AGREDA Wastewater Treatment Plant, Ágreda, Soria, Castilla y León, Spain

The AGREDA wastewater treatment plant is located in Ágreda, a municipality in the province of Soria, within the autonomous community of Castilla y León, Spain. The plant serves a population of around 13,204, classifying it as a medium-sized agglomeration under EU classification. 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 European standards. The treated effluent from the plant is discharged into a local watercourse, which ultimately flows into the Ebro River basin, one of Spain's major river systems. The Ebro River drains into the Mediterranean Sea, supporting diverse aquatic life and providing water for agriculture and communities along its course.

The plant discharges into a tributary of the Ebro River, which flows through northeastern Spain before emptying into the Mediterranean Sea. The Ebro basin supports a variety of ecosystems, including wetlands and riparian forests, and is home to species such as the European eel and the Iberian barbel. The Mediterranean Sea receives the river's outflow, contributing to the nutrient balance in coastal waters.