CIUDAD RODRIGO Wastewater Treatment Plant, Ciudad Rodrigo, Spain

The CIUDAD RODRIGO wastewater treatment plant is located in Ciudad Rodrigo, a municipality in the province of Salamanca, within the autonomous community of Castilla y León, Spain. The plant serves a population of approximately 29,754, classifying it as a medium-sized agglomeration under European Union classification. As a Spanish wastewater facility, the plant operates under the EU Urban Waste Water Treatment Directive (91/271/EEC), which requires secondary treatment for agglomerations with a population equivalent between 10,000 and 150,000. The directive also mandates more advanced treatment if the receiving waters are designated as sensitive areas, such as those prone to eutrophication. The treated effluent from the plant is discharged into the Águeda River, a tributary of the Douro River, which flows westward into Portugal and eventually reaches the Atlantic Ocean near Porto. The Douro basin supports diverse aquatic life and is an important ecological corridor in the Iberian Peninsula.

The plant discharges into the Águeda River, a tributary of the Douro River. The Douro River flows through Spain and Portugal, emptying into the Atlantic Ocean. The watershed supports diverse aquatic ecosystems, including migratory fish species such as the European eel and various cyprinids. The region's Mediterranean-continental climate influences seasonal flow variations, making consistent treatment important for downstream water quality.