O Carballino Rio Arenteiro Wastewater Treatment Plant, O Carballiño, Galicia

O Carballino Rio Arenteiro is a wastewater treatment plant located in O Carballiño, Ourense, in the autonomous community of Galicia, Spain. The plant serves a population of about 17,380 people, placing it in the medium agglomeration category under Spanish and EU regulations. As a Spanish facility, the plant operates under the EU Urban Waste Water Treatment Directive (91/271/EEC), which requires secondary treatment for agglomerations of this size. The directive also mandates more advanced treatment if the receiving waters are designated as sensitive areas. The regulatory framework ensures compliance with national and European standards. The treated effluent is discharged into the Arenteiro River, a tributary of the Miño River, which flows into the Atlantic Ocean at the Ría de Vigo. The Miño basin supports diverse aquatic life and is an important ecological corridor in the Iberian Peninsula. The plant's operation helps protect water quality in this river system.

The plant discharges into the Arenteiro River, which flows into the Miño River, one of the major rivers in Galicia. The Miño River ultimately reaches the Atlantic Ocean via the Ría de Vigo, a coastal estuary. The watershed supports diverse aquatic ecosystems, including fish species such as Atlantic salmon and brown trout. Protecting water quality in this basin is important for both ecological health and downstream human uses.