LLERA Wastewater Treatment Plant, Llera, Extremadura, Spain

The LLERA wastewater treatment plant is located in Llera, a municipality in the province of Badajoz, Extremadura, Spain. The plant serves a population of approximately 2,500 people, classifying it as a small agglomeration under Spanish and EU regulations. The plant provides secondary treatment, which is the minimum required by the EU Urban Waste Water Treatment Directive (91/271/EEC) for freshwater discharges from agglomerations of this size. The designed capacity is 4,000 cubic meters per day, with an average daily discharge volume of 453.12 cubic meters, indicating ample reserve capacity. The treated effluent is discharged into a local watercourse that ultimately drains into the Guadiana River basin, one of the major river systems in the Iberian Peninsula. The Guadiana River flows southwest through Extremadura and into the Gulf of Cádiz (Atlantic Ocean), supporting diverse aquatic ecosystems and agricultural irrigation along its course.

The plant's discharge enters a tributary of the Guadiana River, which flows through the semi-arid Extremadura region before reaching the Atlantic Ocean. The Guadiana basin supports important habitats for migratory birds and freshwater species, including the endangered Iberian lynx in its riparian zones. The secondary treatment helps reduce organic pollution and protect downstream water quality in this ecologically sensitive river system.