LILLO Wastewater Treatment Plant, Lillo, Castilla-La Mancha, Spain

The LILLO wastewater treatment plant is located in Lillo, a municipality in the province of Toledo, Castilla-La Mancha, Spain. The plant provides advanced treatment for a population of approximately 3,600 residents, ensuring high-quality effluent before discharge. As an advanced treatment facility, LILLO goes beyond secondary treatment to remove nutrients and other pollutants, meeting stringent standards under Spanish and EU regulations. The plant operates under the EU Urban Waste Water Treatment Directive (91/271/EEC), which requires appropriate treatment for agglomerations of this size to protect sensitive areas. The treated effluent is discharged into local watercourses that ultimately drain into the Tagus River basin, one of the most important river systems in the Iberian Peninsula. The advanced treatment helps safeguard downstream aquatic ecosystems and supports water quality in the region.

The plant discharges into the Tagus River basin, which flows westward through central Spain and Portugal before reaching the Atlantic Ocean near Lisbon. The Tagus supports diverse aquatic life and provides water for agriculture and urban use. Advanced treatment at LILLO reduces nutrient loads, helping to prevent eutrophication in downstream reservoirs and estuaries.