Alenquer Wastewater Treatment Plant: Serving Alenquer, Portugal

The Alenquer wastewater treatment plant is located in Alenquer, a town in the Lisbon District of Portugal. It serves a population of around 9,000 residents, placing it in the small-to-medium agglomeration category under EU regulations. The plant is situated inland, approximately 50 km from the Atlantic coast, and its operations are part of the region's municipal wastewater infrastructure. As a Portuguese facility, Alenquer operates under the EU Urban Waste Water Treatment Directive 91/271/EEC, which requires secondary treatment for agglomerations with a population equivalent (PE) between 2,000 and 10,000 discharging into freshwater or estuaries. The plant's designed capacity is 1.00 (likely in thousands of cubic meters per day or similar units), indicating it is sized to handle the local wastewater load. Compliance with national and EU standards ensures that treated effluent meets quality requirements before discharge. The plant's treated wastewater is discharged into a local watercourse that eventually flows into the Tagus River basin, one of the major river systems in the Iberian Peninsula. The Tagus River drains into the Atlantic Ocean near Lisbon, supporting diverse aquatic ecosystems and providing water for agriculture and urban use. The Alenquer plant plays a key role in protecting downstream water quality and the ecological health of the Tagus estuary.

The Alenquer plant discharges into a tributary of the Tagus River, which flows into the Tagus estuary and then the Atlantic Ocean. The Tagus estuary is a vital habitat for migratory birds and supports diverse fish populations. The plant's treatment helps reduce nutrient and pollutant loads, safeguarding the ecological balance of this important coastal and marine environment.