VENTAS DE RETAMOSA Wastewater Treatment Plant, Casarrubios del Monte, Spain

The VENTAS DE RETAMOSA wastewater treatment plant is located in the Capellanía area of Casarrubios del Monte, Toledo, within the autonomous community of Castilla-La Mancha, Spain. The facility serves a population of approximately 6,081 people, classifying it as a small to medium agglomeration under Spanish and EU regulations. The plant employs advanced treatment processes, which go beyond the secondary treatment standard required by the EU Urban Waste Water Treatment Directive (91/271/EEC) for inland agglomerations of this size. Advanced treatment typically includes nutrient removal (nitrogen and phosphorus) to protect sensitive receiving waters. The treated effluent is discharged into the local hydrological network, which ultimately drains into the Tagus River basin. The Tagus River is the longest river in the Iberian Peninsula, flowing westward through Spain and Portugal to the Atlantic Ocean near Lisbon. The advanced treatment helps safeguard water quality in this ecologically important basin, which supports diverse aquatic life and provides water for agriculture and urban use.

The plant discharges into the Tagus River basin, a major Iberian watershed that flows into the Atlantic Ocean. The Tagus River supports diverse aquatic ecosystems and is a critical water resource for central Spain and Portugal. Advanced treatment at this plant helps reduce nutrient loading, protecting downstream habitats from eutrophication and maintaining water quality for sensitive species.