Runa Wastewater Treatment Plant, Torres Vedras, Portugal

Runa wastewater treatment plant is located in the parish of Runa, part of the municipality of Torres Vedras in the Lisbon District of Portugal. The facility serves a population equivalent of 4,900, classifying it as a small to medium agglomeration under Portuguese and EU regulations. The plant operates at the secondary treatment level, 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 designed capacity is 6,333 cubic meters per day, and the current discharge volume is approximately 817 cubic meters per day, indicating ample reserve capacity. The treated effluent is discharged into local watercourses that ultimately drain into the Atlantic Ocean via the Tagus River basin or nearby coastal streams. The plant plays a key role in protecting the region's water quality and supporting the ecological health of downstream environments.

The plant discharges into the Tagus River basin, which flows into the Atlantic Ocean near Lisbon. The downstream environment includes estuarine and coastal habitats that support diverse aquatic life, including migratory fish species. The secondary treatment provided helps reduce organic load and nutrient inputs, mitigating eutrophication risks in the sensitive coastal zone.