverse bird populations and serves as a critical stopover for migratory waterfowl. Advanced treatment at Coruche helps reduce nutrient loading to the river, protecting downstream water quality and the estuary's ecological balance.